“THE US NEEDS TO MOVE AT A FAST PACE TO STAY COMPETITIVE.”
NASA officials say that the US needs to invest in nuclear-powered spacecraft if it wants to beat its geopolitical rivalsto Mars.
The officials were testifying at a House Science, Space, and Tech subcommittee hearing on Wednesday, according to United Press International. They urged lawmakers to invest resources into researching and developing nuclear-powered rockets, which could allow humans to reach the Red Planet in just three to four months — half the time it would take for traditional, chemical propelled rockets.
“Our strategic competitors, including China, are indeed aggressively investing in a wide range of space technologies, including nuclear power and propulsion to fulfill their ambitions for sustained human lunar presence, as well as Martian and deep space science missions,” NASA senior adviser for Budget and Finance Bhavya Lal said at the subcommittee meeting, adding that the “United States needs to move at a fast pace to stay competitive and to remain a leader in the global space community.”
This all comes on the heels of China allegedly testing a hypersonic nuclear-capable missile that took US officials by surprise. Though Beijing was quick to deny the claims, some still look at it as a “Sputnik moment“ because US intelligence had seemingly underestimated the country’s progress.
Congress and NASA have stated that they want to get humans to Mars by 2033. However, Dr. Roger Myer, co-chair of the Committee on Space Nuclear Propulsion Technologies at the Academies of Sciences, threw cold water on that goal, saying that human Mars travel is “likely unobtainable by 2033.”
Meanwhile, Chinese officials have set 2033 as their target date to send taikonauts to Mars, Reuters reports. If Lal is to be believed, China is well on track to get there in that timeline if they continue to invest in nuclear propulsion.
NASA and U.S. aerospace experts urged Congress on Wednesday to invest more quickly and heavily in development of nuclear-powered spacecraft Wednesday to stay ahead of such competitors as China.
The space agency believes spacecraft powered by a nuclear thermal rocket reach Mars in just three to four months, which is about half the time required by traditional, liquid propellant rockets.
“Strategic competitors including China are aggressively investing in a wide range of space technologies, including nuclear power and propulsion,” Bhavya Lal, NASA’s senior advisor for budget and finance, said during a congressional committee hearing Wednesday morning.
“The United States needs to move at a fast pace to stay competitive and to remain a leader in the global space community,” Lal said.
The hearing occurred before the U.S. House of Representatives Science Space and Technology Committee. Experts delivered testimony even as reports emerged that China had tested an orbital rocket to deliver potential nuclear weapons at supersonic speeds.
China acknowledged it tested a spacecraft in August, but said it did not contain nuclear weapons.
The committee took no action as it gathered information for upcoming federal budget proposals.
“If the United States is serious about leading in a human mission to Mars, we have no time to lose,” said U.S. Rep. Don Beyer, D-Va., who chairs the committee.
“Congress has prioritized development of nuclear space propulsion over the past several years, directing about $100 million annually for NASA to advance nuclear thermal propulsion capabilities with the goal of conducting a future in-space flight test,” Beyer said.
NASA and the Department of Energy awarded $5 million to three companies in July to produce a nuclear-powered spacecraft reactor design. NASA officials said much more funding is needed, although agency officials didn’t discuss dollar amounts Wednesday.
The key to developing such nuclear engines is to identify or develop materials that can withstand the heat and exposure involved, said Roger M. Myers, who chairs a committee on space nuclear engines for the National Academies of Sciences, Engineering and Medicine.
“The risks associated with [nuclear propulsion] are a fundamental materials challenge that we think is quite likely solvable,” Myers testified during the hearing.
U.S. Rep. Ed Perlmutter, D-Colo., asked if any “fundamental scientific limitations” exist for a crewed Mars trip by 2033, or if it was just a matter of Congress appropriating the needed funds for technology development.
NASA can overcome challenges for a human mission to Mars given the resources, but the propulsion method for such a spacecraft is only one issue NASA much confront, Lal said.
“Deep space transport is just one piece of getting to Mars. … We’ve landed small rovers there but a spacecraft carrying humans would be much bigger,” Lal said. “We also need to make sure that the environmental control and life support systems can keep [astronauts] alive for two to three years.”
A MAN who claims he is a time traveler says he has “photo proof” of what the world will be like in 2118.
Alexander Smith has told how he made frequent trips back and forth in time as part of a “top secret” CIA mission in 1981 – and says he managed to take a snap to prove it.
He claims he took the picture of the futuristic skyline while “visiting” the year 2118, an experience he said he “will never forget”.
Speaking to Apex TV, Alexander explained he was putting his life on the line by revealing details of his so-called voyages to the future.
But that didn’t deter the alleged former CIA agent, who went on to speak at length about global warming and aliens, who are apparently due to drop by earth “in a few decades”.
But at no point during the interview – in which he proudly brandishes his photo – does he explain exactly how he managed to pull off his amazing time travelling feat.
Speaking to YouTube channel Apex TV, Alexander said: “I visited the year 2118 as part of a top secret CIA mission.
“As to my knowledge, it was one of the first times that time travel had successfully been completed.
“I went to the future and then back to the past. This happened in 1981.”
Mr Smith, who claims he is opening himself up to danger by taking the interview, also reveals that when aliens arrive, they will visit the world’s top officials.
BACK TO THE FUTURE? These time travellers say they’ve been to the future… and here’s their ‘proof’
He added: “Aliens do visit us, there are intelligent extra-terrestrials that do come to Earth, this is in the mid 21st century.
“There is actually contact with intelligent extra-terrestrials long before it was revealed to the public.
“These aliens don’t necessarily live among us but they do visit from time to time.”
Alexander also claims to know the world’s greatest risk in the future.
He added: “There are many threats to the human race.
“The number one threat to humanity as we know it is global warming, rising sea levels as well as the increase in Co2 in our atmosphere.”
WORLD WAR III CLAIMS
The self-professed time traveller later shared further details of his so-called expeditions in another interview, where he said most of humanity will be confined to towering cities, like the one in his snap.
He believes a “conflict of interests” between the US and North Korea will spark World War III – but it will see the world become “a better place”.
“Borders began to become meaningless and the people began to have a love and appreciation for life – one which would inspire them not to inflict any type of harm upon their neighbour,” Alexander said.
And he said the rest of us will soon be able to see it for ourselves, as he claimed commercial time travel will be available as soon as 2028.
But he’s not the first alleged time travellers have cause a stir which their claims.
A man claiming to be from the year 2030 PASSED a lie-detector test – and has some alarming predictions about the future.
And we also shared the stories of the “time-travellers” who say they can really prove it.
‘Time Traveller’ Claims He Has ‘Photo Proof’ Of Trip To 2118
A ‘time traveller’ has shared ‘photo proof’ of his trip to the year 2118. Check it out here:
Alexander Smith claims to have been sent to the future back in 1981 as part of a classified CIA experiment.
But perhaps fearful that people wouldn’t believe him, he made sure to get a snap of a city from almost 100 years into the future.
As you can see, the photo offers us a grainy glimpse at some greenish wonky-looking buildings.
So in terms of the photo ‘evidence’, all we’ve really gleaned from Alex’s jaunt is that they still have buildings in the future. Top work, mate.
Also, as far as evidence goes, it’s not really the strongest, is it? He may as well have said he’s been to the moon and just held up a picture of the moon.
Still, regardless of whether we accept this photographic proof, Smithy certainly has a lot to say about the future.
Speaking to paranormal YouTube channel Apex TV, he said: “Aliens do visit us, there are intelligent extra-terrestrials that do come to Earth, this is in the mid 21st century.
“There is actually contact with intelligent extra-terrestrials long before it was revealed to the public.
“These aliens don’t necessarily live among us but they do visit from time to time.”
OK, so we’ve got aliens to look forward to, what else?
He continued: “There are many threats to the human race.
“The number one threat to humanity as we know it is global warming, rising sea levels as well as the increase in CO2 in our atmosphere.”
Yeah yeah, global warming – we know about that now, what else?
He said: “I asked them if there had been any wars between 1981 and this year, 2118, and a human looked at me, and she said, ‘I wouldn’t classify it as a war, it was more a conflict, a conflict of interests between two societies’.”
Ah, well that sounds good too. And oh yeah, the President is a robot, by the way.
Alexander said he was putting himself at risk by speaking out about all of this, but he said he thought it was wrong that time travel technology was being used ‘behind closed doors’.
I dunno mate, the process seems to have messed up your face quite badly, not sure if I really fancy it.
Our species has barely gone past our own planet’s moon, and only one of our probes, Voyager 1, has even left the solar system. Much of what we’ve learned about deep space has been pieced together from falling objects and views from telescopes.
But space is rife with unexplained phenomena that put those two mere optical illusions to shame.
And some of the seven included in this slideshow could hold the key to understanding the universe.
Black holes are the ultimate cosmic quicksand. They’re formed when a giant star collapses, imploding into a tiny area of such intense gravity, even the surrounding light is sucked in.
This means that although we’ve got a sense of how black holes work, we’ve still never actually seen one — they’re invisible to telescopes that pick up electromagnetic radiation, light, or X-rays. We can only guess what they look like on the inside.
The Giant Void
Unlike a black hole, the Giant Void isn’t a hole in space — instead, it’s curiously empty of both matter and dark matter. And also different from a black hole, light can pass through the void, though scientists believe it contains dark energy.
It’s not the only void in space, either, although it is the largest, with an estimated diameter of 1.3 billion light years.
Dark matter is still a mystery, but we’re relying on it to help explain some of the unknowns of our universe — cosmologists believe as much as 27% of the universe is dark matter.
We’re more certain of what dark matter isn’t rather than what it is. It’s not made of black holes (the light warping that they’d cause isn’t present).
In addition to the 27% of the universe that’s believed to be dark matter, a lot more is in the form of dark energy, which makes up about 68% of everything around us (the “normal” matter we all know and love is only 5% of the universe).
And like dark matter, we don’t know much about dark energy, but the current hypothesis is that it’s what’s behind the increasing expansion of the universe (whereas dark matter slows it).
Much of our understanding of dark matter and energy comes from the Cosmic Microwave Background, a snapshot of thermal radiation “soon” (380,000 years) after the Big Bang, when hydrogen atoms were first formed.
The Great Attractor
There’s something really attractive 220 million light years away, and it’s dragging our whole galaxy towards it.
Ever since the Big Bang, the entire universe has been expanding, so it makes sense that our galaxy would be moving. But not in the direction it’s headed.
The cluster pointed out above is a gravitational anomaly known as the Great Attractor, and its brightness is due to its gravitational attraction. Some point to dark matter as the cause of this. And others claim that our own galaxy, the Milky Way, is blocking our view of whatever it is that’s pulling us towards it at 1.4 million mph.
Saturn’s mystery moon, “Peggy”
For a brief moment, Saturn had a tiny, mysterious little moon, named Peggy.
Back in 2013, NASA’s Cassini took this snapshot of Saturn’s rings, and caught a disturbance that astronomers believed was a new, little moon forming. The discovery shed light on how Saturn’s 67 other satellites developed.
Unfortunately, as NASA’s Jet Propulsion Lab pointed out in a press release announcing the satellite, “the object is not expected to grow any larger, and may even be falling apart.” Peggy’s current status is unknown.
“Tabby’s Star,” KIC 8462852
The star KIC 8462852 doesn’t just have a snappy, memorable name, it’s also an unsolved anomaly 1,500 light years away.
There’s something big in the way of KIC 8462852, also known as “Tabby’s Star.” About 20% of the light the star emits is blocked from our vantage point. And it’s probably not a planet — even one as large as Jupiter would only block 1% of a star the size of KIC 8462852.
Some have suggested it’s a Dyson Swarm, a less complete version of a megastructure known as a Dyson Sphere, which surrounds a star and harvests its energy output. We’ll probably get a better idea of what’s going on with the star when NASA launches the James Webb Space Telescope in 2018, but until then, “unknown alien megastructure” sounds like a pretty cool explanation.
A person named “John Titor” started posting on the Internet one day, claiming to be from the future and predicting the end of the world. Then he suddenly disappeared, never to be heard from again.
This is our planet’s bleak future: a second Civil War splinters America into five factions, leaving the new capital based in Omaha. World War III breaks out in 2015, starting with Russia and the U.S. trading nukes and ending with three billion dead. Then, to top it all off, a computer bug delivers where Y2K sputtered, destroying our world as we know it. That is, unless an audacious time traveler successfully traverses the space-time continuum to change the course of future history.
In late 2000, that person signed onto the Internet.
A poster going by the screennames “TimeTravel_0” and “John Titor” on a variety of message boards, beginning with the forum at the Time Travel Institute, claimed he was a soldier sent from 2036, the year the computer virus wiped the world. His mission was to head back to 1975 in order to snatch-and-grab an IBM 5100 computer, which had the necessary equipment to fight the future virus. (His detour to the year 2000 was simply to get a little R&R while visiting his three-year-old self, ignoring every fabric-of-time paradox rule from time-travel stories.) Over the next four months, Titor responded to every question other posters had, describing future events in poetically-phrased ways, always submitted with a general disclaimer that alternate realities do exist, so his reality may not be our own. In between dire urgings to learn first aid and stop eating beef—Mad Cow was a serious threat in his reality—Titor provided a number of technical specs regarding how time travel worked, with overly complex algorithms and grainy, hard-to-make-out photos of his actual machine. (Which, yes, of course, was an automobile: a 1987 Chevy Suburban.) He even showed off his cool futuristic military insignia.
On March 24, 2001, Titor offered his final piece of advice (“Bring a gas can with you when the car dies on the side of the road”), signed off forever, and returned home. He was never heard from again.
TODAY, EVERYTHING POSTED ONLINE GETS A HEALTHY DOSE OF SKEPTICISM. LET’S CALL IT THE POST-SNOPES ERA. WE’VE BEEN CONDITIONED TO SUSPECT EVERYTHING.
IN 2003, TITOR FAN Oliver Williams—some may want to put “fan” in quotation marks, simply because of the numerous unsubstantiated theories that Williams himself is/was Titor—launched JohnTitor.com, which tracks Titor’s predictions and offers a compendium of all of his 151 posts. In 2004, members of George Mason University threw together a multimedia rock opera based on Titor. A summary of the tale at io9.com garnered over 103,000 hits in 2011. And, according to IMDB, a feature-length film about Titor is in the pipeline. What seemingly should have been dismissed as a four-month hoax, the work of some nerd killing time at his boring temp job, somehow turned into a phenomenon.
Since the beginning of the mysterious posts, Art Bell’s popular late-night radio program “Coast to Coast AM,” a nationally-syndicated show that covers pretty much everything that’d fit comfortably into an episode of The X-Files, has been the go-to place for all things Titor. George Noory, who replaced Bell in 2003, has continued carrying the torch, devoting entire episodes to the ongoing mystery, fielding inane questions from callers and somehow answering with a straight face. (Examples: “Is there any way that Titor could be a godsend, sent as an angel, to warn us?” and “Do you think there’s any possibility he was a space alien? I’ll hang up and listen.”) In 2006, a lawyer named Lawrence Haber, who claimed to represent Kay Titor, a woman alleging to be John’s mother, contacted Noory. An interview followed between Noory and Kay—with Haber acting as a phone go-between—and it ended up answering, well, pretty much nothing at all.
After that episode, the show intermittently tracked Titor’s proposed timeline, looking at current events like tea leaves, possible harbingers of a nuclear armageddon. But as the false predictions piled up—while many of Titor’s descriptions are vague enough to be considered “not yet disproved,” he did also claim there would be no Olympic Games after 2004—the search for Titor shifted from “Is this real?” to “Who deceived us?”
IN 2003, THE JOHN Titor Foundation, a for-profit Limited Liability Corporation, self-published John Titor: A Time Traveler’s Tale, which is essentially a bound copy of the message board posts. (Used copies of this are currently going for $130 a pop on Amazon.) The Italian investigative TV show Voyager took up the case in 2008, hiring a private eye to locate the folks behind the LLC, and a search led back to the aforementioned Lawrence Haber, who was listed as the company’s CEO. An investigation by amateur sleuth John Hughston, who also goes by the name “Razimus,” uncovered a mysterious P.O. Box in Celebration, Florida, belonging to the LLC. A group of friends with some downtime between gigs at their production company checked out the P.O. Box themselves but found nothing worthwhile. At some point, JohnTitorFoundation.com was created, offering some kind of nonsensical secret code to digital passersby. And just a week ago, Hughston released another video—this one 40 minutes long—in which he names Haber’s brother, Morey, as his prime suspect by using a side-by-side analysis of phrase-usage, which, to be kind, is not exactly a slam dunk.
(Weirder side note: In 2004, a computer engineer named Marlin Pohlman filed a patent for a time travel machine that “back-engineered” concepts in the Titor posts. This started another round of speculation that Pohlman, himself, was the original Titor poster. Last March, he was arrested for drugging and sexually assaulting four women.)
The search for Titor, then, has become more convoluted than Oliver Stone taking on the 9/11 conspiracy. A new piece of information comes out, a tech-savvy kid with some time to kill sees it, decides to give the puzzle a shot, and on and on it goes, the cycle never reaching an end. The trail burns hot, the trail goes cold, but the trail never disappears. There have been countless blog posts and armchair investigations—a Google search for “John Titor solution” bounces back with 325,000 results—but nothing’s come close to finding a worthwhile solution. An itch in the back of the throat remains, unscratched.
THE TITOR LEGEND PERSISTS BECAUSE NO ONE EVER CLAIMED TO BE BEHIND IT. NOW THAT WE WON’T BE FOOLED, WE NEED AN ANSWER. IT’S THE ZEIGARNIK EFFECT; WHEN SOMETHING’S NOT WRAPPED UP, IT PREOCCUPIES OUR MEMORY.
LAST MONTH, BRIAN DUNNING, a writer and producer specializing on the subject of skepticism, devoted an entire episode of his aptly-named podcast Skeptoid to the John Titor phenomenon, less focused on who it might have been and more about that question: why does something without any merit still have legs as an urban legend?
“Now that the number of unsubstantiated claims on the Internet is somewhat larger than the factorial of the square of all the large numbers ever conceived separated by arrow notation,” said Dunning on his podcast, “it would be a lot harder to achieve John Titor’s celebrity.”
Today, everything posted online gets a healthy dose of skepticism. Let’s call it the Post-Snopes Era. We’ve been conditioned—from everyone having access to Photoshop, to Punk’d and Jackass, to found footage films, to big budget viral marketing campaigns, to emails from faux Nigerian princes offering a portion of their riches if we simply send them our bank account number—to suspect everything. Every video of a cat performing a spectacular feat is met with at least one commenter decrying “FAKE!” The Titor story, from a time when we were all so innocent, a time that was less than 15 years ago, came right before things started to change.
And the Titor legend persists, in part, because no one ever claimed to be behind it. Now that we won’t be fooled, we need an answer. It’s the Zeigarnik effect; when something’s not wrapped up, it preoccupies our memory. Our skepticism needs a party responsible, a grand designer that allows it to make sense. When we find out—think the wizard behind the curtain in Oz, or whoever Jacob was supposed to be in that final season of Lost—the mystery ends. No one has claimed Titor, so the story continues.
There are some obvious connections for conspiracy theorists—the fracturing of governments, underground bunkers—but, for everyone else, there’s this: time travel stories are freaking cool. “This is a superpower that everyone would love to have,” said Dunning. “We all want John Titor to actually be from the future.” Who among us didn’t spend idle moments of our youth wondering about flying cars and hoverboards, or what life was like back in the Old West. In fact, when I asked Hughston, the sleuth blogger, why he was initially drawn to Titor, he said that he’d been “a big fan of time travel since about 1985,” the year Back to the Future was released.
But there’s also a much easier explanation. “The John Titor story is popular,” Dunning said, “simply because that happens to be one of the stories that became popular.” If Titor wasn’t leading conspiracy-minded white dudes in their post-graduate years of boredom and confusion down a rabbit hole of mystery, something else would. It’s Urban Legend Darwinism. Among all of the hoaxes, Internet rumors, ghost stories, and Satanic voices you can hear if you play the vinyl backwards, some have to become popular. Might as well be Titor.
There is one other (distant, remote, nearly scientifically impossible) possibility, though.
“ONE OF THE KEYS to cracking the Titor question,” starts an email by someone who goes by the name Temporal Recon, “is to just allow for the possibility that time travel very well could be true.”
The great thing about time travel: the story cannot be refuted. If events don’t happen as the traveler says, that’s because the traveler changed the timeline. “Many never even get off the ground in their research due to this very limiting view,” T.R. said. “They simply don’t believe that the human race will ever conquer time. ‘Ever’ is a very long time, Rick.”
There’s a particular point-of-view that seems to evolve within every amateur Titor investigator I encountered. As the puzzle fails to be solved, when no serious candidates present themselves, the goal of locating the hoaxster morphs ever so slightly, allowing in the possibility that maybe, just maybe, time travel could be real. “Look, of course John Titor didn’t travel through time,” they’ll say, only to dramatically shift with the addendum, “but let’s say he did.”
If you squint hard enough—and forget about the last four Olympics—things will always begin to resemble what you want to see, especially when reality’s only a minor quibble.
I mean, couldn’t the political differences that continue to separate America into red states and blue states be precursors to the Second Civil War?U.S.–Russian relations have been kind of strange lately, haven’t they?The history of 2015, when Russia and the U.S. nuke each other into oblivion, is still yet to be written!
Then T.R. writes a sentence that haunts me, one that will no doubt tip me over the edge on a course to try to solve the mystery, to locate the poster, or maybe a precocious kid now armed with a learner’s permit who once met his future self. Graphs and charts will mass, blanketing my small studio apartment, where I’ll only need a bare mattress in the corner, a pizza on the way, and a computer with browser tabs parked on obscure pages of note, set to auto-refresh. Friendships and relationships and family will drift into the ether; there are only so many hours in the day. Hands will blister, fingers will ink-stain, eyes will learn to scan for men in black suits, or white coats, or some combination thereof.
What if everything around you, from the distant stars to your very hands, were a hologram?
One of the great mysteries of modern cosmology is how our universe can be so thermally uniform—the vast cosmos is filled with the lingering heat of the Big Bang. Over time, it has cooled to a few degrees above absolute zero, but it can still be seen in the faint glow of microwave radiation, known as the cosmic microwave background. In any direction we look, the temperature of this cosmic background is basically the same, varying by only tiny amounts. But according to the standard “cold dark matter” model of cosmology, there wasn’t enough time for hotter and cooler regions of the early universe to even out. Even today we would expect parts of the cosmic background to be much warmer than others, but that isn’t what we observe.
One solution to this cosmological problem is known as early inflation. If the observable universe was extremely tiny in its earliest moments, it could have reached a uniform temperature very quickly. Afterwards, the theory says, the universe underwent a brief period of rapid expansion, eventually leading to the universe we observe today. We don’t have any direct evidence for early cosmic inflation, but because it would solve several issues in cosmology, it is a widely supported idea.
Recently, a team of astronomers looked at data from the Planck satellite, which gathered the most accurate measurements of the cosmic background thus far. They wanted to compare fluctuations across vast regions of the sky, known as low multipole moments, with the predictions of the standard cosmological model and a model that’s somewhat stranger, a holographic one. What if everything around you, from the distant stars to your very hands, were a hologram? Like Plato’s cave, our world of solid objects and three-dimensional space would simply be a shadow of a two-dimensional reality. On the human scale a holographic universe would be indistinguishable from the reality we expect, but on a cosmic scale there could be subtle differences we might be able to detect.
In the holographic view of cosmology, early inflation is driven by interactions of the quantum field, which would slightly change the appearance of the cosmic microwave background. This is particularly true for low multipole moments, and this difference makes it possible, at least in principle, to prove that the holographic principle is true. In their paper, published in Physical Review Letters, the team report the holographic model fitting the Planck satellite data slightly better than the standard model. The results don’t prove the universe is holographic, but they are consistent with a holographic model.
The idea that our universe might be holographic comes from string theory. Although string theory hasn’t been proven experimentally, its mathematical structure has an elegance and power that makes it appealing as a theoretical model. The holographic principle in string theory is just such an example. In its broadest form, the holographic principle states that anything you can know about a particular volume of space can be learned by looking at the surface enclosing the volume. Just as a hologram can contain a three-dimensional image within a sheet of glass or plastic, the universe could contain its vast volume within a surface.
For example, imagine a road 10 miles long that is “contained” by a start line and a finish line. Suppose the speed limit on this road is 60 miles per hour, and we want to know if a car has been speeding. One way to do this is to watch a car travel the whole length of the road, measuring its speed the whole time. But another way is to simply measure when a car crosses the start line and finish line. At a speed of 60 miles per hour, a car travels a mile a minute, so if the time between start and finish is less than 10 minutes, we know the car was speeding.
If the holographic principle is true, then the universe can be viewed in two different ways: one of space and volume as we intuitively experience it, and one of a “surface” with one less dimension. This holographic duality is mathematically powerful because some laws of physics can be much easier to work with in one view than the other.
The structure of our universe is driven by the constant pull of gravity between stars and galaxies. In the present era, gravity is weak compared to other forces, and is described as a gravitational field in general relativity. In the dual holographic view, gravity is described as a quantum field that can interact strongly with mass. Since it is easier to calculate weak interactions than strong ones, the general relativity approach is more useful. However, in the early moments of cosmic time, when the universe was hot and dense, the gravitational fields of relativity were strong, so quantum fields of the holographic view might be easier to deal with.
The fact that both the standard and holographic models can account for early inflation supports the idea that the holographic principle applies to our universe. Cosmic inflation remains a mystery, but by viewing the universe as a hologram we might just be able to solve it.
Forget even the most outlandish solar schemes—what if your local power plant were a black hole ?
That over-50-year-old theory began with an idea about what happens when you lower a tester into the mouth of a black hole. Physicists at the time thought they’d need an impossible machine to prove their theory, but now, researchers at the University of Glasgow have found a black hole lifehack.
The idea is simple … by quantum and black hole standards, at least. In the mouth of a black hole, the combination of infinite density and strangeness inside the black hole and the rapidly rotating outer ergosphere would make the dangling object travel faster than light in order.
Think of how a needle stays poised on the surface of a spinning vinyl record: the record is spinning rapidly while the needle stands still. In 1969, physicist Roger Penrose developed this theory and hypothesized that the object would have “negative energy.”
So where does power generation come in?
“By dropping the object and splitting it in two so that one half falls into the black hole while the other is recovered, the recoil action would measure a loss of negative energy—effectively, the recovered half would gain energy extracted from the black hole’s rotation,” the University of Glasgow explains in a statement. By playing off the different layers of wildly different mass, force, and more, an observer to this phenomenon could harness the energy deficit.
That observer would have to be advanced beyond anything humans can imagine today, like the makers of a hypothetical Dyson sphere or any other cosmic power structure. For this reason, the theory’s consequences have always been assigned to some alien civilization within the long timescale of the universe.
Two years after Penrose’s theory emerged, the soviet physicist Yakov Zel’dovich suggested a way to test it on Earth, but even his test required something beyond what humans could engineer: a cylinder like the one in the theory, spinning nearly as fast.
Now, researchers have found a way to subvert the conditions of the original test using sound instead of light. The Glasgow team writes:
“This concept, which is a key step towards the understanding that black holes may amplify quantum fluctuations, has not been verified experimentally owing to the challenging experimental requirement that the cylinder rotation rate must be larger than the incoming wave frequency. Here, we demonstrate experimentally that these conditions can be satisfied with acoustic waves.”
Sound waves travel much more slowly than light and occupy a much lower range of frequencies. The scientists cite the Doppler effect, which accounts for how sound distorts as a passing car honks its horn, for example. They positioned a ring of speakers around a rapidly rotating, sound-absorbing foam disc.
“What’s happening is that the frequency of the sound waves is being doppler-shifted to zero as the spin speed increases. When the sound starts back up again, it’s because the waves have been shifted from a positive frequency to a negative frequency,” researcher Marion Cromb explains in the statement. Then the sound began again and registered as 30 percent louder—because the negative frequency waves had stored energy, the way Penrose and Zel’dovich predicted.
The results aren’t just the stuff of science fiction, either.
“These experiments address an outstanding problem in fundamental physics and have implications for future research into the extraction of energy from rotating systems,” the researchers write. “We’re keen to see how we can investigate the effect on different sources such as electromagnetic waves in the near future,” researcher Daniele Faccio adds in the statement.
Black holes born in the big bang could be the dark matter physicists have sought for decades – if they exist. Now there’s an audacious plan to find the scars they would have left as they punched through the moon.
IF YOU hovered above the surface of the moon and studied it up close, you wouldn’t necessarily see anything special. There would be craters, of course, some dusty slopes and a few featureless, ancient volcanic plains. If you were in the right place, you might get a glimpse of Neil Armstrong’s footprints. But if you knew what to look for, you may find something much more extraordinary than all of this. Hiding on the lunar surface could be a scar left behind by a tiny black hole.
We aren’t talking about any old black holes, but remnants from the dawn of the cosmos. Known as primordial black holes, these theoretical beasts are thought to range in size from the width of a single atom to that of our entire solar system. If they exist, they may explain some of our universe’s greatest mysteries, from the origins of supermassive black holes found at the centres of galaxies to the mysterious planet-like mass at the edge of our solar system. They might even account for dark matter – the roughly 85 per cent of the universe’s mass that we are unable to see, but know must be there in some form.
As yet, there is no evidence that these black holes exist. But now, two physicists have come up with an audacious plan to change that. They want to scour the lunar surface in search of craters left behind as these black holes slammed into – and indeed through – the moon. “It sounds a little bit wild,” says Matthew Caplan at Illinois State University. “But you never know until you check.”
Here are some of the strangest asteroids we’ve encountered so far.
Exploring the solar system is a massive feat for humankind. But we are good at it. In fact, we seem to be better equipped and willing to explore what lies beyond Earth’s frontiers than exploring our planet or its oceans. Today, we have better maps of Mars than we have of the ocean floor.
And as we continue exploring the solar system, we encounter strange things.
The more we learn about the solar system, the more we understand that our cosmic neighborhood is full of strange things.
In this article, we take a look at some of the strangest Asteroids that have been found to date.
4 Vesta, the largest Asteroid
4 Vesta is huge. It is considered the largest asteroid discovered to date in the solar system and was first identified on March 29, 1807, by Heinrich Wilhelm Olbers.
Vesta measures 578 km by 458 km. The supermassive asteroid has a magnitude of +5.4 to +8.5.
With a clear sky and some luck, Vesta can be easily observed with binoculars.
4 Vesta is so massive that it contributes an estimated 9% of the asteroid belt mass. Until a few years, the largest asteroid was considered Ceres. However, this cosmic body was reclassified as a dwarf planet, given its size.
216 Kleopatra is one of the strangest-looking asteroids in our solar system.
Shaped like a bong, the asteroid orbits in the central region of our solar system asteroid belt and has a diameter of around 138 kilometers. 216 Kleopatra could be a contact binary.
In 2008, scientists discovered two smaller moons around the asteroid, which were named Alexhelios and Cleoselene.
The odd shape and the existence of its two moons are thought to have been the result of an oblique impact that occurred around 100 million years ago.
This massive space rock is considered the largest Jupiter trojan in the solar system. It has an extremely elongated shape, equivalent in volume to a sphere of approximately 225 to 250 kilometers in diameter.
This asteroid is considered one of the most elongated bodies of its size ever discovered in the solar system, at approximately 403 km in its longest dimension.
Just like 216 Kleopatra, this asteroid has a 12-km-diameter moon named Skamandrios.
Discovered on the 5th of April, 1853 by Annibale de Gasparis of Naples, 24 Themis is one of the largest asteroids in the asteroid belt. It stands out as the first asteroid to have ice on its surface. Observations in 2009 confirmed the existence of massive amounts of ice, as well as organic molecules.
Observations revealed that the surface of the asteroid is completely covered in ice. The ice may be replenished by an ‘unknown’ reservoir located beneath the surface.
Because 24 Themis is located relatively close to the sun (~3.2 AU), the widespread ice on the asteroid’s surface is somewhat puzzling.
‘Oumuamua is surely the strangest asteroids humankind has ever spotted.
Not only is this asteroid from another solar system, but it is also the very first interstellar visitor spotted by mankind.
What makes this asteroid even more puzzling is that for the last 12 months, there has been great speculation about the asteroid’s true origin.
In fact, the head of Astronomy at Harvard has even theorized that ‘Oumuamua may actually be, not an asteroid, but an alien spacecraft sent to our solar system by an advanced alien species.
This is perhaps the stranges looking asteroid of them all, and it has been dubbed the ‘Skull-Shaped Asteroid.’
Approximately 650 meters (2,000 feet) in diameter, the asteroid often passes relatively close to Earth. The asteroid was first observed on 10 October 2015 by Pan-STARRS. Astronomers argue that given its high orbital inclination and eccentricity, 2015 TB145 may actually be an extinct comet that has shed its volatiles after numerous passes around the Sun.
During the course of its mission, Lucy will fly by seven Jupiter Trojans. This time-lapsed animation shows the movements of the inner planets (Mercury, brown; Venus, white; Earth, blue; Mars, red), Jupiter (orange), and the two Trojan swarms (green) during the course of the Lucy mission.Credits: Astronomical Institute of CAS/Petr Scheirich (used with permission)More animations
Time capsules from the birth of our Solar System more than 4 billion years ago, the swarms of Trojan asteroids associated with Jupiter are thought to be remnants of the primordial material that formed the outer planets. The Trojans orbit the Sun in two loose groups, with one group leading ahead of Jupiter in its path, the other trailing behind. Clustered around the two Lagrange points equidistant from the Sun and Jupiter, the Trojans are stabilized by the Sun and its largest planet in a gravitational balancing act. These primitive bodies hold vital clues to deciphering the history of the solar system.
Lucy will be the first space mission to study the Trojans. The mission takes its name from the fossilized human ancestor (called “Lucy” by her discoverers) whose skeleton provided unique insight into humanity’s evolution. Likewise, the Lucy mission will revolutionize our knowledge of planetary origins and the formation of the solar system.
Lucy will launch in October 2021 and, with boosts from Earth’s gravity, will complete a 12-year journey to eight different asteroids — a Main Belt asteroid and seven Trojans, four of which are members of “two-for-the-price-of-one” binary systems. Lucy’s complex path will take it to both clusters of Trojans and give us our first close-up view of all three major types of bodies in the swarms (so-called C-, P- and D-types).
The dark-red P- and D-type Trojans resemble those found in the Kuiper Belt of icy bodies that extends beyond the orbit of Neptune. The C-types are found mostly in the outer parts of the Main Belt of asteroids, between Mars and Jupiter. All of the Trojans are thought to be abundant in dark carbon compounds. Below an insulating blanket of dust, they are probably rich in water and other volatile substances.
No other space mission in history has been launched to as many different destinations in independent orbits around our sun. Lucy will show us, for the first time, the diversity of the primordial bodies that built the planets.
This diagram illustrates Lucy’s orbital path. The spacecraft’s path (green) is shown in a frame of reference where Jupiter remains stationary, giving the trajectory its pretzel-like shape. After launch in October 2021, Lucy has two close Earth flybys before encountering its Trojan targets. In the L4 cloud Lucy will fly by (3548) Eurybates (white) and its satellite, (15094) Polymele (pink), (11351) Leucus (red), and (21900) Orus (red) from 2027-2028. After diving past Earth again Lucy will visit the L5 cloud and encounter the (617) Patroclus-Menoetius binary (pink) in 2033. As a bonus, in 2025 on the way to the L4, Lucy flies by a small Main Belt asteroid, (52246) Donaldjohanson (white), named for the discoverer of the Lucy fossil. After flying by the Patroclus-Menoetius binary in 2033, Lucy will continue cycling between the two Trojan clouds every six years.Credits: Southwest Research Institute
Source of the signals are unknown and do not correspond to any known natural phenomena
Strange radio signals are coming from the direction of the centre of the galaxy and we aren’t sure what is emitting them. They turn on and off seemingly at random, and their source must be unlike anything else we have seen before.
The source of this radiation has been nicknamed “Andy’s object” after Ziteng Wang at the University of Sydney in Australia, who goes by the name Andy and first discovered the radio waves. He and his colleagues spotted the emissions six times in 2020 using the Australian Square Kilometre Array Pathfinder radio telescope. They made further observations with the MeerKAT radio telescope in South Africa.
The researchers found that the object occasionally flared for up to a few weeks, but was dark most of the time. When it finally lit up again in February this year, several months after the initial detection, they pointed some of the most powerful non-radio telescopes we have at it and saw nothing. “We’ve looked at every other wavelength we can, all the way from the infrared to optical to X-rays, and we see nothing, so it doesn’t seem to be consistent with any kind of star that we understand,” says David Kaplan at the University of Wisconsin-Milwaukee, who was part of the research team.
The fact that it wasn’t visible in any other wavelengths ruled out several possible explanations for this object, including normal stars and magnetars, which are neutron stars with powerful magnetic fields.
Whatever Andy’s object is, the polarisation of the radio waves coming from it indicates that it probably has a strong magnetic field. During flares, its brightness varied by up to a factor of 100, and those flares faded extraordinarily quickly – as fast as a single day – facts that suggest the object is small.
But no astronomical body we know of fits all of those strange traits. “It’s an interesting object that has confounded any attempt we have to explain it,” says Kaplan. “It could turn out to be part of a known class of objects, just a weird example, but that’ll push the boundaries of how we think those classes behave.”
Thats right, NASA is going to take a close look at the $10,000 Quintillion Space Rock!
NASA is planning a mission up to an asteroid that is hurtling around in our solar system, and it could be a seriously lucrative mission if it is a success.
In fact, the number in terms of the potential value of the precious metals that the asteroid may be composed of is simply baffling, because it’s supposedly worth more than $10,000 quintillion.
That’s not even worth doing the UK conversion for, as it’s such an unfamiliar and massive number.
OK, if we must, it’s around £8,072 quadrillion. Does that help at all?
To put that into context, it’s got 22 zeros after it. Written down, it looks like this – 10,000,000,000,000,000,000,000.
It’s worth enough to make everyone currently living on earth a billionaire. That’s a lot of money.
Anyway, the asteroid with this unfathomable wealth of precious metals stashed away on it is called Psyche 16, and it was actually discovered back in March 1852.
The 124-mile space rock is set to become the primary focus of a NASA mission which is set for lift off in August 2022.
If it does go ahead, the craft would arrive on the asteroid about four years later, because – you know – everything in space is a long way away.
This would be the first mission that humans have sent to somewhere that is made out of metal, rather than rock and ice, as NASA said: “Unlike most other asteroids that are rocky or icy bodies, scientists think the M-type (metallic) asteroid 16 Psyche is comprised mostly of metallic iron and nickel similar to Earth.”
It turns out that those sorts of metals in that quantity are worth a hell of a lot
Of course, there is the question of how you would extract that worth, given that it’s floating around in space some four years travel away, but that’s something that NASA will presumably intend to scope out on this prospective mission.
So, the asteroid sits between Mars and Jupiter and is thought to have been the ‘remnants of a protoplanet’ that was destroyed in hit-and-run collisions when the solar system formed’, according to the Daily Mail.
Researchers on a recent study said: “The findings are a step toward resolving the mystery of the origin of this unusual object, which has been thought by some to be a chunk of the core of an ill-fated protoplanet”.
Katherine de Kleer, assistant professor of planetary science and astronomy at Caltech, added: “We think that fragments of the cores, mantles, and crusts of these objects remain today in the form of asteroids.
“If that’s true, it gives us our only real opportunity to directly study the cores of planet-like objects.”
Also, it might be worth an unimaginable amount of money, so it’s probably worth taking a closer look.
TIME is not real – it is a human construct to help us differentiate between now and our perception of the past, an equally astonishing and baffling theory states.
Physicist Max Tegmark claims flow of time is a illusion
The concept of time is simply an illusion made up of human memories, everything that has ever been and ever will be is happening right now. That is the theory according to a group of esteemed scientists who aim to solve one of the universe’s mysteries.
Most people do not even consider the concept of time but there is nothing in the laws of physics to state that it should move in the forward direction that we know.
The laws of physics are symmetric, ultimately meaning time could have easily moved in a backward direction as it does forward.
Indeed some adherents to the “Big Crunch” theory say time will run backwards when the universe stops expanding and starts contracting back in on itself.
This conundrum as to why we interpret time in a forward motion has led scientists to question why.
Time is an illusion (Image: GETTY)
Past, present and future are all ‘now’ (Image: GETTY)
Inevitably, some have concluded that time is simply a human construct.
They argue that there is a ‘block universe where time and space are connected, otherwise known as spacetime.
The theory, which is backed up by Albert Einstein’s theory of relativity, states space and time are part of a four-dimensional structure where everything thing that has happened has its own coordinates in spacetime.
This would allow everything to be ‘real’ in the sense that the past, and even the future, are still there in spacetime – making everything equally important as the present.
Time is formed by memories, according to physicists (Image: GETTY)
Massachusetts Institute of Technology physicist Max Tegmark, told space.com: “We can portray our reality as either a three-dimensional place where stuff happens over time, or as a four-dimensional place where nothing happens [‘block universe’] — and if it really is the second picture, then change really is an illusion, because there’s nothing that’s changing; it’s all just there — past, present, future.
“We have the illusion, at any given moment, that the past already happened and the future doesn’t yet exist, and that things are changing.
“But all I’m ever aware of is my brain state right now. The only reason I feel like I have a past is that my brain contains memories.”
Time is a human concept (Image: GETTY)
Julian Barbour, a British physicist who has authored several books on the subject of time, describes everything as a series of “nows”.
Dr Barbour told physicist and author Adam Frank in the book ‘About Time: Cosmology and Culture at the Twilight of the Big Bang’: “As we live, we seem to move through a succession of Nows, and the question is, what are they?”
He explains, adding to the spacetime theory where everything has its own place: “You can think of it as a landscape or country. Each point in this country is a Now and I call the country Platonia, because it is timeless and created by perfect mathematical rules.”
He adds that what we perceive as the past is simply an illusion formed in our brain.
Dr Barbour: “The only evidence you have of last week is your memory. But memory comes from a stable structure of neurons in your brain now.
“The only evidence we have of the Earth’s past is rocks and fossils. But these are just stable structures in the form of an arrangement of minerals we examine in the present.
“The point is, all we have are these records and you only have them in this Now.”
Zero emissions and a million pounds of lift renew the appeal of these century-old giants.
Tom Grundy, the CEO of Hybrid Air Vehicles, started his career working on fighters and drones for BAE Systems, and he was a project engineering manager for Airbus during the development of the A380. But these days his focus is on a type of aircraft that can do things the fixed-wing fliers he has spent his life admiring can’t—even though the basic technology keeping them aloft is substantially older. Welcome to the second age of the airship.
Grundy’s company is promoting its striking, pillow-like AirLander 10, initially designed for military surveillance, as a pleasant, low-emission alternative means of regional air travel. In May the company announced plans to begin service for up to 100 passengers per flight on a handful of short-haul routes (Liverpool to Belfast, Oslo to Stockholm, Seattle to Vancouver, among others) in 2025. A Scandinavian company is in talks about using the AirLander to give tours of the North Pole.
The chief market for the airships of the 21st century, however, will not be passenger service but freight hauling. The new airships can carry heavier loads farther and cheaper than helicopters can, with lower emissions than fixed-wing aircraft—potentially zero emissions, if the ships are powered by hydrogen fuel cells.
Historically, there have been two major types of airship. Rigid airships, as the name implies, are built around a hard skeleton. Count Ferdinand von Zeppelin of Germany flew the first rigid airships, and on his account, they are sometimes called Zeppelins. The other type of airship is non-rigid. Non-rigid airships have no skeleton. They consist of an envelope inflated with a lifting gas such as helium, from which is suspended a gondola for crew, passengers, and cargo. The familiar Goodyear blimps have been mostly non-rigid airships.
The engineers at Hybrid Air Vehicles looked at the history of rigid and non-rigid airships and came down solidly on the non-rigid side—with a twist. Rather than the cigar or American football shapes of past airships and blimps, the AirLander looks more like a pillow. A radically different design, it’s a lifting body—and heavier than air. It relies on both aerostatic lift from helium and aerodynamic lift to fly, making it a hybrid airship. “About 40 percent of our lift is aerodynamic,” Grundy says. “When we turn our engines off and we slow down, we’re heavier than air. We come down and land just like airplanes do.”
The appealing energy efficiency of airships comes from their ability to float in the air as boats do on water—so it seems strange to purposefully erode that lighter-than-air quality. But there is another, problematic side to aerostatic buoyancy. “If you are taking 50 tons of cargo to a remote part of the world,” Grundy says, “and you want to put that 50 tons down in [that same spot], you now have 50 tons of buoyancy you have to deal with.” Like a pool float held underwater, it’s going to surge upward once you let off the pressure. Airships of yore would manage by venting lifting gas (not something you want to do with limited and expensive helium), taking on ballast, and elaborate rope and mooring procedures. That’s a nonstarter if you want to make money taking big things to places with little infrastructure, Grundy says, but he believes the AirLander is the answer.
When the AirLander had its first flight in Lakehurst, New Jersey in 2012, it was intended as a U.S. Army surveillance craft. The Army canceled that program the following year, and HAV brought the ship across the Atlantic to Cardington, about 60 miles north of London, for a 2016 series of flights that would test its viability for civilian use. In November 2017, the unoccupied AirLander broke free from its mooring mast and deflated. Grundy says the lessons of this incident resulted in improvements to the production model, which remains on schedule. “Our base business plan sees us delivering 12 aircraft per year” beginning as soon as 2025, he says.
The Graf Zeppelin was 776 feet long. Even non-rigid airships could be enormous, according to Wichita State University professor of aerospace engineering Brandon Buerge. He cites the U.S. Navy’s N-Class blimps of the 1950s, tasked with anti-submarine and early-warning missions. They could be as large as 400 feet long and 120 feet tall, “bigger than anything we’ve been flying with any regularity,” Buerge says.
Early on, the German Zeppelins racked up an impressive record for safety and capability. The Graf Zeppelin flew more than a million miles beginning in 1928, circumnavigated the globe, and lifted more than 43 tons. “How long did it take before fixed-wing aircraft caught up?” Buerge asks. (About 30 years. The C-133 Cargomaster—first heavy lifter in the U.S. Air Force—entered service in 1958 and could carry more than 55 tons, but it had four jet fuel-guzzling turboprops.)https://983bce8ec369f0c85acec01a50fdde4a.safeframe.googlesyndication.com/safeframe/1-0-38/html/container.html
Still the rigid giants eventually proved fragile. The German airships used flammable hydrogen for lift, which led to the Hindenburg disaster. And the U.S. Navy’s rigid airships displayed an alarming tendency to break up in bad weather. The Germans scrapped the Graf Zeppelin at the start of World War II, while the American Navy stuck with non-rigid blimps, using them to escort shipping convoys. The blimps proved much more resilient, with one N-Class blimp, the Snowbird, crossing the Atlantic twice and beating the Graf Zeppelin’s record for endurance by flying for more than 264 hours through all kinds of weather.
“Those are the ships they would plow through ice storms,” Buerge says. “It’s hard to kill a non-rigid airship.”
As you approach Moffett Federal Air Field in Sunnyvale, California, Hangars Two and Three are easily visible from U.S. 101, their parabolic apexes and massive door frames hulking over the relatively flat desert landscape. Seeing them from a distance does not prepare you for the feeling of their immensity as you stand between them. The giant hangars channel the early summer breeze like a box canyon. In the 1930s, they housed U.S. Navy airships like the Macon, a behemoth 785 feet long and 150 feet high. More recent tenants include the California Air National Guard and NASA.
The current occupant of Hangar Two, LTA Research, is using it to house airships again. My tour guides on this bright June morning are LTA CEO Alan Weston and LTA chief of operations James McCormick, who acts as a sort of ground wire for Weston’s seemingly boundless energy. Inside the hangar, a chorus of birdsong echoes down from the rafters far overhead.
Before us stands the naked, cigar-shaped skeleton of the airship they have dubbed Pathfinder 1, a 400-foot-long vessel that could easily swallow the fuselage of the Boeing 737 that brought me to California. It’s more organic sculpture than airframe, a latticework of black carbon-fiber tubes rising like the bones of an ancient leviathan awaiting its taxidermied skin—in this case, high-tech sailcloth.
“Isn’t that cool?” Weston asks.
His excitement is catching, but he is in some ways a strange ambassador for the return of a technology that for most of the last 70 years has been more prevalent in science fiction than in the real world, those floating billboards hovering over football stadiums notwithstanding. “Most of my career has been in spacecraft and rockets,” Weston says. He designed kill vehicles for President Ronald Reagan’s Star Wars program and spent 23 years doing research and development for the U.S. Air Force. Then he served as director of programs at NASA Ames Research Center until his retirement in August 2013.
Retirement did not last long. Late that same year, Google co-founder Sergey Brin asked Weston to create a company to build an airship that could carry cargo on his humanitarian relief missions.
Weston’s enthusiasm for his new project grew as he studied the history of airships. The Hindenburg disaster of 1937 might have been the death of airships in the popular imagination, but there have been fresh design efforts in every decade since. (John McPhee’s book The Deltoid Pumpkin Seed documents a push by a strange coalition of former Navy airship men and Presbyterian ministers to develop a hybrid airplane/rigid airship in the 1970s. Their ship flew, but no one wanted it. Their dreams of at once revolutionizing air freight and missionary work went unfulfilled.)
His history lessons complete, Weston concluded that the challenges that plagued the older rigid airships could be overcome. They would use non-flammable helium as a lifting gas, for starters. And the flaws that brought down Navy airships like Akron and Macon—a faulty altimeter and structural damage, respectively—could be corrected with modern avionics and strong, light materials. Each of the 13 rib-like carbon fiber “mainframes” that make up the length of Pathfinder 1 weighs just 600 pounds, but together, they support a vessel with 28 tons of lift. A broken carbon tube can be replaced in-flight.
“The beautiful thing about a rigid airship is you can almost do anything you want,” Weston says. “The problem with all these blimps is you don’t have any hard points.”
Pathfinder 1 will support a gondola, diesel generators, solar panels, batteries, electric motors, and vectored thrust propellers, as well as a small gangway running the length of the envelope for accessing the interior frame. While LTA will not disclose the dimensions of its in-development Pathfinder 3, it will be substantially more capacious than Pathfinder 1, with room enough in the crew gangway for passengers and for hydrogen—for fuel cells, rather than for lift.
Beyond Pathfinder 3, LTA aims to build a massive rigid airship that will dwarf the Zeppelins of the past. All LTA will say on the record about its next-gen giant is that it will be too big to be built in Sunnyvale—LTA is in the process of moving into the former Goodyear Airdock hangar in Akron, Ohio. “The AirDock goes on top of this,” Weston says, gesturing up toward Hangar Two’s distant ceiling. “This is 160 feet tall. The AirDock is 200 feet tall.”
That ship isn’t scheduled to fly until 2023 at the earliest, and Weston and his team have plenty to keep them busy in the meantime, like fully outfitting Pathfinder 1 and flying it to its new home in Akron—following a series of flight tests around the San Francisco Bay area.
Though Weston hopes to begin these short-distance “camping trips” this year, they are currently unscheduled. “History is full of airship projects that crashed or something bad happened because people were in a rush,” Weston says. “We’re going to be careful.”
The Curse of Buoyancy
Igor Pasternak shares Tom Grundy’s view that buoyancy control is key to building a commercially practical airship. The founder of Worldwide Aeros Corporation in Montebello, California, Pasternak built tethered balloons called aerostats as a teenager growing up in Ukraine. Airships, he says, are “what I have been doing all my life.”
He thinks, though, that relying on aerodynamic lift and vectored thrust will limit an airship’s operational capacity. Requiring a runway, even a short one, is another limitation. The vehicle under construction at Worldwide Aeros, the Aeroscraft Dragon Dream, is a non-cylindrical rigid airship. It takes a different approach than Hybrid’s AirLander, using a low-pressure system to compress and release helium to modulate the lift of the airship—compress the helium, shrink its volume, and you reduce aerostatic lift. Prove a heavy-lifting airship can perform true vertical take-offs and landings without ground infrastructure, Pasternak says, and “we are talking about a huge shift, dramatic shift” in the transport business.
That proof is yet to come. The design review for the Dragon Dream operational demonstrator was completed only last summer, and he won’t say when its next test flight will be. As with LTA, he’s pushing the humanitarian applications of airships, having entered into a partnership with the World Food Program that he hopes will eventually see his invention delivering food to famine-struck regions.
The emphasis on charity might help to cover up some observers’ skepticism. “Hope springs eternal” is what aviation analyst Richard Aboulafia says when I ask him if the new airship ventures will change the market. “Frankly, it doesn’t scale,” he explains. “Air travel is all about scale, getting 300 people into a 777. You just can’t do that with these things.”
He can’t readily think of a cargo someone would need to send faster—and at a higher price—than by ship, but slower than by jet. And exotic cargo flown to remote locales is often a one-way trip. “Air cargo is all about equipment utilization, with UPS and FedEx being the best examples of that,” he says. “They have these elaborately choreographed route networks that are all about efficient use of equipment and not having too many one-way trips.”
LTA, Weston admits, is in a privileged position. With a nonprofit humanitarian mission and the backing of some of the world’s wealthiest people, Weston has been freed to think about the challenges of lighter-than-air flight one step at a time. He wants to build airships with no carbon footprint, and so hopes to utilize hydrogen fuel cells in Pathfinder 3 and beyond. Combine oxygen from the air and on-board hydrogen in a fuel cell and you can generate power as well as water, both for consumption and for ballast. “You’re generating the stuff you’re going to drink and use to wash your hands and take a shower with as you are flying around,” Weston says. “We actually gain weight with the water. One kilogram of hydrogen generates nine kilograms of water, so we have plenty of buoyancy control.”
He muses that the success of airships in humanitarian relief could spur the market more generally. Perhaps low-cost, hydrogen-powered cargo airships could spur other industries, such as shipping, to transition to hydrogen power. “I view this as the project of a lifetime,” Weston says. “There’s more opportunity, in my head, to do something useful than anything I’ve ever seen.”
To Buerge the aerospace engineer, helicopters seem like a reasonable analogy to the new airships. “I don’t ride on a helicopter with any regularity, and you probably don’t either,” he says. But even though the civilian helicopter market isn’t near the size of the commercial aircraft industry, “I wouldn’t call helicopters an unsuccessful technology, or a technology that doesn’t exist in a serious way.”
And there’s one element of airships that hasn’t been tested seriously in recent memory: the experience of flying in one.
Buerge once flew in two blimps, a Polar 400 and a Skyship 600, on one of those warm summer days that generate puffy clouds and bumpy rides in fixed-wing aircraft. The dynamics were more like a boat than an airplane, the bow coming up gradually, the ship gliding over a thermal, and then down again. Smooth. “The response isn’t anything that someone that is used to flying in heavier-than-air vehicles would interpret as turbulence,” he says. “It was as close to a magic carpet as I have ever experienced.”
A 900-year-old cosmic mystery surrounding Chinese supernova of 1181AD Solved
A 900-year-old cosmic mystery surrounding the origins of a famous supernova first spotted over China in 1181AD has finally been solved, according to an international team of astronomers. New research says that a faint, fast expanding cloud (or nebula), called Pa30, surrounding one of the hottest stars in the Milky Way, known as Parker’s Star, fits the profile, location and age of the historic supernova.
A 900-year-old cosmic mystery surrounding the origins of a famous supernova first spotted over China in 1181AD has finally been solved, according to an international team of astronomers.
New research published today (September 15, 2021) says that a faint, fast expanding cloud (or nebula), called Pa30, surrounding one of the hottest stars in the Milky Way, known as Parker’s Star, fits the profile, location and age of the historic supernova.
There have only been five bright supernovae in the Milky Way in the last millennium (starting in 1006). Of these, the Chinese supernova, which is also known as the ‘Chinese Guest Star’ of 1181AD has remained a mystery. It was originally seen and documented by Chinese and Japanese astronomers in the 12th century who said it was as bright as the planet Saturn and remained visible for six months. They also recorded an approximate location in the sky of the sighting, but no confirmed remnant of the explosion has even been identified by modern astronomers. The other four supernovae are all now well known to modern day science and include the famous Crab nebula.
The source of this 12th century explosion remained a mystery until this latest discovery made by a team of international astronomers from Hong Kong, the UK, Spain, Hungary and France, including Professor Albert Zijlstra from The University of Manchester. In the new paper, the astronomers found that the Pa 30 nebula is expanding at an extreme velocity of more than 1,100 km per second (at this speed, traveling from the Earth to the Moon would take only 5 minutes). They use this velocity to derive an age at around 1,000 years, which would coincide with the events of 1181AD.
Prof Zijlstra (Professor in Astrophysics at the University of Manchester) explains: “The historical reports place the guest star between two Chinese constellations, Chuanshe and Huagai. Parker’s Star fits the position well. That means both the age and location fit with the events of 1181.”
Pa 30 and Parker’s Star have previously been proposed as the result of a merger of two White Dwarfs. Such events are thought to lead to a rare and relatively faint type of supernova, called a ‘Type Iax supernova’.
Prof Zijlstra added: “Only around 10% of supernovae are of this type and they are not well understood. The fact that SN1181 was faint but faded very slowly fits this type. It is the only such event where we can study both the remnant nebula and the merged star, and also have a description of the explosion itself.”
The merging of remnant stars, white dwarfs and neutron stars, give rise to extreme nuclear reactions and form heavy, highly neutron-rich elements such as gold and platinum. Prof. Zijlstra said: “Combining all this information such as the age, location, event brightness and historically recorded 185-day duration, indicates that Parker’s star and Pa30 are the counterparts of SN 1181. This is the only Type Iax supernova where detailed studies of the remnant star and nebula are possible. It is nice to be able to solve both a historical and an astronomical mystery.”
Those that watched the movie Armageddon knew this all along!
Reassuring news for those waiting to delay the apocalypse for as long as possible: A new study suggests that our last line of defense against an asteroid hitting Earth is an effective strategy after all.
That line of defence is what’s known as a late-time small-body disruption, which is exactly what it sounds like. It’s intended to blow relatively small asteroids to pieces when we’ve had very little warning time that they’re on a collision course with Earth.
These latest calculations suggest that such a defense is “very effective” in protecting against asteroid hits when the impact time is less than a year away – so we can all sleep a little easier in our beds as a result. The Spheral simulation that was used in the analysis. (Lawrence Livermore National Laboratory)
“One of the challenges in assessing disruption is that you need to model all of the fragment orbits, which is generally far more complicated than modeling a simple deflection,” says physicist Patrick King from Johns Hopkins University in Maryland.
“Nevertheless, we need to try to tackle these challenges if we want to assess disruption as a possible strategy.”
The models that the researchers came up with looked at the impact of a 1-megaton-yield nuclear bomb hitting a 100-meter (328-foot) wide asteroid (about a fifth of the approximate size of Bennu).
Five different asteroid orbits were analyzed, with detonations performed anywhere from a week to six months before impact. For scenarios where we can hit the asteroid two months before its expected arrival, it’s possible to reduce the rain of destruction to just 0.1 percent of the original mass.
If the asteroid is a bigger pile of rock, there’s still a chance of reducing its impact mass to just 1 percent if we can hit it six months ahead of its due date.
That’s a great result, but this is still a last resort option that scientists don’t want to have to rely on: the preferred option is to deflect the asteroid away from Earth even earlier, which is a strategy that has been more fully researched and tested.
“We focused on studying ‘late’ disruptions, meaning that the impacting body is broken apart shortly before it impacts,” says King. “When you have plenty of time – typically decade-long timescales – it is generally preferred that kinetic impactors are used to deflect the impacting body.”
Figuring out where a multitude of fragments will end up once an asteroid has been blown apart is no easy task, and the team used a specialized piece of software called Spheral to figure out where these pieces of rock would be carried by gravity and other forces.
Get the calculations for blowing up an incoming object wrong, and a single asteroid impact could quickly turn into multiple impacts in several different places on Earth – the stakes couldn’t be much higher.
NASA and other agencies continue to invest in planetary defense systems, particularly when it comes to spotting potentially dangerous asteroids as early as possible. Longer timescales are crucial for maximizing our chances of pushing an asteroid off its course.
“Our group continues to refine our modeling approaches for nuclear deflection and disruption, including ongoing improvements to X-ray energy deposition modeling, which sets the initial blowoff and shock conditions for a nuclear disruption problem,” says physicist Megan Bruck Syal from the Lawrence Livermore National Laboratory (LLNL).
“This latest paper is an important step in demonstrating how our modern multiphysics tools can be used to simulate this problem over multiple relevant physics regimes and timescales.”
The research has been published in Acta Astronautica.
The ALMA image at left shows how the massive disk of gas and dust around GW Orionis is split into rings and gaps. At right, an image with SPHERE shows that the inner region is warped and twisted; the shadow of the inner ring is responsible for the dark spot near the center.ALMA (ESO/NAOJ/NRAO), ESO/Exeter/Kraus et al.
Residing 1,300 light-years away in the famous constellation Orion the Hunter is the triple-star system GW Orionis. Of its three stars, two closely orbit each other, while a third orbits the pair. These stellar triplets are young, still surrounded by a disk of dust, gas, and debris left over from their formation. And this disk, called a protoplanetary disk, has caught astronomers’ attention for several reasons — not least of which because it might harbor the first known exoplanet orbiting a trio of stars.
The disk around GW Orionis consists of three concentric rings of material, none which align with any of the orbits of the system’s three stars. Furthermore, the innermost ring doesn’t even align with the other rings, and it strangely tilts and wobbles as it orbits. And finally, there’s a big gap carved in the disk, which indicates that most the material there has been cleared out.about:blankabout:blank
Of course, researchers want to know what’s going on in GW Orionis. And a new paper published Sept. 17 in Monthly Notices of the Royal Astronomical Society may hold the answer: There’s a so-called circumtriple planet (or planets) forming within the disk, orbiting all three stars at once.
Gaps in protoplanetary disks are well known for hinting that planets are forming within them. As planets pull in nearby gas and dust to grow, they naturally clear out their surroundings. But in this case, researchers weren’t sure whether the disk’s strange behavior should be attributed to a fledgling planet or to the whirling activity of the three stars within.
As it turns out, based on 3D modeling of the system, those three stars can’t produce enough torque to clear out the gap in the disk we see. Instead, the researchers say, that gap is most likely due to at least one Jupiter-sized planet forming there. If confirmed, it would be the first ever exoplanet found to orbit three stars. (Although planets have been discovered in just over 30 triple systems to date, none of these worlds orbits all three stars.) about:blankabout:blank
The supposed planet or planets would orbit the system about 100 astronomical units (AU) from the center (1 AU is the average Earth-Sun distance). The stars themselves are much closer together. The tightly orbiting pair are separated by just 1 AU, while the third star orbits some 8 AU from the center of the system.
Because this research only provides indirect evidence for the first circumtriple planet, the next step will be actually spotting the strange world. Unfortunately, the authors conclude, that’s tricky when dealing with a system as complex as GW Orionis. Still, more observations are coming down the pike. And just maybe they will reveal a glimpse at a truly unique young world.
Einstein predicted it a century ago, scientists only just observed it.
According to Einstein’s theory of special relativity, first published in 1905, light can be converted into matter when two light particles collide with intense force. But, try as they might, scientists have never been able to do this. No one could create the conditions needed to transform light into matter — until now.
Physicists claim to have generated matter from pure light for the first time — a spectacular display of Einstein’s most famous equation.
This is a significant breakthrough, overcoming a theoretical barrier that seemed impossible only a few decades ago.
It sounds simple enough, but no one has been able to make it happen.
What does E=mc2 mean? The world’s most famous equation is both straightforward and beyond comprehension at the same time: “Energy equals mass times the speed of light squared.”
At its most fundamental level, it means energy and mass are various forms of the same thing. Energy may transform into mass and vice versa under the right circumstances.
However, imagine a light beam transforming into, say, a paper clip, and it seems like pure magic. That’s where the “speed of light squared” factors in. It determines how much energy a paper clip or any piece of matter contains. The speed of light is the factor needed to make mass and energy equal. If every atom in a paper clip could be converted to pure energy, it would generate 18 kilotons of TNT. That’s around the size of the Hiroshima bomb from 1945.
(Still can’t picture it? Me neither.)
You can go the other way, too: if you crash two highly energized light particles, or photons, into each other, then you can create energy and mass. It sounds simple enough, but no one has been able to make it happen.
The great experiment: In 1934, American physicists Gregory Breit and John Wheeler first described how to create this wild transformation. But the colliding light particles would need to be extremely powerful gamma rays, which scientists haven’t created to this day.
A team of scientists from Brookhaven National Laboratory in New York wanted to take another shot at it.
“In their  paper, Breit and Wheeler already realized this is almost impossible to do,” physicist Zhangbu Xu said in a statement. “Lasers didn’t even exist yet! But Breit and Wheeler proposed an alternative: accelerating heavy ions. And their alternative is exactly what we are doing at RHIC.”
Since they couldn’t accelerate light particles, the team opted for ions, and used the Relativistic Heavy Ion Collider (RHIC) to accelerate them at extreme speeds. In two accelerator rings at RHIC, the accelerated gold ions to 99.995% of the speed of light. With 79 protons, a gold ion has a strong positive charge. When a charged heavy ion is accelerated to incredible speeds, a strong magnetic field swirls around it.
“When the ions are moving close to the speed of light, there are a bunch of photons surrounding the gold nucleus, traveling with it like a cloud,” Xu said.
That magnetic field produces “virtual photons.” So, in a roundabout way, they accelerated light particles by piggybacking them on an ion.
When the team sped the ions in the accelerator rings with significant energy, the ions nearly collided, allowing the photon clouds surrounding them to interact and form an electron-positron pair — essentially, matter. They published their work in thejournal Physical Review Letters.
“Our results provide clear evidence of direct, one-step creation of matter-antimatter pairs from collisions of light as originally predicted by Breit and Wheeler,” Brandenburg said, reports the Daily Mail.
Ghostly gamma-ray beams blast from Milky Way’s center
As galaxies go, our Milky Way is pretty quiet. Active galaxies have cores that glow brightly, powered by supermassive black holes swallowing material, and often spit twin jets in opposite directions. In contrast, the Milky Way’s center shows little activity. But it wasn’t always so peaceful. New evidence of ghostly gamma-ray beams suggests that the Milky Way’s central black hole was much more active in the past.
“These faint jets are a ghost or after-image of what existed a million years ago,” said Meng Su, an astronomer at the Harvard-Smithsonian Center for Astrophysics, and lead author of a new paper in the Astrophysical Journal.
This artist’s conception shows an edge-on view of the Milky Way galaxy. Newly discovered gamma-ray jets (pink) extend for 27,000 light-years above and below the galactic plane, and are tilted at an angle of 15 degrees. Previously known gamma-ray bubbles are shown in purple. The bubbles and jets suggest that our galactic center was much more active in the past than it is today. (Image by David A. Aguilar)
“They strengthen the case for an active galactic nucleus in the Milky Way’s relatively recent past,” he added.
The two beams, or jets, were revealed by NASA’s Fermi space telescope. They extend from the galactic center to a distance of 27,000 light-years above and below the galactic plane. They are the first such gamma-ray jets ever found, and the only ones close enough to resolve with Fermi.
The newfound jets may be related to mysterious gamma-ray bubbles that Fermi detected in 2010. Those bubbles also stretch 27,000 light-years from the center of the Milky Way. However, where the bubbles are perpendicular to the galactic plane, the gamma-ray jets are tilted at an angle of 15 degrees. This may reflect a tilt of the accretion disk surrounding the supermassive black hole.
“The central accretion disk can warp as it spirals in toward the black hole, under the influence of the black hole’s spin,” explained co-author Douglas Finkbeiner of the CfA. “The magnetic field embedded in the disk therefore accelerates the jet material along the spin axis of the black hole, which may not be aligned with the Milky Way.”
The two structures also formed differently. The jets were produced when plasma squirted out from the galactic center, following a corkscrew-like magnetic field that kept it tightly focused. The gamma-ray bubbles likely were created by a “wind” of hot matter blowing outward from the black hole’s accretion disk. As a result, they are much broader than the narrow jets.
Both the jets and bubbles are powered by inverse Compton scattering. In that process, electrons moving near the speed of light collide with low-energy light, such as radio or infrared photons. The collision increases the energy of the photons into the gamma-ray part of the electromagnetic spectrum.
The discovery leaves open the question of when the Milky Way was last active. A minimum age can be calculated by dividing the jet’s 27,000-light-year length by its approximate speed. However, it may have persisted for much longer.
“These jets probably flickered on and off as the supermassive black hole alternately gulped and sipped material,” said Finkbeiner.
It would take a tremendous influx of matter for the galactic core to fire up again. Finkbeiner estimates that a molecular cloud weighing about 10,000 times as much as the Sun would be required.
“Shoving 10,000 Suns into the black hole at once would do the trick. Black holes are messy eaters, so some of that material would spew out and power the jets,” he said.
A physicist creates an AI algorithm that predicts natural events and may prove the simulation hypothesis.
Princeton physicist Hong Qin creates an AI algorithm that can predict planetary orbits.
The scientist partially based his work on the hypothesis which believes reality is a simulation.
The algorithm is being adapted to predict behavior of plasma and can be used on other natural phenomena.
A scientist devised a computer algorithm which may lead to transformative discoveries in energy and whose very existence raises the likelihood that our reality could actually be a simulation.
The algorithm was created by the physicist Hong Qin, from the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL).
The algorithm employs an AI process called machine learning, which improves its knowledge in an automated way, through experience.
Qin developed this algorithm to predict the orbits of planets in the solar system, training it on data of Mercury, Venus, Earth, Mars, Ceres, and Jupiter orbits. The data is “similar to what Kepler inherited from Tycho Brahe in 1601,” as Qin writes in his newly-published paper on the subject. From this data, a “serving algorithm” can correctly predict other planetary orbits in the solar system, including parabolic and hyperbolic escaping orbits. What’s remarkable, it can do so without having to be told about Newton’s laws of motion and universal gravitation. It can figure those laws out for itself from the numbers.
Qin is now adapting the algorithm to predict and even control other behaviors, with a current focus on particles of plasma in facilities built for harvesting fusion energy powering the Sun and stars. Along with Eric Palmerduca, a Ph.D. graduate student at PPPL, Qin is using his technique “to learning an effective structure-preserving algorithm with long-term stability to simulate the gyrocenter dynamics in magnetic fusion plasmas,” as he elaborated. He also plans to utilize the algorithm to study quantum physics.
Physicist Hong Qin with images of planetary orbits and computer code.
Qin explained the unusual approach taken by his work:
“Usually in physics, you make observations, create a theory based on those observations, and then use that theory to predict new observations, ” said Qin. “What I’m doing is replacing this process with a type of black box that can produce accurate predictions without using a traditional theory or law. Essentially, I bypassed all the fundamental ingredients of physics. I go directly from data to data (…) There is no law of physics in the middle.”
Qin was partially inspired by the work of Swedish philosopher Nick Bostrom, whose 2003 paper famously argued that the world we are living in may be an artificial simulation. What Qin believes he has accomplished with his algorithm is provide a working example of an underlying technology that could support the simulation in Bostrom’s philosophical argument.
In an email exchange with Big Think, Qin remarked: “What is the algorithm running on the laptop of the Universe? If such an algorithm exists, I would argue that it should be a simple one defined on the discrete spacetime lattice. The complexity and richness of the Universe come from the enormous memory size and CPU power of the laptop, but the algorithm itself could be simple.”
Certainly, the existence of an algorithm that derives meaningful predictions of natural events from data does not yet mean that we ourselves have the capabilities to simulate existence. Qin believes we are likely “many generations” away from being able to carry out such feats.
Qin’s work takes the approach of using “discrete field theory,” which he thinks is particularly well suited for machine learning, while somewhat difficult for “a current human” to understand. He explained that “a discrete field theory can be viewed as an algorithmic framework with adjustable parameters that can be trained using observational data.” He added that “once trained, the discrete field theory becomes an algorithm of nature that computers can run to predict new observations.”
Are we living in a simulation? | Bill Nye, Joscha Bach, Donald Hoffman | Big Thinkwww.youtube.com
According to Qin, discrete field theories go against the most popular method of studying physics today, which looks at spacetime as continuous. This approach was started with Isaac Newton, who invented three approaches to describing continuous spacetime, including Newton’s law of motion, Newton’s law of gravitation, and calculus.
Qin believes there are serious issues in modern research that stem from the laws of physics in continuous spacetime being expressed through differential equations and continuous field theories. If laws of physics were based on discrete spacetime, as Qin proposes, “many of the difficulties can be overcome.”
If the world works according to discrete field theory, it would look like something out “The Matrix,” made of pixels and data points.
Qin’s work also coincides with the logic of Bostrom’s simulation hypothesis and would mean that “the discrete field theories are more fundamental than our current laws of physics in continuous space.” In fact, writes Qin, “our offspring must find the discrete field theories more natural than the laws in continuous space used by their ancestors during the 17th-21st centuries.”
Only a tiny fraction of them may be habitable, though.
Arecent paper accepted by The Astrophysical Journal has gotten a lot of attention, and for good reason. Nikku Madhusudhan and his colleagues from the University of Cambridge took a close look at a novel type of habitable exoplanet, which they call Hycean worlds. These planets would fall somewhere between “Super-Earths” and “mini-Neptunes” in terms of mass. They’re thought to have enough gravity to keep a thick hydrogen atmosphere over a huge liquid water ocean.
Planets like these, floating alone in interstellar space—in other words, not orbiting a star—have previously been recognized as being potentially habitable. Madhusudhan provided a more detailed investigation, including modeling of different scenarios, and concluded that habitable temperatures and pressures would be very common on those type of planets. In fact, they argue, many of them could harbor life. The authors suggest that certain molecules indicative of life could be detected by the soon-to-launch James Webb Telescope, even though they would only exist at very low concentrations in their hydrogen-dominated atmospheres.
The authors surmised that Hycean planets up to 10 times as massive as Earth could be habitable even if tidally locked (Dark Hycean Worlds) or lacking a host star (Cold Hycean Worlds). The latter would, in principle, be like other “rogue” planets.
Given the number and variety of exoplanets already cataloged, I agree that there should be many planets that fall in the mass range between Super-Earths and mini-Neptunes. But I think only a very small fraction of these can be expected to be truly habitable, and even fewer would be capable of hosting life.
We do not have a Hycean world in our Solar System, which doesn’t mean they couldn’t be common elsewhere, of course. We do have Neptune, which is thought to have a liquid water ocean in its atmosphere. Yet that’s not a place where we look for life. Habitability requires so much more than benign temperatures and pressures to keep water liquid. It also requires an energy source, suitable organic building blocks, and a mechanism to recycle nutrients, such as plate tectonics. Even if a planet has all this, it doesn’t mean it hosts life, because there are likely many habitable, but uninhabited, planets out there.
The reason is that the constraints for life arising in the first place are much more stringent than for the persistence of life, because once it takes hold it can adapt by natural selection to a broad variety of environments, even extreme ones. And even if life does arise on Hycean worlds, don’t expect anything more than microbes. Given the lack of oxygen or some other compound to provide lots of metabolic energy, animal life is not a realistic option.
So, while I agree with the authors that we should search these proposed Hycean worlds for molecules indicative of life (so-called biosignatures), such as methyl chloride, dimethyl sulfide, and carbonyl sulfide, we shouldn’t get our hopes too high. Keep in mind that the Venusian atmosphere has lots of carbonyl sulfide, but may have no current life, and the detection of these molecules would not be conclusive.
Having said that, however, I think the authors need to be praised for suggesting possible life on worlds very different from ours. One common mistake is that we’re often too Earth-centric in our search for life in the universe.
A few will extend the moratorium by a day or two, though that decision is reportedly dependent upon the angular distance between Mars and the sun in the Earth’s sky.
Nevertheless, Mars missions will not be fully inactive during this period.
The Perseverance Mars Rover – which landed in February of this year – will take weather measurements with its MEDA (Mars Environmental Dynamics Analyzer) sensors, run its RIMFAX (Radar Imager for Mars’ Subsurface Experiment) radar, capture new sounds with its microphones and look for dust devils with its cameras.
The Curiosity Mars Rover – which has been on Mars since August 2012 – will also take weather measurements using its REMS (Rover Environmental Monitoring Station) sensors, look for dust devils with its cameras and take radiation measurements with its RAD (Radiation Assessment Detector) and DAN (Dynamic Albedo of Neutrons) sensors.
Lastly, NASA’s InSight lander will continue to use its seismometer to detect temblors and NASA’s three orbiters will all continue relaying some data from the surface missions back to Earth, as well as gather their own science.
“Though our Mars missions won’t be as active these next few weeks, they’ll still let us know their state of health,” Roy Gladden, manager of the Mars Relay Network at NASA’s Jet Propulsion Laboratory (JPL), said in a statement. “Each mission has been given some homework to do until they hear from us again.”Video
NASA noted that there would be a temporary pause in raw images available from Perseverance, Curiosity and InSight.
After the moratorium, the spacecraft will send the remaining data to NASA’s Deep Space Network: an international array of giant radio antennas managed by JPL.
NASA engineers will spend a week downloading the information before standard spacecraft operations are able to resume.
Enceladus’s unusual features could help scientists search for evidence of life outside Earth.
Saturn’s moon Enceladus sports several vast rifts (often called “tiger stripes”) near its south pole, as seen in this false-color image from the Cassini spacecraft. NASA/JPL/Space Science Institute/CICLOPS
Enceladus, Saturn’s sixth largest moon, is awash with liquid water beneath its icy shell. At the moon’s south pole, the subsurface ocean erupts from one hundred geysers located along four parallel fractures known as ‘tiger stripes.’ The towering jets of ice particles form a plume that snows back down to the surface. Some of the ice even escapes the moon’s gravity and forms Saturn’s E-ring.
Icy moons that have (or are thought to have) subsurface oceans are common in the outer solar system. For example, Jupiter has several of them. These form when gravity from the planet they orbit stretches and squeezes their interior.
Scientists think that these tidal stresses generate enough heat to sustain the liquid water. Tidal stresses can crack the ice shell, but it may be difficult for these fractures to travel all the way through. Enceladus’ tiger stripes are unusual because they extend down to the ocean — and they present an enticing opportunity to search for evidence of life outside Earth.about:blankabout:blank
The tiger stripes
These famous features are surrounded by 300-meter-high margins that form a valley-like trough up to several kilometers wide at the moon’s surface.
To understand exactly how the tiger stripes formed, researchers model ice shell fractures based on various thicknesses. “Our models show that tidal stresses can fracture the ice shell all the way through, but indirectly limit how thick the ice can be,” says Catherine Walker, a glaciologist from the Woods Hole Oceanographic Institution and lead author of a recent study published in The Planetary Science Journal.
This new research shows that fractures originating at the surface are unlikely to reach the subsurface ocean, even for thinner ice depths. But fractures that begin at the base of the ice shell have a better chance of piercing the surface, especially if they connect with cracks that originate from the top of the ice shell.
“The ocean is under pressure, so water is forced into tiny cracks at the base of the ice shell, which widens and propagates the cracks all the way up to the surface,” says Carolyn Porco, a planetary scientist and visiting scholar at the University of California, Berkeley, and former leader of the Cassini Imaging Team, who suggested this possibility with colleagues in 2014.
The recent study also found that it’s more difficult to form fractures through the entire ice shell than previously thought. Existing fractures reduce the overall amount of stress, and when this is accounted for, new ones don’t propagate as deep or as high, says Walker. “The exact ice shell thicknesses are not known — but it could just be that Enceladus’ ice shell is thinner than we think at the south pole.”about:blankabout:blank
A habitable ocean
Over a decade ago, the Cassini spacecraft flew through the plume and detected a composition of mostly water, but also salts and organic molecules that hinted at the subsurface ocean.
The spacecraft detected tiny grains of silica, too, which suggests the presence of hydrothermal vents. Temperatures may reach close to 212 degrees Fahrenheit within these vents, which would allow organisms to survive without sunlight, says Morgan Cable, a chemist who heads NASA’s Astrobiology and Oceans Worlds Group.
Like hydrothermal vents on Earth, those on Enceladus sit on the seafloor. There, heat from the moon’s rocky interior may erupt hot mineral-rich water in chimney-like ocean currents — and organisms could take advantage of the different concentrations of dissolved minerals in these streams. “We are conservative in our estimate of life due to the limited energy budget, but you could certainly have multicellular organisms such as crabs,” Cable says.
A future mission
All in all, Enceladus’ tiger stripes offer a unique opportunity to collect and analyze fresh material from a subsurface ocean without the need to dig or drill. A future mission would include repeat fly-throughs of the plume, and a possible landing on the south polar terrain to sample freshly falling material that erupts from the geysers.
Touching down on Enceladus would enable the most comprehensive search for evidence of life and allow for easier collection of materials, including repeat and varied measurements to increase scientists’ confidence levels in any discoveries, Porco explains.about:blankabout:blank
A landing could also offer detailed insights into Enceladus’ geophysical workings and help resolve open questions; for example, the ice shell thickness and the width of the fractures.
But of all the burning questions, discovering whether life exists outside of Earth is the most alluring.
“It’s only in the outer reaches of our solar system that we could be assured any life found there would represent a genesis of life that is independent of life on Earth,” Porco says. “And whether or not life has arisen independently elsewhere is the most beguiling question that we could hope to answer in exploring the solar system.”
Black holes may give us a glimpse of the underlying nature of reality.
MICHELLE THALLER: Black holes really are kind of getting to the very heart of our physics. And I believe that they’re kind of showing us the way that eventually we’re going to need different physics and new physics. People ask questions like, “What happens inside a black hole?” Or even, “What happens at the very boundary of a black hole, the event horizon, when light is absorbed?” And honestly, our physics is telling us a lot of contradictory things. And our image of what an event horizon really is may be changing. People like Stephen Hawking and Leonard Susskind have recently come up with this idea that a black hole should not be able to destroy information. O.K., what do we mean by information? Information can be almost anything.
All of the different atoms in my body have angular momentum, they have charge, they have mass. There’s all sorts of little bits of information that make me me. At the quantum mechanic level, the tiniest of levels, there are different amounts of energy, there are different probabilities that are contained in the structure of my matter. And information, in some ways is a form of energy. It’s actually a way that you can describe something which is somehow, in a strange way, a higher energy state than not being able to describe something. And so one of the questions is, “If energy really can’t be destroyed energy itself is something that is intrinsic in the universe, you can’t really created or destroy it is it possible that information is the same way? Is there really no way to actually destroy the information about what all of my subatomic particles are doing right now?”
So black holes kind of stare you right in the face. What a black hole supposedly does is it absorbs everything. Space and time bend into a black hole so that nothing can escape. That means that any information about the material that fell in is gone. The only thing we know about it is that as a black hole absorbs material, it gets more massive. It actually adds that mass to the mass of the black hole. And as that mass increases, the event horizon becomes larger. Basically, the area where space is so curved that you can’t get out begins to extend the more massive a black hole is. The most massive black holes we know of in the universe are many billions of times the mass of our sun. And the physical extent of this event horizon is about the size of our solar system, maybe like out to the planet Pluto.
So is it possible, then, if everything goes into a black hole and nothing ever comes out, space and time go inside the black hole and don’t come out? What happened to that information? And this has begun to make a lot of people wonder if we really have thought of black holes the wrong way. Maybe there isn’t an event horizon in the true sense. I actually had a friend of mine that studies black holes say, “Well, I’m not sure if they’re black. They may be very, very dark navy blue.” And what he meant by that is, maybe there are some tricks to actually get information out of a black hole. Maybe there really is some form of energy that can leak away from the black hole over time. Now, Stephen Hawking wondered if quantum effects very near the event horizon could actually separate something called virtual particles, the energy of space itself. If you’re familiar with Einstein’s equation, E equals MC squared, energy equals mass times the speed of light squared. Energy and mass are the same thing. They’re equivalent.
You can actually make mass into energy, and you can make energy into mass. Around a black hole, where there’s very hot gas, very high temperatures, very strong magnetic fields, perhaps, there’s a lot of energy. And that energy can actually manifest itself as particles, mass. And the energy always creates particle/antiparticle pairs. They’re called virtual particles. And matter and antimatter, the thing you know about it is that it annihilates immediately. So these tiny little particles come into existence, then annihilate, and you’re back to energy. And this happens all around us all the time. So, if this happens near a black hole, it’s possible one of these little particles can go into the black hole and the other one escapes. And all of a sudden, there’s a particle that shouldn’t be there. The universe basically has a new particle, energy from nowhere. And how can that work?
And the information theory people say that what happens is that energy has to come out of the black hole. The black hole’s mass begins to decrease if there is this poor little orphan particle that shouldn’t have been there in the first place. So over time, tiny particle by tiny particle, These black holes can evaporate away. And maybe there’s something about those virtual particles that contain some information about the black hole and what fell into it. It even gets stranger than that, because a lot of people think that time goes slower and slower as you approach a black hole, till, at the event horizon, time basically stops. So instead of anything really ever falling into a black hole, what the event horizon may be is some sort of shell of information.
Things are stopped in time as they fell into the black hole. And right at that boundary, there is almost kind of a sphere, a two-dimensional surface that somehow contains all the information about what’s inside the black hole. And this reminded people of something that the humans invented, called a hologram. Now, a hologram is a two-dimensional object. You can make it out of glass or a piece of film. And you shine a light through it, and all of a sudden, there seem to be three-dimensional projections. And the idea is that are we looking at some fundamental way the universe stores information. Around a black hole, where space and time have been crushed out of existence, could there be a shell of information, something like a hologram?
And a lot of people began to wonder, maybe that’s the way the universe works on a larger scale. Maybe black holes are showing us, intrinsically, what the underlying nature of reality is, that there really is a two-dimensional surface of something that contains all information about the entire universe. Maybe in some way, we are part of this giant hologram. And I should mention that the word, hologram, in no way implies that somebody made the hologram. We’re just talking about the universe may really be information contained in a two-dimensional structure, not the three dimensions that we’re aware of now. This all sounds incredibly strange. I’m always a little bit afraid to even talk about it. But I think that the thing to really kind of gain from this is that black holes are staring us right in the face. We’re now observing them.
They’re right there. And we cannot really describe how the universe should work with one of these things. They don’t make sense. The universe shouldn’t be able to lose information. So how do you get information when space itself are bent in and nothing comes out? Black holes may be the key to where the next physics has to go. We all know that we need a next Einstein, a next quantum theory, something that actually describes how gravity works in very intense situations like a black hole. Now we’re actually observing black holes well enough that we really have to get on this. We really have to figure out how the universe works around one of these things. And we may end up learning what the universe itself really is.
The scientists that found Comet Bernardinelli-Bernstein are an unlikely pair.
An image taken by the Dark Energy Survey shows Comet Bernardinelli-Bernstein in October 2017. (Image credit: Dark Energy Survey/DOE/FNAL/DECam/CTIO/NOIRLab/NSF/AURA/P. Bernardinelli & G. Bernstein (UPenn)/DESI Legacy Imaging Surveys. Acknowledgments: T.A. Rector (University of Alaska Anchorage/NSF’s NOIRLab)/M. Zamani (NSF’s NOIRLab)/J. Miller (NSF’s NOIRLab))
Even Pedro Bernardinelli and Gary Bernstein admit they’re an unlikely pair of scientists to end up with a record-breaking comet named in their honor.
Scientists briefly estimated that Comet Bernardinelli-Bernstein, as it’s now known, was the largest such icy body identified to date, perhaps more than 100 miles (160 kilometers) across. Additional observations have cast that into doubt, but given the “megacomet” a new distinction: it sprouted a tail remarkably far from the sun, suggesting more revelations to come. All told, the object offers astronomers an unprecedented opportunity to watch the antics of a comet.
But Bernardinelli spotted the object only a week or so before defending his dissertation, which focused on finding an entirely different type of outer solar system object, trans-Neptunian objects. And Bernstein’s primary scientific interest lies in another topic: looking for distortions caused by dark matter. Yet here Bernardinelli and Bernstein are, with one of the largest known comets to date named for them. They seem a little dazed by the turn of events — although they both said their parents are quite pleased with unexpected development.
“This is an unusual honor for a cosmologist,” Bernstein, an astronomer at the University of Pennsylvania, told Space.com, “but my mother’s very happy.”
A different quest
Bernardinelli’s doctoral thesis focused on identifying a class of objects called trans-Neptunian objects (TNOs), of which Comet Bernardinelli-Bernstein is distinctly not one, although his research discovered more than 800 of those as well.
TNOs are hunks of rock that, as the name implies, circle the sun but remain out beyond Neptune’s orbit. That’s about 30 times the Earth’s average distance from the sun, which is about 93 million miles (150 million km) and which scientists call an astronomical unit, or an AU. But most TNOs never stray farther from the sun than a few hundred astronomical units.
So when Bernardinelli’s analysis pulled up an object and declared that its most distant point from the sun was tens of thousands of astronomical units from the sun, he noticed.
“It immediately popped out in my eye,” Bernardinelli, who completed his doctoral work at the University of Pennsylvania this summer and is now starting a postdoc at the University of Washington, told Space.com. He remembers thinking, “‘This is weird — what is this thing?'”
The detection was so weird, in fact, that he thought it was a mistake and went looking for errors. But that quest came up empty, so he brought the find to Bernstein, his advisor. “I didn’t see anything, everything looked real,” Bernardinelli said. “It looked more real than most of the things we find.”
A lucky find
The researchers spotted Comet Bernardinelli-Bernstein in data called the Dark Energy Survey (DES), which ran on a telescope at the Cerro Tololo Inter-American Observatory in Chile from 2013 to 2019.
(“It’s not like this is the Pedro and Gary show at all,” Bernstein said. “In fact, we wanted the comet to be called Comet DES, but apparently that’s against the rules.”)
The Dark Energy Survey was, as its name implies, a survey designed to help scientists understand dark energy, a mysterious substance that scientists have not yet seen directly but is believed to make up 68% of the universe and warps our view of other galaxies. The project captured more than 80,000 images of the sky, revisiting specific patches about every two weeks. In each image are tens of thousands of cosmic objects of all shapes and sizes.
“When you take an image of the sky, you’re not taking just an image of the galaxies, you’re taking an image of everything that is between you and them, essentially,” Bernardinelli said. “So you get things like stars, you get airplanes, you get asteroids, and everything else in between.”
So Bernardinelli and Bernstein reserved time on a supercomputer and set about designing a way to spot TNOs within the Dark Energy Survey images. Using the time and location of each image to stack up solar system views, the researchers set the algorithm to identify when at least seven different images lined up to show a speck moving according to the laws that govern the movement of solar system objects.
“It’s a massive connect-the-dots.” Bernardinelli said.
“We knew it was real right away.”— Gary Bernstein, astronomer
Although seven different images was the minimum setting, the massive comet turned up in 20 or 30 separate images, Bernstein said. “There’s absolutely no way you could get that by accident,” he said. “We knew it was real right away.”
But in fact, the algorithm still shouldn’t have flagged the object, he noted. Bernardinelli and Bernstein had set the program to look for objects located at least 30 AU from the sun, around where Neptune orbits. That setting was a matter of convenience — it matches the location of the TNOs that were the researchers’ main goal and closer images are tricky to identify with two weeks often stretching between images.
When the survey was operating, however, the comet was already closer — only 25 AU from the sun by 2017. (According to the orbital calculations, the closest Bernardinelli-Bernstein will come to the sun is about 11 AU — still more distant than Saturn‘s orbit — in 2031.)
“It was a little bit of luck that we caught it,” Bernstein said, adding that the luck likely was a result of the object being so easy to see.
Cause for excitement
Although what initially stood out to Bernardinelli was the comet’s weird orbital characteristics, the discovery made such a splash because of a different trait, the comet’s estimated size. Based on the object’s brightness and distance, the scientists initially estimated that the comet’s nucleus — the icy rock at its core — was 60 to 120 miles (100 to 200 kilometers) wide.
Ironically, if the detection had turned out to be one of the TNOs the study was really targeting, it would have been unremarkable, since scientists know of plenty of TNOs of that size. But as far as comets go, that size estimate is truly massive. Among the comets scientists have studied in detail, only two are in the same class: Comet Hale-Bopp, which made a close approach to Earth in 1997, and Comet C/2002 VQ94 (LINEAR), which came no deeper into the solar system than Jupiter’s orbit.
Large comets are rare because the same vaporizing ice that makes them so spectacular to see robs them of their being, so every pass by the sun leaves the comet a little bit smaller than before.
“It’s very rare to see big comets basically because unless you’re catching it in its first or second passage, most of its material would already be gone,” Bernardinelli said.
However, scientists have always expected objects like Comet Bernardinelli-Bernstein to exist, wandering the frigid edges of the solar system for eons. And outside experts say that not only is the discovery not surprising, but it’s also a sign that scientists are on the right track in piecing together the history of the solar system.
“It’s neat but not that unexpected,” Meg Schwamb, a planetary astronomer at Queen’s University Belfast in Northern Ireland who specializes in the outer solar system and wasn’t involved in the discovery, told Space.com. “It fits in with the story we know.”
That story goes like so: The young solar system sported a ring of small, icy rubble surrounding the massive planets. But when the planets migrated through the solar system, their huge gravity kicked the frozen rubble around.
Some flew out into interstellar space; some ended up in what scientists call the Kuiper Belt, where Pluto orbits; some ended up in the much more distant Oort Cloud where comets like Bernardinelli-Bernstein lurk. From there, as tides flow through the Milky Way and neighboring stars pass our solar system, gravity occasionally kicks a snowball inward on a planetary adventure.
And there are plenty of Kuiper Belt objects that look like the new comet, Schwamb said, so finding a similar object coming in from the Oort Cloud suggests scientists have been on the right path, and that more discoveries are still to come.
“Finding one large object like this probably means there’s a few more out there to be found,” Schwamb said.
As more eyes spotted the new comet, its story changed a little.
Scientists turned their telescopes to the object’s modern location and combed through archival data to rescue sightings that were missed in original analysis. And in those objects, it was clear that Comet Bernardinelli-Bernstein wasn’t fully frozen and had already woken up a little by the time it first appeared in scientists’ images.
Comets grow their distinctive fuzzy comas when their ices warm up enough to vaporize away into a gaseous cloud surrounding the nucleus. The phenomena obscures the nucleus and brightens the comet — which means that if Comet Bernardinelli-Bernstein was active in even the earliest sightings, scientists had overestimated its size.
“Comets like to surprise us.”— Rosita Kokotanekova, comet scientist
It’s a common challenge for scientists who focus on studying a comet’s nucleus proper, Rosita Kokotanekova, a cometary scientist at the European Southern Observatory who was not involved in the discovery of the new comet, told Space.com. “Comets like to surprise us,” she said. “You make the assumption that you’re studying the nucleus, but you might be tricked by the surrounding coma.”
Calculating the size of an active comet is much more complicated than measuring a bare nucleus, it turns out, so Kokotanekova said she couldn’t offer a new size estimate for the comet, beyond that it would be somewhat smaller than the original calculations.
But despite the slightly less superlative size, Comet Bernardinelli-Bernstein remains a stunner, she said — for the very same activity that invalidated the original size estimate. Scientists have only spotted a handful of comets active so far from the sun, where temperatures are still too cold for, say, water ice to turn to vapor, a typical type of cometary activity. Good observations of an active comet so far away could teach scientists about unknown types of cometary antics, she said.
“Usually there we have very few objects that are active, and we catch even fewer,” Kokotanekova said. “What’s really unique about this object is not its size but how active it is at these large distances and what a great opportunity it gives us to characterize distant activity.”
A gift for years to come
Regardless of size and activity, all the scientists agreed that the most exciting aspect of Comet Bernardinelli-Bernstein is how well scientists will be able to study it.
A few different factors make the comet particularly promising. First, given a 2021 discovery and a 2031 close approach to the sun — plus old observations from as early as 2010 — gives scientists a decades-long look at the object that’s rare for this class of comet that makes such long journeys.
“Studying long-period comets is more complicated,” Kokotanekova said, compared to short-period comets that never stray so far from the sun. “They just pass through the solar system, we catch them quite late on, and then we study them for a brief period. And then they’re gone forever.”
And much of Comet Bernardinelli-Bernstein’s journey, scientists will have practically continuous views, thanks to the Vera C. Rubin Observatory in Chile scheduled to begin observing in 2023. That facility will survey the southern sky once every three days, offering astronomers an impeccably detailed view of how the comet changes as it approaches the sun.
“We’re going to get an entire movie of this object as it evolves and comes inward,” Schwamb said. Kokotanekova hopes that, in particular, the movie will teach astronomers what types of activity turn on and at what distances from the sun.
Although they didn’t set out to find such an important comet, both Bernardinelli and Bernstein said that their unexpected discovery this summer has given them a new appreciation for the dirty iceballs rattling around the outer solar system.
“I will still have my day job, I think, of cosmology,” Bernstein said. But still, “it’s been enjoyable, I’ve really learned a lot about comets.”
For Bernardinelli, however, the chance encounter with the comet that now carries his name may change his own scientific trajectory, he said. “I had never thought too hard about comets before, and as I move on to the postdoc stage I get to expand the types of things that I do, so I’m definitely considering branching into comets more.”
NASA has delayed their Artemis mission to the Moon, but that doesn’t mean a return to the Moon isn’t imminent. Space agencies around the world have their sights set on our rocky satellite. No matter who gets there, if they’re planning for a sustained presence on the Moon, they’ll require in-situ resources.
Oxygen and water are at the top of a list of resources that astronauts will need on the Moon. A team of engineers and scientists are figuring out how to cook Moon rocks and get vital oxygen and water from them. They presented their results at the Europlanet Science Congress 2021.
Professor Michèle Lavagna of Politecnico Milano led the experiments. A consortium of companies and agencies, including the ESA and the Italian Space Agency, is behind the work. Lavagna and others presented a laboratory demonstration of their work at EPSC2921.
When we talk about lunar soil, we mean lunar regolith, the layer of dust that coats the Moon. The same layer that confounded Apollo astronauts by finding its way into the lunar module, clogging mechanisms and interfering with instruments. The dust constitutes an ongoing hazard that space agencies are still trying to mitigate. But the same dust is also a critical resource.
There’s lots of oxygen in the lunar regolith because oxygen readily reacts with other elements, especially group one elements. Lunar soil is rich in oxides, especially silicon dioxide, iron oxide, magnesium oxide, etc. According to the ESA, about 50% of lunar soil is iron and silicon dioxide, and about 26% of those compounds are oxygen. The trick is getting the oxygen out.
Lavagna demonstrated a two-step process that’s regularly used in industrial applications here on Earth. First, the simulated lunar regolith is vaporized in the presence of hydrogen and methane then washed with hydrogen gas. A furnace heats the minerals to 1,000 Celsius (1800 F), which turns them directly from a solid to a gas. By doing so, the minerals skip the liquid phase, making the entire process simpler.
Then the gases and the residual methane go to a catalytic converter and then a condenser which separates the water. After that, hydrolysis separates the oxygen, and the system recycles the hydrogen and methane by-products.
Engineers and scientists have been working on the challenge of extracting in-situ resources on the Moon for many years now. One method involves using molten salt electrolysis to extract oxygen. That method is adapted from mining, and it also produces useful metal alloys from lunar regolith.
But one of the critical features of this newer process, according to Lavagna, is it’s almost hands-off.
“Our experiments show that the rig is scalable and can operate in an almost completely self-sustained closed loop, without the need for human intervention and without getting clogged up,” said Professor Lavagna. https://player.vimeo.com/video/612528519 This video shows water extracted by the process. Credit: Politecnico Milano, CC BY-NC-CD
The team is still working on optimizing the process in anticipation of an eventual fight test. They’re working with the furnace temperature, length and frequency of the washing, the ratio of the gas mixtures, and the size of soil batches. So far, they’ve learned that small batches of soil produce maximized yields when combined with the highest possible temperatures and long washing phases.
The system produces silica as a by-product. It also produces metals that require further processing before being used as in-situ resources.
‘The capability of having efficient water and oxygen production facilities on-site is fundamental for human exploration and to run high-quality science directly on the Moon,’ said Lavagna. ‘These laboratory experiments have deepened our understanding of each step in the process. It is not the end of the story, but it’s a very good starting point.
The universe holds the most breathtaking spectacles. Whether it’s light displays, solar and lunar eclipses, or glimmering meteor showers, the natural phenomena that regularly occur in space leave us in awe time and again. While some events can be observed quite frequently in the night sky, other galactic events occur at intervals of several thousand years. Experts are therefore all the more delighted when they manage to observe such a rare phenomenon firsthand.
Scientists track meteor shower to unusual comet seen every 4,000 years
The meteoroid stream of Comet Thatcher. (Image credit: P. Jenniskens/SETI Institute)
Meteor showers are the dazzling result of cometary debris building up along well-worn paths through the solar system, then burning up in Earth’s atmosphere as our planet crosses that dust trail.
It’s hard to call a path well-worn when something passes by only once every 3,967 years. But it turns out that type of long-period comet can still be tied to a specific meteor shower, as scientists have done with Comet C/2002 Y1 Juels-Holvorcem and the UY Lyncids shower. The research that connected the long haul ice ball and the shower triples the number of celestial displays that scientists have tied to specific comets that take more than 250 years to orbit the sun.
“Until recently, we only knew five long-period comets to be parent bodies to one of our meteor showers,” Peter Jenniskens, a meteor astronomer at the SETI Institute and the lead author of the new research, said in a statement. “But now we identified nine more, and perhaps as many as 15.”
For some perspective, Comet C/2002 Y1 Juels-Holvorcem most recently made a close approach of the sun in 2003 — which means its last such visit was around 2,000 B.C., when Egypt’s Great Pyramids were just a few hundred years old, and its next pass of the sun won’t occur until nearly the year 6,000.
Typically, a shorter orbit means a comet retraces its path more regularly, scattering more rubble that can become more “shooting stars” when Earth plows through the debris. That means it’s difficult for skywatchers to notice meteor showers caused by comets with orbits beyond about 250 years or so.
The best known long-period comet that triggers a meteor shower is comet C/1861 G1 Thatcher, which causes the April Lyrid meteor shower. Other long-period comets’ showers are less dramatic, even those scientists had previously identified, like the Aurigids (debris from C/1911 N1 Kiess) and the Leonis Minorids (from C/1739 K1 Zanotti).
The scientists behind the new study wanted to find more such connections, so they turned to a program called Cameras for Allsky Meteor Surveillance (CAMS), which includes observation stations across the United States and around the globe, including in New Zealand, Namibia, Chile and the United Arab Emirates — networks totalling more than 500 individual cameras all told, all watching for meteors.
“These are the shooting stars you see with the naked eye,” Jenniskens said. “By tracing their approach direction, these maps show the sky and the universe around us in a very different light.”
Looking at such huge amounts of meteor sightings, scientists can pick out subtle meteor showers based on tracking only a few shooting stars to similar origin points in the sky, called radiants. So astronomers combined that analysis of a decade of observations with NASA’s database of comets and their orbits.
The scientists found at least nine new matches between meteor showers and long-period comets, and identified another six potential matches. The research tracks down the comets responsible for esoteric meteor showers, like December’s sigma Virginids and July’s Pegasids, caused by debris from C/1846 J1 Brorsen and C/1979 Y1 Bradfield respectively.
Most of the comets in the research swing past the sun every 400 to 800 years or so, a quite respectable calendar. Three comets joined Juels-Holvorcem is a bit of an outlier with orbits longer than 1,000 years. Scientists have tied a few other long-period comets to specific meteor showers, but can’t quite pin down their orbital periods.
Among the meteor showers studied, the researchers noticed an intriguing trend: Displays from long-period comets tend to last several days, and the radiant appears to move like a smudge on the sky. The scientists on the new research think the effect may be caused by a comet’s orbit shifting between loops, so that the rubble fields don’t align as cleanly as they do for short-period comets.
“This was a surprise to me,” Jenniskens said. “It probably means that these comets returned to the solar system many times in the past, while their orbits gradually changed over time.”
The research is described in a paper that will be published this autumn by the journal Icarus.
Scientists have begun studying the samples returned from the Moon by China’s Chang’e-5 mission in December 2020, and a group of researchers presented their first findings at the Europlanet Science Congress (EPSC) last week.
“The Chang’e-5 samples are very diverse, and includes both local and exotic materials, including some glutenates [sharp, jagged lunar particles], silicas, salts, volcanic glasses, and impact glasses, along with different minerals and different rock types,” said Yuqi Qian, a PhD student at the China University of Geosciences, during his presentation at the EPSC virtual meeting.
Chang’e-5 landed on the near side of the Moon in the Oceanus Procellarum, or Ocean of Storms, which is located on the western, central part of the Moon from our vantage point on Earth. It landed in an area not visited by the NASA Apollo or the Soviet Luna missions nearly 50 years ago. This area is also one of the youngest lunar surfaces, with an age of about 2 billion years old, and therefore these samples are different to those returned in the 1960s and 70s.
“The samples are very diverse, as we have known for a very long time that the formation of the lunar surface is a very complex process, including solar wind implantation, micrometeorite impacts, and condensation,” Qian said.
The “local” materials, which make up about 90 per cent of the returned samples, include young mare basalts, and local impact ejecta. The “exotic” materials, i.e., materials not native to the region, make up about 10 per cent of the Chang’e-5 samples and include distant impact ejecta, meteoritical materials, and volcanic glass beads.
Qian and colleagues from Brown University and the University of Münster have looked at the potential sources of the glass beads, and have traced these rapidly cooled glassy droplets to now-extinct volcanic vents known as ‘Rima Mairan’ and ‘Rima Sharp’ located roughly 230 and 160 kilometers southeast and northeast of the Chang’e-5 landing site. These fragments could give insights into past episodes of energetic, fountain-like volcanic activity on the Moon.
The team also looked at the potential sources of impact-related fragments. The young geological age of the rocks at the landing site narrows the search, as only craters with ages less than 2 billion years can be responsible, and these are relatively rare on the lunar near-side.
The team modeled what craters could be responsible for the exotic materials and found that some materials could have been ejected from as far as 1,300 km away from the Chang’e-5 landing site. They found that Harpalus, located farther north of Chang’e-5’s site, is a significant contributor of many exotic fragments among the samples, along with craters to the south and southeast (Aristarchus, Kepler, and Copernicus), and northwest (Harding).
Modelling and review of work by other teams has linked other exotic pieces of rock to domes rich in silica or to highland terrains that surround the landing site.
“All of the local and exotic materials among the returned samples of Chang’e-5 can be used to answer a number of further scientific questions,” said Qian, in a press release. “In addressing these we shall deepen our understanding of the Moon’s history and help prepare for further lunar exploration.”
Lead image caption: Image of the Chang’e-5 sample “CE5C0400” from the Moon’s surface. This fraction of lunar materials returned to Earth by Chang’e-5 weighs nearly 35 grams and was collected by a robotic arm. Credit: CNSA (China National Space Administration) / CLEP (China Lunar Exploration Program) / GRAS (Ground Research Application System).
NASA, MIT and DARPA Researchers Meet to Discuss ‘Antigravity’ Technologies
NASA, MIT and DARPA Researchers Meet to Discuss ‘Antigravity’ Technologies.
Antigravity is the idea of a technology, applied to an object or to a space, making it possible to “cancel” gravity – and not to compensate for it as is the case with an airplane for example. Since November 2020, a number of scientists from NASA, DARPA, MIT and the Air Force have been meeting regularly on Zoom to discuss propulsion technologies of the future, including the hypothetical “antigravity”. An astonishing event given that for the moment this technology remains only in the world of science fiction or in the minds of a few dreamy theorists.
The event, dubbed the Alternative Propulsion Engineering Conference ( APEC ), was created to give scientists the opportunity to discuss taboo (even wacky) ideas that go beyond the confines of current modern science.
According to information gathered by The Debrief, 22 meetings have taken place since then, during which scientists addressed topics ranging from non-Newtonian propulsion ( Em Drive ) to the observation of unidentified aerial phenomena (UAPs). In other words, in the words of Ron Kita, founder of Chiralex – a company that develops “gravity shielding” materials, this is the “Woodstock of gravity manipulation research”.
Recreation course for engineers or a serious scientific conference?
“The alternative propulsion community is highly cross-sectoral, and we are sandwiched between the cultures of aerospace, defense, electrical engineering, physics, UFOs and advanced science,” said Tim Ventura, moderator and conference organizer, at The Debrief.
“People from all these cultures come to the conference and make presentations, despite the fact that these different communities do not always agree on certain topics. We have managed to avoid conflicts,” he added. Reading these words, one can understand that the conference serves above all as a place for the exchange of ideas or personal work on one or another of the technologies discussed.
But it should still be noted that 16 of the 71 participants in the November event were current or former NASA scientists and engineers, according to The Debrief , and 14 others were affiliated with reputable institutions, including MIT and the ‘Harvard University. Among these marginal theorists, it is therefore very likely that one can find brilliant and realistic ideas.
The dream of defying gravity
As might be expected, this environment has created a sort of “virtual club” where highly skilled physicists and engineers can discuss their theories and experiences of antigravity without risking exposure to scientific skepticism. public. “Originally it was to be called the ‘Antigravity Conference’,” says Mark Sokol, founder of APEC, of the name of the conference, “but we thought antigravity had a too negative connotation”.
The possibility of creating antigravity technology depends on the full understanding and description of gravity, as well as its interactions with other physical theories, such as general relativity and quantum mechanics. In 2021, physicists have yet to develop a quantum theory of gravity. Theoretical quantum physicists have postulated the existence of a particle of quantum gravity, the graviton. Various theoretical explanations of quantum gravity have been created, including superstring theory, loop quantum gravity, E8 theory, and asymptotic security theory, among others.
Mark Sokol is also the founder of Falcon Space, based in New Jersey (United States). He had in particular launched, with his company, in the development of a “gravitational distortion detector” (the “Warp Drive Detector”) and of the first “antigravity plane in the world”. “The Warp Drive Detector was designed by Jeremiah Popp [also active in Falcon Space] and myself,” Sokol said. “The idea is to determine if a distortion field is created, to see if something changes the speed of light near an experiment.” The theoretical device would therefore serve to help the Falcon Space team in its experiments on gravity.
Sokol and his colleague Jeremiah Popp’s painstaking analysis of the scientific literature guided them to a series of previously published antigravity experiments by Frederick Alzofon, the man who theorized the idea in 1981, when he worked for Boeing, then which allegedly performed tests in the 1990s.
Hoping to improve on this questionable but nonetheless encouraging first trial, Sokol said he plans to improve the equipment, including a recently purchased magnetic resonance generator which he says “looks like an MRI machine.” and whose retail price can reach $ 60,000. Thanks to this newer and more powerful generator, he hopes to be able to repeat his experiments with results “two to three times” better than the background noise.
In an experiment conducted by Alzofon, a sample would have lost 80% of its weight in one second, according to Sokol. However, these experiments did not convince other scientists, and one engineer in particular, David Prutchi pointed out that the experiments were flawed and that Alzofon’s results were “invalid.” “Any physicist or engineer would immediately understand that the experimental data shows absolutely no effect on the gravitational force experienced by the sample,” Prutchi said in the paper. “I congratulate David Alzofon (the son of Frederick Alzofon)for its honesty by including the AF2004 graph, because not only does it invalidate the purported experimental demonstration of the effect, but it actually provides negative evidence against it,” he added.
More recently, the Gravity Research Institute of the Göde Scientific Foundation attempted to replicate experiments believed to generate an antigravity effect. However, all attempts to observe anti-gravity effects have been unsuccessful. The foundation offered a reward of one million euros for a reproducible anti-gravity experiment. In 1989, the team of Professor Hayakawa of Tohoku University of Technology in Japan, identified an abnormal reduction in the weight of a gyroscopically rotating mass to the right of the vertical axis of the Earth. This discovery was the subject of a publication in the journal Physical Review Letters. However, “left rotations do not cause any change in weight”, Concluded the researchers.
To sum up, despite obvious efforts within the scientific community, gravity remains undefeated for the time being. But who knows, maybe that might change someday, when we get a better understanding of exactly what gravity is and what it involves. Answers will undoubtedly be provided by new theories and experiments in quantum physics. And for that, the fact that qualified researchers from different backgrounds discuss it openly and regularly, is a good thing.
UFOs: a recurring subject The subject of UFOs (or PANs) apparently caused a stir at the November conference. The topic made a significant resurgence in pop culture this year, with military pilots speaking openly about unexplained encounters and the Pentagon teasing a long-awaited report on the matter, which was finally released in June.
“In the past, everyone was aware of UFOs, but they weren’t very relevant because they weren’t well understood,” Ventura told The Debrief, adding that the scientific community is exploring the subject more seriously than ever.
As the strongest gravitational force next to the sun, this isn’t that uncommon. But it serves to remind us that, while the Earth isn’t moving in a shooting gallery of apocalyptic asteroids, asteroid detection technology must continue to expand, lest one day we awake to learn it’s the last any of us will ever live before an extinction-level impact.
Jupiter gets punched in the face a lot
On September 13, 2021, at roughly 6:39 PM EDT, amateur astronomers monitored and recorded a colossally bright flash of what seemed to be an impact on Jupiter. Harald Paleske of Germany was recording the shadow of Jupiter’s moon, Io, as it passed in front of the planet. But other astronomers involved included José Luis of Brazil, Michel Jacquesson and Jean-Paul Arnould in France, Simone Gelelli of Italy, and Didier Walliang and Alexis Desmougin of the Société Lorraine d’Astronomie, also on France. Many also filmed the event, and suspect an impact on Jupiter.
While still unconfirmed, the putative event would mark only the eighth impact witnessed on Jupiter since the initial impact of Shoemaker-Levy 9 in 1994, which disintegrated into separate parts as Jupiter’s immense tidal forces ripped it open, transforming the singular asteroid into a rapid-fire event of glorious mayhem. Sadly, no one on Earth was able to see the explosions, since the impacts happened on Jupiter’s far side. But a 7.2-ft (2.2-m) Hawaii-based telescope photographed the heat signatures of each impact site as they swiveled into view. The Hubble Space Telescope also snapped grim pictures of the dark, bruise-colored smears strewn beneath the clouds, aptly named “scars.”
NASA is upgrading Earth’s planetary defense against NEOs
As of writing, scientists are unsure how often Jupiter is impacted by something so massive or high-velocity that it generates an impact flash we can see from Earth, but the consensus is it’s fairly often; between 20 and 60 times every year. If the Earth experienced significant impacts with the same frequency, its surface might look very different, and so would whatever survived. But luckily, Jupiter’s unconscionably strong gravitational field is gigantic, and accelerates incoming meteorites to unkind speeds, multiplying the kinetic energy of the incoming bodies by several orders of magnitude, which is proportional to the level of energy released upon impact (think of how baseballs hurt more if they slam into you with greater speed).
But Jupiter doesn’t take every cosmic hit headed Earth’s way. Some scientists suspect we’re overdue for another asteroid impact of a similar scale to the one that spelled doom for the dinosaurs. These happen once every 50 to 60 million years. Lucky for us, NASA gave the green light for a new space telescope, called the Near-Earth Object Surveyor (NEO Surveyor), in June. And it’s designed to upgrade Earth’s planetary defense network by detecting cosmic bodies with potentially dangerous orbital trajectories. “[W]e think there are about 25,000 NEOs large enough to wipe out an area like Southern California,” said NEO Survey Project Leader Amy Mainzer in a statement from the University of Arizona. “Once they get bigger than about 450 feet in diameter, they can cause severe regional damage. We want to find these, and as many smaller ones as possible.” This could take a few years to launch, and we have other means of detecting NEOs. But whenever a monumental impact flashes from the cloud tops of Jupiter, remember: That might have been us.
Scientists are worried our sun is preparing to pump out a massive solar event that could knock out the internet for months.
Earth’s ionosphere does a wonderful job defending us from solar winds ejected from the sun and deflects them to our poles (which cause the incredible northern and southern lights), however this system wouldn’t be able to fully stop rays from a humungous coronal mass ejection (CME).
CMEs consist of electrically conducting plasma emitted from the sun and, if they’re big enough, they can race towards the earth at 2,000km/s. It would only take a few days for it to reach us.
Because they’re electrically conducting, they have the potential to affect anything that is powered by electricity, which is essentially everything we hold dear to us these days.
Information presented at the SIGCOMM 2021 data communication conference has warned the world is not ready for such an event and could be catastrophic to modern life.
Sangeetha Abdu Jyothi, an assistant professor at the University of California, explained in her paper that an ‘internet apocalypse’ could last for a long time.
She told WIRED: “What really got me thinking about this is that with the pandemic we saw how unprepared the world was.
“There was no protocol to deal with it effectively, and it’s the same with internet resilience. Our infrastructure is not prepared for a large-scale solar event.”
She has warned that a particularly massive CME could ’cause large-scale Internet outages covering the entire globe and lasting several months’.
Our central celestial body pushes out a supermassive coronal mass ejection roughly once a century.
Back in May 1921, there were reports of fires breaking out in power control rooms in the UK and US, while places all over the world suffered problems with their electricity.
It caused the most vivid Aurora Borealis in three decades and brought some places to a standstill.
Jeffrey Love, a Geophysicist in the Geomagnetism Program of the US Geological Survey (USGS), told The Independent our world has developed massively in the last 100 years and a solar event similar to 1921 would cause carnage.
“The effects were in terms of interference to radio communications, telegraph, and telephone systems, all of which were used in 1921,” he said.
“When we look back at this time, anything that’s related to electricity wasn’t as important in 1921 as it is today.”
Dr. Scott McIntosh, deputy director of the National Center for Atmospheric Research, added that we should expect a CME aimed at earth soon.
“We have every reason to believe that the current solar cycle which began in December 2019 could be the most active since the 1970s. This is a particular concern for the GPS,” he told NextGov.com.
“Strong solar storms can charge the atmosphere and prevent signals from getting through for days. The strongest can damage or even destroy satellites.”
If you can time travel, please tell Stephen Hawking we said hi.
Is time travel possible? Short answer: Yes, and you’re doing it right now — hurtling into the future at the impressive rate of one second per second. You’re pretty much always moving through time at the same speed, whether you’re watching paint dry or wishing you had more hours to visit with a friend from out of town.
But this isn’t the kind of time travel that’s captivated countless science fiction writers, or spurred a genre so extensive that Wikipedia lists nearly 400 titles in the category “Movies about Time Travel.” In franchises like “Doctor Who,” “Star Trek,” and “Back to the Future” characters climb into some wild vehicle to blast into the past or spin into the future. Once the characters have traveled through time, they grapple with what happens if you change the past or present based on information from the future (which is where time travel stories intersect with the idea of parallel universes or alternate timelines).
Although many people are fascinated by the idea of changing the past or seeing the future before it’s due, no person has ever demonstrated the kind of back-and-forth time travel seen in science fiction, or proposed a method of sending a person through significant periods of time that wouldn’t destroy them on the way. And, as physicist Stephen Hawking pointed out in his book “Black Holes and Baby Universes” (Bantam, 1994), “The best evidence we have that time travel is not possible, and never will be, is that we have not been invaded by hordes of tourists from the future.”Click here for more Space.com videos…
Science does support some amount of time-bending, though. For example, physicist Albert Einstein’s theory of special relativity proposes that time is an illusion that moves relative to an observer. An observer traveling near the speed of light will experience time, with all its aftereffects (boredom, aging, etc.) much more slowly than an observer at rest. That’s why astronaut Scott Kelly aged ever so slightly less over the course of a year in orbit than his twin brother who stayed here on Earth.
There are other scientific theories about time travel, including some weird physics that arise around wormholes, black holes and string theory. For the most part, though, time travel remains the domain of an ever-growing array of science fiction books, movies, television shows, comics, video games and more.
SPECIAL RELATIVITY AND TIME TRAVEL TO THE NEAR FUTURE
Einstein developed his theory of special relativity in 1905. Along with his later expansion, the theory of general relativity, it has become one of the foundational tenets of modern physics. Special relativity describes the relationship between space and time for objects moving at constant speeds in a straight line.
The short version of the theory is deceptively simple. First, all things are measured in relation to something else — that is to say, there is no “absolute” frame of reference. Second, the speed of light is constant. It stays the same no matter what, and no matter where it’s measured from. And third, nothing can go faster than the speed of light.
From those simple tenets unfolds actual, real-life time travel. An observer traveling at high velocity will experience time at a slower rate than an observer who isn’t speeding through space.
While we don’t accelerate humans to near-light-speed, we do send them swinging around the planet at 17,500 mph (28,160 km/h) aboard the International Space Station. Astronaut Scott Kelly was born after his twin brother, and fellow astronaut, Mark Kelly. Scott Kelly spent 520 days in orbit, while Mark logged 54 days in space. The difference in the speed at which they experienced time over the course of their lifetimes has actually widened the age gap between the two men.
“So, where[as] I used to be just 6 minutes older, now I am 6 minutes and 5 milliseconds older,” Mark Kelly said in a panel discussion on July 12, 2020, Space.com previously reported. “Now I’ve got that over his head.”
GENERAL RELATIVITY AND GPS TIME TRAVEL
The difference that low earth orbit makes in an astronaut’s life span may be negligible — better suited for jokes among siblings than actual life extension or visiting the distant future — but the dilation in time between people on Earth and GPS satellites flying through space does make a difference.
The Global Positioning System, or GPS, helps us know exactly where we are by communicating with a network of a few dozen satellites positioned in a high Earth orbit. The satellites circle the planet from 12,500 miles (20,100 kilometers) away, moving at 8,700 mph (14,000 km/h).
According to special relativity, the faster an object moves relative to another object, the slower that first object experiences time. For GPS satellites with atomic clocks, this effect cuts 7 microseconds, or 7 millionths of a second, off each day, according to American Physical Society publication Physics Central.
Then, according to general relativity, clocks closer to the center of a large gravitational mass like Earth tick more slowly than those farther away. So, because the GPS satellites are much farther from the center of Earth compared to clocks on the surface, Physics Central added, that adds another 45 microseconds onto the GPS satellite clocks each day. Combined with the negative 7 microseconds from the special relativity calculation, the net result is an added 38 microseconds.
This means that in order to maintain the accuracy needed to pinpoint your car or phone — or, since the system is run by the U.S. Department of Defense, a military drone — engineers must account for an extra 38 microseconds in each satellite’s day. The atomic clocks onboard don’t tick over to the next day until they have run 38 microseconds longer than comparable clocks on Earth.
Given those numbers, it would take more than seven years for the atomic clock in a GPS satellite to unsync itself from an Earth clock by more than a blink of an eye. (We did the math: If you estimate a blink to last at least 100,000 microseconds, as the Harvard Database of Useful Biological Numbers does, it would take thousands of days for those 38 microsecond shifts to add up.)
This kind of time travel may seem as negligible as the Kelly brothers’ age gap, but given the hyper-accuracy of modern GPS technology, it actually does matter. If it can communicate with the satellites whizzing overhead, your phone can nail down your location in space and time with incredible accuracy. Click here for more Space.com videos…
CAN WORMHOLES TAKE US BACK IN TIME?
General relativity might also provide scenarios that could allow travelers to go back in time, according to NASA. But the physical reality of those time-travel methods are no piece of cake.
Wormholes are theoretical “tunnels” through the fabric of space-time that could connect different moments or locations in reality to others. Also known as Einstein-Rosen bridges or white holes, as opposed to black holes, speculation about wormholes abounds. But despite taking up a lot of space (or space-time) in science fiction, no wormholes of any kind have been identified in real life.
“The whole thing is very hypothetical at this point,” Stephen Hsu, a professor of theoretical physics at the University of Oregon, told Space.com sister site Live Science. “No one thinks we’re going to find a wormhole anytime soon.”
Besides the absence of identifiable wormholes, another obstacle in the way of wormhole time travel is their hypothetical size. Primordial wormholes are predicted to be infinitesimally small, about 10^-34 inches (10^-33 centimeters) at the “mouth” of the tunnel. As the universe expands, it’s possible that wormholes could stretch along with it, but other problems take hold.
Even hypothetical wormholes are expected to be extremely unstable, Hsu said, blinking in and out of existence before anything could travel through them.
“You would need some very exotic type of matter in order to stabilize a wormhole,” Hsu added, “and it’s not clear whether such matter exists in the universe.”
ALTERNATE TIME TRAVEL THEORIES
While Einstein’s theories appear to make time travel difficult, some researchers have proposed other solutions that could allow jumps back and forth in time. These alternate theories share one major flaw: As far as scientists can tell, there’s no way a person could survive the kind of gravitational pulling and pushing that each solution requires.
Infinite cylinder theory
Astronomer Frank Tipler proposed a mechanism (sometimes known as a Tipler Cylinder) where one could take matter that is 10 times the sun’s mass, then roll it into a very long, but very dense cylinder. The Anderson Institute, a time travel research organization, described the cylinder as “a black hole that has passed through a spaghetti factory.”
After spinning this black hole spaghetti a few billion revolutions per minute, a spaceship nearby — following a very precise spiral around the cylinder — could travel backwards in time on a “closed, time-like curve,” according to the Anderson Institute.
The major problem is that in order for the Tipler Cylinder to become reality, the cylinder would need to be infinitely long or be made of some unknown kind of matter. At least for the foreseeable future, endless interstellar pasta is beyond our reach.
Theoretical physicist Amos Ori at the Technion-Israel Institute of Technology in Haifa, Israel, proposed a model for a time machine made out of curved space-time — a donut-shaped vacuum surrounded by a sphere of normal matter.
“The machine is space-time itself,” Ori toldLive Science. “If we were to create an area with a warp like this in space that would enable time lines to close on themselves, it might enable future generations to return to visit our time.”
There are a few caveats to Ori’s time machine. First, visitors to the past wouldn’t be able to travel to times earlier than the invention and construction of the time donut. Second, and more importantly, the invention and construction of this machine would depend on our ability to manipulate gravitational fields at will — a feat that may be theoretically possible, but is certainly beyond our immediate reach.
TIME TRAVEL IN SCIENCE FICTION
Time travel has long occupied a significant place in fiction. Since as early as the “Mahabharata,” an ancient Sanskrit epic poem compiled around 400 B.C., humans have dreamed of warping time, Lisa Yaszek, a professor of science fiction studies at the Georgia Institute of Technology in Atlanta, told Live Science.
Every work of time-travel fiction creates its own version of space-time, glossing over one or more scientific hurdles and paradoxes to achieve its plot requirements.
Some make a nod to research and physics, like “Interstellar,” a 2014 film directed by Christopher Nolan. In the movie, a character played by Matthew McConaughey spends a few hours on a planet orbiting a supermassive black hole, but because of time dilation, observers on Earth experience those hours as a matter of decades.
Others take a more whimsical approach, like the “Doctor Who” television series. The series features the Doctor, an extraterrestrial “Time Lord” who travels in a spaceship resembling a blue British police box. “People assume,” the Doctor explained in the show, “that time is a strict progression from cause to effect, but actually from a non-linear, non-subjective viewpoint, it’s more like a big ball of wibbly-wobbly, timey-wimey stuff.”
Long-standing franchises like the “Star Trek” movies and television series, as well as comic universes like DC and Marvel Comics revisit the idea of time travel over and over.
Here is an incomplete (and deeply subjective) list of some influential or notable works of time travel fiction:
Books about time travel:
Rip Van Winkle (Cornelius S. Van Winkle, 1819) by Washington Irving
A Christmas Carol (Chapman & Hall, 1843) by Charles Dickens
The Time Machine (William Heinemann, 1895) by H. G. Wells
A Connecticut Yankee in King Arthur’s Court (Charles L. Webster and Co., 1889) by Mark Twain
The Restaurant at the End of the Universe (Pan Books, 1980) by Douglas Adams
A Tale of Time City (Methuen, 1987) by Diana Wynn Jones
The Outlander series (Delacorte Press, 1991-present) by Diana Gabaldon
Harry Potter and the Prisoner of Azkaban (Bloomsbury/Scholastic, 1999) by J. K. Rowling
Thief of Time (Doubleday, 2001) by Terry Pratchett
The Time Traveler’s Wife (MacAdam/Cage, 2003) by Audrey Niffenegger
All You Need is Kill (Shueisha, 2004) by Hiroshi Sakurazaka
Phobos and Deimos only have two explanations, and neither one adds up.
Phobos and Deimos are the two small moons of Mars, the only rocky planet besides Earth with a moon.
Captured asteroids would not orbit in the same plane, and impact simulations cannot reproduce Phobos and Deimos.
But if an impact also created a large, innermost, third moon, maybe Mars can be explained after all.
As far as we know, there are exactly three ways that a planet can wind up possessing one or more moons.
The first way is from a circumplanetary disk, where the material that accrues around a proto-star not only fragments into planetesimals that grow and evolve but the largest protoplanets acquire their own disks of material around them, which leads to moons. This primarily applies to gas giants and is likely responsible for most of the moons in the Jovian, Saturnian, and Uranian systems.
The second way is through gravitational capture, which explains moons with bizarre orbital orientations and densities that do not match up with the parent planet’s material. This applies to moons like Saturn’s Phoebe or Neptune’s Triton, which likely both originated from the Kuiper belt.
And finally, the third way is through a major collision, which kicks up debris that coalesces into one or more natural satellites: This is the likely origin of not only Earth’s moon but all of the moons of Pluto.
And yet, when we look at all three of these methods, not a single one is capable of explaining the Martian system, with its two small, closely orbiting moons, Phobos and Deimos. On the surface, these Martian moons appear to be impossible on their own. Fortunately, when we put the other puzzle pieces together, one scenario stands out above all the rest.
When it comes to planets beyond our own solar system, we have not yet advanced to the point where current technology can unambiguously detect the presence of a moon. Direct imaging has been able to reveal the extended material around a newly forming protoplanet — surefire evidence of a circumplanetary disk that will almost certainly grow into one or more moons — but cannot yet resolve moons around mature exoplanets.
Similarly, the transit method is also limited. Sure, when an exoplanet passes in front of its parent star from our perspective, it blocks a portion of the star’s light, revealing the physical size and orbital period of the planet, once numerous transits build up. If exomoons are present, they can lead to additional flux dips superimposed atop the one caused by the planet and can also lead to transit timing variations as the orbiting moon causes the planet to move forward-and-backward in its orbit by small amounts.
Unfortunately, a non-uniformly reflective planet can exhibit a signal that is observationally indistinguishable from a planet/moon combination with superimposed flux dips. Similarly, the gravitational pull of other masses, like yet-undetected planets, can cause identical transit timing variations as exomoons.
As a result, we can only look to our own solar system for information about where moons come from. When it comes to Mars, though, none of the three methods quite fit the bill.
Why the Mars moons are “impossible”
The circumplanetary disk option only seems to apply to worlds that are massive enough to have come to dominate their orbits very early on in the history of the solar system. Only by gathering large amounts of mass in one place, early on, can a planet draw enough material into its gravitational well to lead to its own lunar system. Put simply, Mars is too low in mass to have formed with moons around it.
Gravitational capture looks tempting, especially given the superficial similarities between Phobos and Deimos and the other asteroids. However, captured bodies always wind up in randomly oriented orbits: frequently inclined and just as likely to be retrograde (opposite to the planet’s rotation) as prograde (in the same direction as its rotation). Yet Phobos and Deimos not only orbit in the same plane as one another, they orbit within ~1° of Mars’ rotational plane. If these are captured asteroids, it was an almost magical occurrence.
And yet, while that leaves the collisional origin as the third and final option, that does not work well, either. No matter what parameters are inputted into simulations — a fast or slow impactor, a massive or low mass one, a shallow or deep impact angle, etc. — there is no combination of parameters that yields two small, low-mass moons like we actually find around Mars.
When we take all of this together, it might be tempting to conclude that Mars is a mystery, and the origin of its lunar system remains obscure to us. But the more we have studied the red planet, the more circumstantial evidence we have begun to gather that simply looking at the moons that Mars possesses does not tell us the full story. In fact, the same can be said of the most familiar moon in our solar system: our own.
The origin of Earth’s moon
On Earth, for example, we did not know where the moon came from for an extremely long time. As recently as the 1980s, scientists considered that the moon might be a gravitationally captured object, despite the fact that it orbits prograde, out of the plane of Earth’s orbit around the sun by only 5°, and is tidally locked to the Earth.
However, in order to gravitationally capture a large, massive object, it has to be capable of shedding both momentum and angular momentum, requiring that something else get ejected. Unless Earth had either a rich lunar system of its own at birth — as we assume Neptune once did, leading to the capture of Triton at the expense of all its pre-existing exterior moons — or an enormous atmosphere capable of causing a tremendous amount of aerobraking, the capture scenario would be an impossibility.
Many hypotheses about the origin of Earth’s moon have been floated throughout history, but modern analyses of the material brought back from the moon during the Apollo missions have largely settled the story. The Earth and moon, as determined by analyzing the elements and isotopes that their surface rocks are made from, have identical oxygen isotope ratios, something that is different between our planet and every other planet.
Not only does this point to a common origin for the rocks found here and on the moon, but two other pieces of evidence show that the moon is almost as old as, but not quite as old as, the oldest objects in the solar system. While the most ancient asteroids have been dated to be 4.56 billion years old, we have two independent methods of estimating the age of the moon.
Lunar samples brought back from the Apollo 14 mission contained zircon fragments, which allow for an incredibly accurate form of radiometric dating to be performed: uranium-lead dating, which yields an age for the moon of 4.51 billion years.
By combining data about the thermal conductivity of the moon’s crust with the cooling properties of a hypothetical lunar magma ocean and folding in the ages and compositions of moon rocks, an age estimate of 4.43 billion years was obtained.
The Moon formed early on in the history of the solar system, but well after the completion of planetary formation. A major collision is the only explanation that fits on all counts.
An explanation for Mars’ “impossible” moons
Given that so many pieces of evidence needed to be combined to reveal the origin of our own moon, it makes sense to gather any and all potentially relevant information about Mars and its moons. Sure, our simulations pretty definitively show that no combination of collisional parameters would have produced two small moons around Mars and nothing else, but that does not rule out an impact scenario for the origin of Phobos and Deimos.
Observational sciences, like astronomy, are fundamentally different from laboratory sciences where you can perform and control your experiments however you like. In an observational science, all you get is a snapshot of what the system you are examining is like over the very brief interval you get to observe it.
For our solar system, which has been around for over 4.5 billion years, we have only a few thousand years of documented astronomical history, at most. The moons of Mars were only discovered in the late 19th century, less than 150 years ago. To claim that Mars has two moons is certainly correct, today, but we have to keep the cardinal rule of all observational sciences in mind whenever we draw conclusions. When we look at what we have, today, all we are seeing are the survivors. It is eminently possible that what exists today is just a subset of what once existed long ago.
When we look at Mars, it is easy to notice its surface features, which are numerous and varied and tell a dramatic story. Mars has a reddish color to it, evidence of widespread ferric oxide: the result of reactions taking place between iron and oxygen. The atmosphere of Mars is rich in both water vapor and carbon dioxide, both of which can oxidize iron and also combine to point toward a wet, watery history on the red planet. Its presently thin, tenuous atmosphere with what appear to be dried-up riverbeds on its surface and hematite spheres in lowland regions further indicate a watery past, with a much thicker atmosphere that must have persisted for a billion years or more.
But another spectacular feature of Mars is its heavily cratered outer layer, with dramatic highlands and lowlands. Although there are a number of prominent features like mountains, volcanoes, basins, and multiple layers of craters, perhaps the most dramatic difference can be seen between the northern and southern hemispheres of the red planet. While there are topographical variations across both hemispheres, there is an enormous basin covering half of the planet, where for some reason, roughly 50 percent of Mars is around five kilometers (three miles) lower in elevation than the rest of the planet.
How could this be possible? Even on a geologically active world like Earth, such a configuration probably never existed. Even back when the continents were all interconnected, forming Pangaea, there were likely large ridges, subduction zones, and other tremendous variations in elevation along the ocean floor, preventing the uniform, deep basin that has persisted on Mars for at least the past 3 billion years or so.
It is generally quite difficult to make a planet lopsided like this, particularly if its structure is driven by gradual, internal processes. However, there is an easy way to make a large, deep, sustaining basin: from a large impact. Not, mind you, the type of impact that created our own moon, which required a Mars-sized body striking a world nearly as large as Earth already is today. Instead, a slower collision between perhaps a Pallas-sized body (Pallas being the 3rd largest asteroid in our asteroid belt, well behind Ceres but nearly as massive as Vesta) and early Mars could have left a dramatic scar of precisely this type.
I am not attempting to suggest that a slow, massive collision kicked up debris that then created Phobos and Deimos; that is not consistent with any realistic scenario. Instead, however, it is plausible that:
an early major collision gave rise to a large debris cloud,
that cloud coalesced into not two but three moons,
where the innermost moon was largest, followed by Phobos and then Deimos,
and then the innermost moon eventually fell back onto Mars, perhaps after being tidally destroyed, creating the depressed basin we see today.
This provides a possible mechanism for explaining what remains around Mars today, while still being consistent with what is obtainable within realistic physical scenarios. When we run our simulations for the types of lunar systems that could have arisen from a giant impact on a Mars-like body back in the early stages of our solar system, a large, few-hundred-kilometer inner moon could have existed alongside Phobos and Deimos, having fallen back to Mars in an era in which only single-celled life existed on Earth. It is the one scenario that has no major conflicts with the full suite of available evidence.
Of course, there is only one way to be certain that Phobos and Deimos are made from the same materials as Mars, rather than being captured asteroids: to land on one of them and return that material to Earth. That is precisely what Japan’s Mars Moons eXploration (MMX) spacecraft is designed to do. The plan is to land on Phobos in 2024, collect material, and return it to Earth before the end of the decade, similar to what previous sample return missions have done on asteroids Itokawa and Ryugu. If Phobos is made of the same material that Mars is composed of, this will be the surefire way to find out.
For more than a century — for practically the entire duration that we have known Mars possesses moons — we have wondered about the origin of these Martian bodies. Yet the fact that we have only been around for an astronomical instant makes reconstructing the history of the solar system that much more difficult. Considering that in another few billion years, Phobos will likely fall back to Mars as well, leaving only Deimos behind, perhaps we should adopt a more positive perspective. After all, at least we have enough remaining clues today to reconstruct the cosmic story that tells us how our solar system grew up. The more time that goes by, the greater the odds that our early history gets overwritten in a way that completely erases the critical evidence we need to know the answer to perhaps the greatest question of all: where did all this come from?
This asteroid is one of the most likely to hit Earth. Here’s what it means for our future.
New ultraprecise measurements show that the asteroid Bennu has a higher chance than thought of impacting our planet sometime in the next 300 years, NASA says.
For hundreds of millions of years, a top-shaped rubble pile called Bennu has orbited the sun in relative isolation. The asteroid, about a third of a mile wide at its equator, poses no immediate threat to our planet. But hundreds of years from now, there is a small chance that Bennu could slam into Earth.
In a new study published in the scientific journal Icarus, scientists used data from NASA’s OSIRIS-REx spacecraft to make a precise calculation of Bennu’s orbit and its future proximity to our home planet. The researchers then analyzed the impact hazard between now and the year 2300. The study finds a 1-in-1,750 chance of a future collision over the next three centuries—a slightly higher probability than previously estimated.
Nearly all of the riskiest encounters with Bennu will occur in the late 2100s and early 2200s, with the single likeliest impact coming on the afternoon of September 24, 2182. On that Tuesday, Bennu has about a 1-in-2,700 chance of hitting Earth.
The team—led by Davide Farnocchia, a navigation engineer at NASA’s Jet Propulsion Laboratory—reached its revised estimate by pinpointing Bennu’s distance from Earth to within about seven feet at dozens of times between 2019 and 2020. That level of precision is like measuring the distance between the Empire State Building and the Eiffel Tower to within a few thousandths of an inch.
“Bennu is by far the best characterized asteroid in the solar system,” says University of Arizona planetary scientist Dante Lauretta, OSIRIS-REx’s principal investigator and the study’s senior author. “We know where it’s going to be over 100 years into the future, within meters. No other object in the solar system has that level of fidelity to its orbital solution—even Earth!”
University of Arizona planetary scientist Amy Mainzer, an expert on near-Earth asteroids who wasn’t involved with the study, lauded the team’s “absolutely white-glove” calculations. “If you want to be able to predict where [an asteroid] is going to go in the future, that prediction is entirely determined by how well you can measure where it is today,” she says. “This team has made an extremely precise measurement.”
Despite the slightly higher chance of impact, the risks from Bennu shouldn’t keep anyone awake at night. There’s more than a 99.9 percent chance that Bennu will not hit Earth in the next three centuries, and an impact from Bennu wouldn’t cause a mass extinction like the dino-killing Chicxulub impact 66 million years ago. That asteroid was probably about six miles across; Bennu is less than a third of a mile wide, on average.
Even so, a collision with Bennu would be regionally devastating. An impact would pack the energy of more than 1.1 billion tons of TNT, roughly two million times the energy of last year’s devastating port explosion in Beirut, Lebanon.
Ever since Bennu’s discovery in September 1999, astronomers have carefully tracked the asteroid’s orbit with ground-based telescopes, including Puerto Rico’s iconic but now lost Arecibo Observatory. These data have let astronomers predict Bennu’s future location reasonably well over the next century.
Bennu is classified as a “potentially hazardous asteroid,” meaning the object is more than 460 feet (140 meters) wide and could theoretically come within 4.65 million miles of Earth. A 2014 study found that the asteroid had roughly a 0.037 percent chance of colliding with Earth between 2175 and 2199.
But until now, simulations have run into issues beyond September 2135. Previous predictions had found that Bennu will pass within 75,000 to 330,000 miles of Earth in 2135, possibly taking the asteroid closer to Earth than the moon. Bennu has practically no chance of hitting Earth then, but depending on precisely when and where Bennu makes its close approach, our planet’s gravity could tweak the asteroid’s orbit enough to put it on a future collision course.
Computer simulations have identified the small regions of space that Bennu would have to pass through to set up a future impact. The key question is whether Bennu’s actual trajectory in 2135 will pass through any of these “keyholes,” which range from several hundred feet to a few miles wide. Answering that question requires scientists to chart Bennu’s current trajectory—and everything that could affect its future path—with unprecedented precision.
OSIRIS-REx arrived at Bennu in late 2018 as NASA’s first—and humankind’s third—attempt to sample the surface of an asteroid. The spacecraft, which snatched a dusty, pebbly sample in October 2020, is currently on its way back to Earth to drop off the precious material. But before it grabbed its sample, OSIRIS-REx spent nearly two years orbiting and studying rubble-strewn Bennu.
Because the spacecraft spent so long tagging along with the asteroid, Farnocchia and his colleagues were able to use data from OSIRIS-REx to precisely chart the asteroid’s location. Their approach had the flavor of a high-school trigonometry problem: If you know the distance from OSIRIS-REx to Bennu, and the distance from OSIRIS-REx to Earth, then you can figure out the distance between Earth and Bennu.
The team focused on periods when researchers knew OSIRIS-REx’s position relative to Bennu to within a meter (3.3 feet), based on images the spacecraft was taking of the asteroid’s surface. They then measured the timing of radio signals exchanged between OSIRIS-REx and Earth to within 15 billionths of a second.
Combining these data meant that Farnocchia’s team could calculate the distance between Earth and Bennu to within several feet, at distances ranging from 52 million to more than 201 million miles.
The team also used OSIRIS-REx data to constrain a key non-gravitational force acting on Bennu that’s known as the Yarkovsky effect. As sunlight heats up Bennu’s surface, the asteroid’s surface re-emits energy as it cools. Because Bennu rotates, the net result is a subtle thrust acting on the asteroid.
Farnocchia’s team is now able to provide a precise estimate of how the Yarkovsky effect tweaks Bennu’s orbit over time. In a NASA press briefing on August 11, Farnocchia noted that this force is equal to the weight of three grapes on Earth—and that’s enough to cause Bennu to drift by about 934 feet a year.
A swirling solar system
The new study finds that in 2135, Bennu will come within about 123,000 miles of Earth’s surface, give or take 6,000 miles, a much more precise range than previous estimates. Even though this finding rules out many previously identified keyholes, some keyholes—and future collision courses—still fall within the orbit’s margin of error. From there, the team was able to revise their estimates for Bennu’s collision risk.
The lingering uncertainty over the space rock’s future trajectory doesn’t stem from the asteroid itself, or even from OSIRIS-REx’s data. It comes from the rest of the solar system.
When Farnocchia and his colleagues ran their simulations, they had to account for many factors, including how sunlight heats up Bennu and how hundreds of other objects in the solar system, even as far away as Pluto, gravitationally tug at the asteroid. The trouble is, researchers had to estimate the masses for most of the objects within a key group: the 343 largest bodies in the asteroid belt.
“It’s amazing to me that other asteroids have any influence at all,” says Lauretta. Once other sources of error get small enough, “these effects show up, and you’re like, Wow.”
Future missions should help refine those estimates. NASA’s upcoming Near-Earth Object (NEO) Surveyor mission, scheduled to launch in 2026, is an infrared space telescope designed to look for asteroids’ heat signatures, which can be used to estimate their sizes. The telescope is expected to discover hundreds of thousands more asteroids, as well as provide better data on the asteroids that have already been found.
“You want to know as much as you can about as many of the objects out there [as you can], so that you have a reasonable idea of what’s likely to happen,” says Mainzer, the NEO Surveyor’s principal investigator.
Mainzer and Lauretta add that sending more spacecraft to more asteroids would help—and OSIRIS-REx itself is poised to get in on the action. In September 2023, the spacecraft will fly by Earth, drop a capsule full of Bennu samples into the Utah desert, and continue its journey through the solar system. So far, Lauretta’s team has found only one viable follow-on target for OSIRIS-REx: the near-Earth asteroid Apophis, which will make a close approach to Earth in April 2029.
Earth is safe from Apophis for at least the next century. But setting aside its risks to our planet, visiting worlds like Apophis will give scientists whole new vistas and terrains to explore—and a broader sense of the solar system’s history. Humankind also has more than a century to continue monitoring Bennu’s risk to Earth—and to modify that risk, if necessary. Already, space agencies are testing the procedures and technologies needed to neutralize an asteroid’s threat. In 2022, NASA’s DART spacecraft will slam into a roughly 560-foot-wide moonlet orbiting a near-Earth asteroid, with the goal of altering the moonlet’s orbit.
If humankind is threatened by an asteroid impact in the future, bigger versions of these “kinetic impactors” could be used to nudge the asteroid into a safe orbit—so long as we have at least several years’ notice before a predicted collision. For objects like Bennu, which was discovered nearly 200 years before any potential impacts, Mainzer says that humankind has “lots and lots and lots of options.”
This is why NASA classifies Asteroid 2021 NY1 as a Near-Earth Object, which they define as “an asteroid or comet that approaches our planet less than 1.3 times the distance from Earth to the Sun (the Earth-Sun distance is about 93 million miles).”
Asteroid 2021 NY1 is also considered to be a Potentially Hazardous Object by NASA, “because the gravitational tug of the planets could, over time, cause an object’s orbital path to evolve into an Earth-crossing orbit. This allows for the possibility of a future collision.”
According to SpaceReference.org, “2021 NY1 orbits the sun every 1,400 days (3.83 years), coming as close as 0.99 AU and reaching as far as 3.90 AU from the sun.”
So it’s all good, right? Sure. If you believe NASA, who never tries to conceal the truth and never keeps anything hidden from the American public.
A ‘blue bang’ sparks an unusual type of lightning in the upper atmosphere
Scientists have finally gotten a clear view of the spark that sets off an exotic type of lightning called a blue jet.
Blue jets zip upward from thunderclouds into the stratosphere, reaching altitudes up to about 50 kilometers in less than a second. Whereas ordinary lightning excites a medley of gases in the lower atmosphere to glow white, blue jets excite mostly stratospheric nitrogen to create their signature blue hue.
Blue jets have been observed from the ground and aircraft for years, but it’s hard to tell how they form without getting high above the clouds. Now, instruments on the International Space Station have spotted a blue jet emerge from an extremely brief, bright burst of electricity near the top of a thundercloud, researchers report online January 20 in Nature.
Understanding blue jets and other upper-atmosphere phenomena related to thunderstorms, such as sprites (SN: 6/14/02) and elves (SN: 12/23/95), is important because these events can affect how radio waves travel through the air — potentially impacting communication technologies, says Penn State space physicist Victor Pasko, who was not involved in the work.
Cameras and light-sensing instruments called photometers on the space station observed the blue jet in a storm over the Pacific Ocean, near the island of Nauru, in February 2019. “The whole thing starts with what I think of as a blue bang,” says Torsten Neubert, an atmospheric physicist at the Technical University of Denmark in Kongens Lyngby. That “blue bang” was a 10-microsecond flash of bright blue light near the top of the cloud, about 16 kilometers high. From that flashpoint, a blue jet shot up into the stratosphere, climbing as high as about 52 kilometers over several hundred milliseconds.
The spark that generated the blue jet may have been a special kind of short-range electric discharge inside the thundercloud, Neubert says. Normal lightning bolts are formed by discharges between oppositely charged regions of a cloud — or a cloud and the ground — many kilometers apart. But turbulent mixing high in a cloud may bring oppositely charged regions within about a kilometer of each other, creating very short but powerful bursts of electric current, Neubert says. Researchers have seen evidence of such high-energy, short-range discharges in pulses of radio waves from thunderstorms detected by ground-based antennas.
Five reasons why sorting all of this out is so scientifically challenging
Just before the release in June of the much-anticipated Pentagon report on unidentified aerial phenomena (UAP), I sat down to try to create a list of the greatest hurdles to UAPs’ scientific analysis. What I came up with were five major challenges that are described here, together with a cross-comparison with some of the statements made in the published government report. Although only nine pages long, that report turns out to be thorough, careful and scientifically accurate in that it fully expresses how little certainty can be drawn from the data to hand. As the saying goes: the more things change, the more they stay the same.
Challenge No. 1: All UAP/UFO incidents are nonrepeatable: we can’t go back and perform the “experiment” of that exact observation again.
For science in general, this kind of thing is a big headache. A lack of repeatability or replication poses a very significant challenge for the interpretation of data (especially if those data are noisy and incomplete); for filling in obvious gaps; and for eliminating or supporting any hypotheses. As the Pentagon report states: “Limited data leaves most UAP unexplained….” Limited, anecdotal and nonrepeatable are hardly the words you want to use, but they apply here.
Challenge No. 2: There is nothing systematic in how incidents are recorded or reported. Different camera systems, radar systems, data processing, observers and environmental circumstances mean that each incident is, in effect, an uncontrolled experiment, with few ways to ascertain the real quality and sensitivity of data.
Again, the Pentagon report states effectively the same point: “The limited amount of high-quality reporting on unidentified aerial phenomena (UAP) hampers our ability to draw firm conclusions about the nature or intent of UAP.” The report then goes on to suggest a potentially useful task of: “Consistent consolidation of reports from across the federal government, standardized reporting, increased collection and analysis, and a streamlined process for screening.”
This is really important; the report is very, very specific about the lack of appropriateness of typical military sensor equipment for this sort of analysis. “The sensors mounted on U.S. military platforms are typically designed to fulfill specific missions. As a result, those sensors are not generally suited for identifying UAP.”
Challenge No. 3: There is no easy way to account for “cherry-picking” of data. We don’t know how often pilots or other observers see something unexpected but then, a minute later, figure out what they’re witnessing (or at least convince themselves they’ve done so) and consequently don’t report anything. There could be thousands of such incidents, or very few. We don’t know, and those “mundane” cases could actually represent all cases.
The report does discuss the “stigma” surrounding personnel or observers reporting UAPs, but it also states that out of the 144 reports that were studied, only 18 incidents (covered in 21 of the reports) appeared to demonstrate “advanced technology,” inasmuch as there was an appearance of unusual aeronautical behavior in movement.ADVERTISEMENT
In a small (unspecified) number of cases there was even evidence of military aircraft systems “processing radio frequency (RF) energy”—whatever that really means; presumably there was some increased radio noise. But, as for all the times that nothing was reported, either because something was quickly identified, or a pilot just chose not to, that remains a total unknown.
Challenge No. 4: If any incidents or observations are genuinely associated with something tangible and physical, we don’t know whether we’re looking at a single underlying phenomenon or many. It’s a bit like going into a zoo blindfolded and trying to understand what you’re hearing and smelling. If there’s only one species you might figure it out, but if there are 100 species, then decoding your experience is going to be very difficult.
Again, the report hits this nail right on the head, with an entire section titled “UAP probably lack a single explanation.” Some of the possibilities offered are: “Airborne clutter … birds, balloons, recreational unmanned aerial vehicles … debris like plastic bags … that muddle a scene,” as well as natural atmospheric phenomena (ice crystals, thermal fluctuations that can register on infrared and radar systems), classified aircraft and the like, and foreign “adversary systems.”
The Pentagon report also provides an outline of ongoing efforts, and possible future directions, for trying to improve all analyses. This includes a more systematic collection of military aircraft sensor data, along with FAA data, and applying machine learning to sift through current and historical information to look for “clusters,” patterns and associations with known phenomena like weather balloons, wildlife movements and other Earth-monitoring databases.
Challenge No. 5: The popular association of UAP with hypotheses involving alien technology creates a severe analysis bias. Usually, science tries to move stepwise towards finding support for a given hypothesis or for eliminating hypotheses, and weighs those options as evenly as possible. But in this case a hypothesis that would require extraordinarily robust evidence in order to be supported (as with Carl Sagan’s famous dictum “Extraordinary claims require extraordinary evidence”), regardless of what some people say, hangs heavily over any analysis or discussion, and there is a vocal community who feel that the answer is already known. That’s a problem.
In fact, and rather ironically, the “sociocultural stigmas” around recording surprising observations mentioned in the report are undoubtedly exacerbated by elements of the UFO community that express ideas or beliefs that are, well, fantastical in nature.
Consequently, observers such as highly trained, professional pilots are likely going to be reticent to mention things they are very surprised by. This relates to point No. 3 and creates bias because the unreported incidents, if further analyzed, could provide significant insight—especially as to how often human observers are simply confused, as opposed to witnessing genuinely unusual phenomena.
Where does all of this leave us? Well, the Pentagon report does suggest ways to improve data collection and analysis, as I’ve described. It also points out that if some UAP do represent physical hazards, or security challenges, it would be important to figure that out. In that sense, there is some possible risk mitigation to be had by investigating UAP further, irrespective of an eventually mundane or extraordinary explanation.
As a scientist who studies the possibilities of life elsewhere in the cosmos, I find myself saying “Well, it seems worth having some more work done on this.” But that’s not because I think it’s likely that extraterrestrials or their probes could be dropping into Earth’s atmosphere. Although as a rational thinker I can’t, and shouldn’t, permanently exclude such possibilities, my point No. 5 bothers me enough that I’d rather follow the stepwise approach. There are other benefits to that strategy too.
New kinds of high-resolution time-lapse data and high-fidelity monitoring of our planetary environment could have many additional benefits as we try to navigate our way through a perilously changing world. From atmospherics to animal migration to human-generated garbage floating in the air and on the sea, seeing what’s actually going on is always going to help.
The Search for Extraterrestrial Intelligence (SETI) has been growing in confidence and repute lately thanks to astronomer’s detections of habitable worlds and the private funding been poured into the enterprise. With renewed efforts afoot, it’s worth pausing for a moment and asking – well what do we do if we succeed? How should the scientists communicate their results? How will the public react? Social media in particular disrupts the conventional pattern of scientific announcements and poses some interesting challenges for SETI. In this video we perhaps end up asking more questions than answers, but let’s get into a discussion in the comments about how best to proceed!
In the age of fake news, researchers worry conspiracy theories would abound before we could figure out how — or if — to reply to an alien message.
The answer to this question could affectall of our lives more than nearly any other policy decision out there: How, if it all, should humanity respond if we get a message from an alien civilization?
And yet politicians and scientists have never bothered to get our input on it.
At long last, that’s changing. A group of researchers in the UK this week released the first major survey on the question. The responses could help inform an international protocol for responding to first contact.
This is a big deal because, as Stephen Hawking and Elon Musk have warned, communicating with extraterrestrials could pose a catastrophic risk to humanity. In fact, if we send out a message and it’s received by less-than-friendly aliens, that could pose an existential threat not only to the human species but to every species on Earth.
Despite the high stakes, scientists have already sent out signals intended to be picked up by aliens. The first one went out in 1974, when the Arecibo radio telescope in Puerto Ricotransmitted a broadcast containing information on everything from the position of Earth in our solar system to the double helix structure of DNA.
The Arecibo Observatory is currently running a contest that invites kids to design our next message to E.T. And later this year, an organization called Messaging Extraterrestrial Intelligence (METI) plans to transmit a new message containing information on the periodic table. There’s no law saying they can’t, or even that they need to get some international buy-in.
But the scientists at the UK SETI Research Network (UKSRN) think we’re woefully unprepared to handle an alien message if we receive one. And they say no one class of people should unilaterally decide humanity’s response. As astronomer Martin Dominik put it, “We want to hear people’s views. The consequences affect more people than just scientists.”
1) Some people think we should send messages into space even if we don’t receive a message first. What is your opinion?
2) If we receive a message, do you think we should reply/make contact or not? Why?
3) What would you consider a credible source?
That third question reflects a worry I’ve been hearing from astronomers over the past couple of years: If a newly discovered message from aliens is announced, members of the public may use social media to spread all sorts of fake news and conspiracy theories about the aliens, their message, and what it will mean for humanity to communicate with them. In the weeks or months or years it could take scientists to decode the interstellar missive, fear-mongering could tank our chances of responding wisely — or at all.
An alien message “will take time to understand and if that work starts to drag out and there is nothing new we can say, the information vacuum will be filled with speculation,” John Elliott, a UKSRN co-founder, told the Guardian. “Conjecture and rumor will take over.”
In hopes of figuring out how to minimize the problem, the survey asks which information sources you’d trust: Main news channels? Direct quotes from scientists? Official government statements? Other sources?
It also asks if you’d post on social media about the discovery of an alien message. If so, would you restrict yourself to defending the scientific evidence? Or would you maybe engage in speculation? Would the absence of any news on the signal’s decoding encourage you to speculate?
You can see how it’d be useful to scientists to be able to predict the public’s response in these scenarios. But there’s a difference between how I say I’d react when I’m filling out a questionnaire, and how I’d actually react in real life. In addition to that limitation, the UKSRN survey is weakened by the fact that the same person can take it more than once from different devices.
Still, it’s an improvement over the lack of public consultation we’ve seen on these questions in the past.
Who gets to make rules about what happens in space?
For decades, the international community has been exploring the possibility of establishing a mechanism for global oversight when it comes to our engagement with outer space. But even if everyone were to agree that’s a good idea, the question of how to set it up and make it enforceable is incredibly complicated.
The 1967 Outer Space Treaty was an early effort in this vein. Ratified by dozens of countries and adopted by the United Nations against the backdrop of the Cold War, it laid out a framework for international space law. Among other things, it stipulated that the moon and other celestial bodies can only be used for peaceful purposes, and that states can’t store their nuclear weapons in space. The treaty suited its historical context, but it didn’t tackle the concerns people have nowadays about messaging an alien intelligence.
Another inflection point came in the late 1980s, when scientists with the organization Search for Extraterrestrial Intelligence (SETI) drafted a post-detection protocol, a list of best practices for what to do if and when we ever find aliens. One of its principles reads: “No response to a signal or other evidence of extraterrestrial intelligence should be sent until appropriate international consultations have taken place.”
This protocol was put on file as a brief with the Outer Space Treaty at the UN, and it was endorsed by the International Academy of Astronautics and the International Institute for Space Law. But it has no regulatory force when it comes to those who actively send out messages à la METI.
In 2015, SETI researchers, Musk, and others released a statement criticizing METI efforts. “We feel the decision whether or not to transmit must be based upon a worldwide consensus, and not a decision based upon the wishes of a few individuals with access to powerful communications equipment,” it said. “We strongly encourage vigorous international debate by a broadly representative body prior to engaging further in this activity.”
So far, though, there is still no “broadly representative body” regulating what messages can be sent into space or by whom.
Alessandra Abe Pacini, a researcher at Arecibo who helped generate the idea for the kids’ contest, told me the question of whether any message should be transmitted at all is “very controversial,” adding: “Even here among the scientists at Arecibo, there is no consensus.”
If some of the smartest astronomers in the worldcan’t come to an in-house agreement, is there any hope that the international community will ever agree? Maybe not, but the UKSRN survey may at least help us find out how much consensus there is or isn’t among the public. That’s a good first step.
The SpaceX mission seeks to raise some $200 million dollars for St. Jude Children’s Research Hospital.
Inspiration4 / John Kraus
Last night at 8:02 PM EDT, the crew of Inspiration 4 — the first all-civilian spaceflight — blasted off from historic Launch Complex 39A at NASA’s Kennedy Space Center. Tucked inside a SpaceX Crew Dragon capsule, which was lofted to orbit atop a SpaceX Falcon 9 rocket, are four fortunate astronauts: Sian Proctor, Hayley Arceneaux, Christopher Sembroski, and Jared Isaacman. The latter footed the bill for the trip.
Unlike the recent suborbital spaceflights of billionaires carried out this summer by Blue Origin and Virgin Galactic, Inspiration4 is setting its sights higher, taking the untrained civilian crew all the way to orbit. There, they will circle the Earth for three days, conducting experiments and enjoying their views before returning for a soft water landing off the coast of Florida.
Although Inspiration4 is currently orbiting more than 100 miles above the International Space Station (ISS), one of the mission’s main goals is much more Earth-bound: to raise awareness and funding for St. Jude Children’s Research Hospital. At St. Jude, children receive treatment for cancer and other life-threatening diseases. And perhaps most importantly, families treated at the hospital never receive a bill. The mission hopes to raise $200 million for St. Jude.
Commanding the Inspiration4 mission is Isaacman, founder and Chief Executive Officer of Shift4 Payments. The American billionaire is also a pilot. Proctor earned her seat by winning a contest hosted by Shift4.
Similarly, Sembroski got his seat from a contest, but not one that he won. Instead, his friend won the seat in a charity raffle for St. Jude and, for personal reasons, declined the seat, instead offering it to Sembroski.
Inspiration4 crew before liftoff. Inspiration4 / John Kraus
Arceneaux was a childhood cancer survivor and former patient at St. Jude who now works at the hospital as a physician’s assistant. She will become the youngest American (and the first person with a prosthetic body part) to venture to space. Arceneaux was personally selected by Isaacman to be on the flight.
Also on board are numerous items that will later be auctioned off for St. Jude, including the first minted non-fungible token (NFT) to be played in orbit. Other items include mission jackets decorated with artwork from St. Jude patients, 66 pounds of hops from Samuel Adams that can be used to create out-of-this-world beer, a to-be-autographed copy of Time with the crew on the cover, and much more.about:blankabout:blank
Inspiration4 / John Kraus
Breaking records left and right
The launch last night went off without a hitch, and it was celebrated with fist bumps by the crew, even as they were still climbing to their final orbital altitude.
Their excitement, however, is warranted. Besides becoming the first all-civilian mission, Inspiration4 will also be the first orbital human space mission to not dock at the ISS since the final Hubble mission in 2009.
At an orbit of 363 miles (585 kilometers), Inspiration4 is now above both the ISS and the Hubble Space Telescope. In fact, the Inspiration4 crew is currently farther from Earth than any humans have been since the Apollo missions.
One more record Inspiration4 launch helped break: the greatest number of people in space at one time. NASA’s Expedition 65 mission currently has a crew of seven people aboard the ISS, while China’s Shenzhou-12 mission includes three astronauts who are concluding a 90-day trip with their return to Earth tomorrow. So for a few brief days, the four civilians of the Inspiration4 crew brings the total space population up to 14, just edging out the previous record of 13 set in 2009.
The Juno spacecraft has gotten a private radio show from Jupiter’s closest moon, the highly volcanic Io.
NASA’sJuno spacecraft is “listening” in on radio emissions from Jupiter’s volcanic moon Io, allowing researchers to discover what triggers the strange radio waves.
Of all the planets in our solar system, Jupiter has the largest and most powerful magnetic field, which extends so far that some of the planet’s moons orbit within it. Because Io is closest to the planet, the moon is “caught in a gravitational tug-of-war” between Jupiter and two other large moons, according to NASA. These opposing pulls cause massive internal heat, which has led to hundreds of volcanic eruptions across the moon’s surface.
The volcanos release 1 ton of gasses and particles per second into space, NASA said in a statement. Some of this material splits into electrically charged ions and electrons that then rain down onto Jupiter through the planet’s magnetic field. Electrons caught in the magnetic field are accelerated toward Jupiter’s poles and, along the way, generate a phenomenon scientists call decameter radio waves (also known as decametric radio emissions, or DAM).
When the spacecraft is in the right spot to listen, Juno’s Waves instrument can pick up these radio waves, Yasmina Martos of NASA’s Goddard Space Flight Center said in the statement. Researchers have used data from Juno to pinpoint where in Jupiter’s massive magnetic field the radio emissions come from. The data sheds light on the behavior of the enormous magnetic fields gas giants create.
According to the research team, the radio waves come from space that can be described as a hollow cone, where the conditions are just right: the right magnetic field strength and the right density of electrons. The signal rotates like a lighthouse and Juno picks it up only when the “light” is shining on the spacecraft, according to the NASA statement.
The radio data also showed that the electrons that create these radio waves emit a massive amount of energy, 23 times greater than researchers expected. Such electrons can come from other sources, too, such as from the planet’s magnetic field or from a solar wind, according to the research team.
With humans likely the threat, Tokyo needs to lend its eyes on the sky
People look at the night sky using night vision goggles during an UFO tour in the desert outside Sedona in the U.S. state of Arizona.
TOKYO — Gone are the days when UFO stories were dismissed as crackpot pseudoscience. Today, they are an emerging field of public policy debate.
A recent U.S. report on unidentified flying objects, or what the intelligence community calls unidentified aerial phenomena (UAP), has brought these mysterious sightings into the realm of serious discussion on national security.
The world’s powers need to take note. Japan and European allies of the U.S. should work on sharing information on UAP to learn more about them and assess potential security risks.
The report released on June 25 by the Office of the Director of National Intelligence examines 144 incidents of UAP gathered since 2004, mainly by the U.S. military. Most of them are from the past two years.
For many readers, the nine-page document raised more questions than it answered. Of the 144 reported UAP sightings, the Pentagon task force that examined the episodes could offer a reasonable explanation for only one case, identified as “a large, deflating balloon.” The rest remain unexplained.
In 18 incidents, unusual UAP movement patterns or flight characteristics were observed. “Some UAP appeared to remain stationary in winds aloft, move against the wind, maneuver abruptly, or move at considerable speed, without discernible means of propulsion,” according to the report. There are also 11 reports of near misses between the observing aircraft and a UAP.
The report is based on the work of the Department of Defense’s Unidentified Aerial Phenomena Task Force, set up in August 2020 in response to a flurry of UAP sightings in recent years. At a glance, the document seems to be a feast for UFO believers and conspiracy theorists. But far from being that, it reflects the growing interest in these phenomena among U.S. policymakers.ADVERTISING
After the release of the report, some U.S. lawmakers and security experts called for redoubled efforts to determine the truth behind UAP. “The United States must be able to understand and mitigate threats” posed by UAP, said Sen. Mark Warner, a Democrat from Virginia who serves as chairman of the Senate Select Committee on Intelligence.
Republican Sen. Marco Rubio of Florida concurred, saying, “The Defense Department and intelligence community have a lot of work to do before we can actually understand whether these aerial threats present a serious national security concern.”
The Pentagon is willing to respond to such calls. In late June, Deputy Secretary of Defense Kathleen Hicks directed the Office of the Under Secretary of Defense for Intelligence and Security to develop a plan to formalize the UAP task force’s activities.
A U.S. security expert with knowledge of discussions on this topic in the Biden administration said civilian and military officials are primarily worried that some aerial sightings may be linked to foreign countries or groups hostile to the U.S.
This is a more palpable threat than invading aliens. Even if intelligent life exists elsewhere in the vast universe, the sheer distances involved make it unlikely that such beings are visiting Earth at anywhere near the pace of reported UAP sightings.
Professor Hitoshi Murayama, a well-known theoretical particle physicist teaching at the University of California, Berkley, explained.
“Any planet with an environment similar to that of Earth is thought to be at least about four light years away from us,” Murayama said.
“Shuttling between such a planet and Earth would take an incredibly long time even with extremely sophisticated technology,” he said. “If extraterrestrial visitors are involved [in any of the UAP], it is hard to understand how they travel to the Earth so frequently.”
Existing earthly spaceships would take about 30,000 years to travel to a planet four light years away. Even for civilizations with far more advanced technology, the distance would be a daunting hurdle. These scientific assumptions support the view that UAP are human in origin. If so, at least some of the sightings may involve unknown highly advanced technology from countries like Russia or China, possibly representing a serious security threat to the U.S.
Multiple military experts warn that objects capable of the otherworldly flight characteristics reported in some UAP were used for military purposes, intercepting or tracking them with existing weapons systems would be next to impossible. Some UAP reports by the U.S. forces exhibit high-level stealth capabilities that defy radar detection.
The report mentions the possibility of “technologies deployed by China, Russia, another nation, or a nongovernmental entity.” But it admits there is no solid evidence to support such claims.
The report also suggests some UAP observations could be attributable to classified programs undertaken by the U.S. government or industry. If this is the case, however, such programs have been going on without the knowledge of top U.S. intelligence and defense officials.
The report does not necessarily rule out the involvement of alien visitors. Christopher Mellon, former deputy assistant secretary of defense for intelligence during the Clinton and George W. Bush administrations, argued for taking the alien theory seriously in a blog post on the UAP report.
“In my view, the UAP report’s findings strengthen the case for the alien hypothesis by undermining the main alternatives and providing examples of capabilities we cannot emulate or even understand,” Mellon said.
The topic should also raise security red flags for Japan and other U.S. allies that depend on the American military for their defense. Any technology unknown to the U.S. that defies responses by its military, whether human or extraterrestrial in origin, could pose a serious potential threat.
Closer cooperation between the U.S. and its allies on sharing and studying UAP sightings is essential. Most of the 144 UAP episodes covered by the report occurred in or around U.S. airspace.
If a foreign state or group is developing advanced weapons, chances are it will conduct more tests in other parts of the world rather than risk exposing its work to the Americans. If Russia or China were involved, Japan might be in a better geographical position than the U.S. to gather information about the technology.
Japan is beginning to take a minimum response to the challenge. Last September, one month after the U.S. set up the UAP task force, then Defense Secretary Taro Kono issued an unusual order to the Self-Defense Forces to take visual records and analyze such sightings.
During his meeting last summer with then-U.S. Defense Secretary Mark Esper, Kono raised the topic and agreed with the Pentagon chief to share information.
Traveling to space has become a thing among the world’s multibillionaires. This month, Virgin Group founder Richard Branson rode into space aboard a rocket he helped fund, followed less than two weeks later by Amazon.com founder Jeff Bezos.
But humans know only a sliver of the vast universe. While lawmakers and news media should still never feed wild alien conspiracy theories, the U.S. report has spelled the end of the taboo on discussing UFOs in the public policy sphere.
Astronomers have obtained the sharpest and most detailed images yet of the asteroid Kleopatra. The observations have allowed the team to constrain the 3D shape and mass of this peculiar asteroid, which resembles a dog bone, to a higher accuracy than ever before. Their research provides clues as to how this asteroid and the two moons that orbit it formed.
Using the European Southern Observatory’s Very Large Telescope (ESO’s VLT), a team of astronomers have obtained the sharpest and most detailed images yet of the asteroid Kleopatra. The observations have allowed the team to constrain the 3D shape and mass of this peculiar asteroid, which resembles a dog bone, to a higher accuracy than ever before. Their research provides clues as to how this asteroid and the two moons that orbit it formed.
“Kleopatra is truly a unique body in our Solar System,” says Franck Marchis, an astronomer at the SETI Institute in Mountain View, USA and at the Laboratoire d’Astrophysique de Marseille, France, who led a study on the asteroid — which has moons and an unusual shape — published today in Astronomy & Astrophysics. “Science makes a lot of progress thanks to the study of weird outliers. I think Kleopatra is one of those and understanding this complex, multiple asteroid system can help us learn more about our Solar System.”
Kleopatra orbits the Sun in the Asteroid Belt between Mars and Jupiter. Astronomers have called it a “dog-bone asteroid” ever since radar observations around 20 years ago revealed it has two lobes connected by a thick “neck.” In 2008, Marchis and his colleagues discovered that Kleopatra is orbited by two moons, named AlexHelios and CleoSelene, after the Egyptian queen’s children.advertisementMotegrity® (Prucalopride) – Official Physician SiteSee Motegrity Dosing and Administration Information at the Official Physician Site.www.motegrityhcp.com
To find out more about Kleopatra, Marchis and his team used snapshots of the asteroid taken at different times between 2017 and 2019 with the Spectro-Polarimetric High-contrast Exoplanet REsearch (SPHERE) instrument on ESO’s VLT. As the asteroid was rotating, they were able to view it from different angles and to create the most accurate 3D models of its shape to date. They constrained the asteroid’s dog-bone shape and its volume, finding one of the lobes to be larger than the other, and determined the length of the asteroid to be about 270 kilometres or about half the length of the English Channel.
In a second study, also published in Astronomy & Astrophysics and led by Miroslav Brož of Charles University in Prague, Czech Republic, the team reported how they used the SPHERE observations to find the correct orbits of Kleopatra’s two moons. Previous studies had estimated the orbits, but the new observations with ESO’s VLT showed that the moons were not where the older data predicted them to be.
“This had to be resolved,” says Brož. “Because if the moons’ orbits were wrong, everything was wrong, including the mass of Kleopatra.” Thanks to the new observations and sophisticated modelling, the team managed to precisely describe how Kleopatra’s gravity influences the moons’ movements and to determine the complex orbits of AlexHelios and CleoSelene. This allowed them to calculate the asteroid’s mass, finding it to be 35% lower than previous estimates.
Combining the new estimates for volume and mass, astronomers were able to calculate a new value for the density of the asteroid, which, at less than half the density of iron, turned out to be lower than previously thought . The low density of Kleopatra, which is believed to have a metallic composition, suggests that it has a porous structure and could be little more than a “pile of rubble.” This means it likely formed when material reaccumulated following a giant impact.
Kleopatra’s rubble-pile structure and the way it rotates also give indications as to how its two moons could have formed. The asteroid rotates almost at a critical speed, the speed above which it would start to fall apart, and even small impacts may lift pebbles off its surface. Marchis and his team believe that those pebbles could subsequently have formed AlexHelios and CleoSelene, meaning that Kleopatra has truly birthed its own moons.
The new images of Kleopatra and the insights they provide are only possible thanks to one of the advanced adaptive optics systems in use on ESO’s VLT, which is located in the Atacama Desert in Chile. Adaptive optics help to correct for distortions caused by the Earth’s atmosphere which cause objects to appear blurred — the same effect that causes stars viewed from Earth to twinkle. Thanks to such corrections, SPHERE was able to image Kleopatra — located 200 million kilometres away from Earth at its closest — even though its apparent size on the sky is equivalent to that of a golf ball about 40 kilometres away.
ESO’s upcoming Extremely Large Telescope (ELT), with its advanced adaptive optics systems, will be ideal for imaging distant asteroids such as Kleopatra. “I can’t wait to point the ELT at Kleopatra, to see if there are more moons and refine their orbits to detect small changes,” adds Marchis.
We have been broadcasting for over 100 years. Now a new 3D map of the galaxy reveals the stars these signals have reached that can also see Earth.
When Guglielmo Marconi made the first “long-distance” radio broadcasts in 1895, his assistant tuned into from a less than a kilometer away. Marconi went on to develop the world’s first commercial radio system and, by the time of his death in 1937, radio signals were routinely used to communicate across the world.
These broadcasts have also travelled into space, signaling to all who care to tune in, that humanity has emerged as a technologically advanced species. The first signals have now been travelling for over hundred years, reaching distances that would have been unimaginable to Marconi.
That raises some interesting questions about the stars these signals have already reached. What kind of stars are they, do they host exoplanets and if so, are any potentially Earth-like and in the habitable zone? How many of these exoplanets might also be able to see us?about:blankabout:blank
Now we get an answer thanks to the work of Lisa Kaltenegger at Cornell University in Ithaca and Jackie Faherty at the American Museum of Natural History in New York City. These astronomers have calculated the size of the sphere that our radio signals have covered since they left Earth, counted the stars that sit inside it and worked out which of them should also be able to see Earth transiting the Sun.
3D Star Map
All this is made possible by the Gaia Catalogue, a new 3D map of our galaxy showing the distance and motion of more than 100 million stars. The data comes from the European Space Agency’s Gaia spacecraft that was launched in 2013 and is mapping the position and motion of some 1 billion astronomical objects.
The resulting map is giving astronomers an entirely new way to study our galactic environment. Kaltenegger and Faherty’s project is a good example. Since Gaia measures how these stars are moving relative to one another, the researchers can work out for how long we have been visible to them and for how much longer.
Kaltenegger and Faherty say 75 stars systems that can see us, or soon will, sit within this 100 light year sphere. Astronomers have already observed exoplanets orbiting four of them.
These systems are generally well studied. The researchers say, for example, that the Ross128 star system is the 13th closest to the Sun and the second closest with a transiting Earth-size exoplanet. Then there is Teegarden’s Star, with at least two Earth-mass exoplanets and the Trappist-1 star system with seven Earth-sized planets, of which four are in the habitable zone.about:blankabout:blank
Our signals continue to radiate away from us. So Kaltenegger and Faherty also pick out at the star systems set to receive our signals in the next 200 years or so and will also be able to see us. “1,715 stars within 326 light-years are in the right position to have spotted life on a transiting Earth since early human civilization, with an additional 319 stars entering this special vantage point in the next 5,000 years,” they say.
Exoplanet statistics suggest that at least 25 per cent of these stars will have rocky exoplanets. So there should be at least 508 rocky planets in this population with a good view of earth. “Restricting the selection to the distance radio waves from Earth have traveled- about 100 light-years – leads to an estimated 29 potentially habitable worlds that could have seen Earth transit and also detect radio waves from our planet,” say Kaltenegger and Faherty.
Of course, the possibility of life on these worlds is entirely unknown. The next generation of space telescopes should allow astronomers to study these worlds in more detail, to determine their atmospheric make up and perhaps see continents and oceans.
To similarly equipped alien eyes, Earth will have long looked an interesting target. Life first emerged here some 4 billion years ago, ultimately giving our atmosphere its rich oxygen content and its other biomarkers, such as methane. If astronomers find similar conditions elsewhere, that will pique their interest.
It could even prompt searches for radio signals that may already be reaching us from these places. Marconi would surely have been amazed.
Astronomy is a bit different from many sciences because you only have a sample size of 1. The cosmos contains everything we can observe, so astronomers can’t study multiple universes to see how our universe ticks. But they can create computer simulations of our universe. By tweaking different aspects of their simulation, astronomers can see how things such as dark matter and dark energy play a role in our universe. Now, if you are willing to spring for a fancy hard drive, you can keep one of these simulations in your pocket.
The Uchuu simulation is the largest and most detailed simulation of the universe ever made. It contains 2.1 trillion “particles” in a space 9.6 billion light-years across. The simulation models the evolution of the universe across more than 13 billion years. It doesn’t focus on the formation of stars and planets but instead looks at the behavior of dark matter within an expanding universe. The detail of Uchuu is high enough that the team can identify everything from galaxy clusters to the dark matter halos of individual galaxies. Since dark matter makes up most of the matter in the universe, it is the main driver of galaxy formation and clustering.
It takes a tremendous amount of computational power and storage to create such a detailed model. The team used over 40,000 computer cores and 20 million computer hours to generate their simulation, and it produced more than 3 Petabytes of data. That’s 3,000 Terabytes or 3 million Gigabytes for us mortals. Using high-density compression, however, the team was able to compress their results into a mere 100 Terabytes of storage.
That’s still a tremendous amount of data, but it can be stored on a single drive. For example, the Exadrive from Nimbus is a 100 Tb solid-state drive in a standard 3.5-inch form factor. Granted, it will set you back $40,000, but if you have that kind of change hiding between your couch cushions, why not use it to keep a universe in your pocket. Fortunately, if you don’t have that much spare change, you can access the data online. The Uchuu team has their raw data on skiesanduniverses.org, so you can explore their virtual universe all you want.
In addition to being a detailed cosmic simulation, the Uchuu simulation can be used by researchers working on scientific data mining. As large sky surveys and more simulations are created, the data will become so large data mining will play a crucial role in astronomical research. Until that data becomes available, data miners can hone their skills on a pocket universe.
NASA’s Goldstone 70-meter (230 foot) antenna captured radar imagery of asteroid 2016 AJ193 on Aug. 22, 2021 as it passed about 2.1 million miles (about 3.4 million kilometers) away from Earth.
A gigantic asteroid that is considered potentially hazardous by NASA zipped past the Earth at a very high rate of speed. The asteroid, called 2016 AJ193, flew past the Earth at a velocity of 58,000 mph. It’s hard to imagine a speed that high; it equates to traveling about 16 miles every second.
NASA estimates the asteroid is about 4800 feet wide, approximately four times as wide as the Empire State building is tall. The asteroid passes through the solar system every six years on its orbit around the sun. Scientists are taking advantage of its proximity to the Earth on this orbit to study it in detail.
Astronomers observed the asteroid using radar, which is similar to the tech used for tracking thunderstorms on Earth. 2016 AJ193 Is a medium-size Apollo class asteroid. NASA says it’s comparable in size to the Pentagon. At its closest approach to Earth, it passed within 3,427,445 kilometers.
Anyone can tell that it was very far from our planet, but that is considered a close flyby on the astronomical scale of things. The asteroid has an elliptical orbit around the sun, and at its closest point, it’s 0.60 AU from the Sun, and at the furthest point of its orbit is 5.93 AU. An astronomical unit (AU) is the distance the Earth orbits from the sun.
The close approach that happened yesterday was one of only two coming in the near future. 2016 AJ193 will make its next near pass to the earth on August 19, 2080, when it will be 6,999,373 kilometers from Earth. It will have slowed down from its current velocity of 26.169 km/s to 21.713 km/s on that orbit.
NASA is a sprawling organization that has to talk to everything from politicians in Washington DC to space probes that have left the solar system. Discussions with the first might be as simple as a written letter for informal conversation, while the second requires a high-power network of ground-based antennas. Known as the Deep Space Network (DSN) this series of antennas spread over three continents is the backbone of NASA’s communications with its various space probes. Now the DSN is in the process of implementing a well-deserved upgrade.
Part of the reason for that upgrade is the sheer number of spacecraft in deep space NASA has to communicate with. Everything from Voyager to the Parker Solar Probe requires time on the antenna to relay data and receive instructions. But with new missions launching at an increasing pace, the network must be beefed up in order to accommodate all the new communication links.
Currently, DSN supports 39 missions, but NASA has 30 additional missions in development, and not all of the existing missions will be phased out in the near future. To ensure consistent communication no matter where the Earth is on its journey around the sun, the antennas supporting those 30 missions are evenly spread around the globe – in Madrid, Spain, Canberra, Australia, and near Barstow California. When not being used for communication directly, the antennas can serve as data collection platforms for radio science missions as well.
One major component of the upgrade needed to support all this work is the addition of 2 new antennas. The first, a 34-m wide dish named DSS-56 was commissioned in Madrid in January of this year. Also completed this year was an upgrade to DSS-43, a 70-m antenna located in Australia that is the only antenna in the Southern Hemisphere that is capable of sending messages to Voyager, which is currently outside of our solar system.
DSS-43 won’t be the last 70-m antenna improvement either – its equivalents in Madrid and California are slated to receive upgrades soon as well. Increasing the power of those antennas isn’t their only purpose. With so much additional data being sent between handlers and spacecraft, increasing data transfer rates is another focal point of the network upgrades. Eliminating frequency bands that specific telescopes are limited to will help the network utilize all of its resources to support all of its missions.
Not only is the DSN getting technological upgrades, but it’s also trying a new management system that will better utilize the three sites spread throughout the world. Previously, on-site managers had managed the antennas at their site locally. Now, there is a global hand-off protocol that managers call “Follow the Sun”, which allows personnel at each complex to run their entire network during their own “on” shift. This has created cost savings as well as increased coordination between the sites as it requires regular knowledge transfer about local conditions and satellite quirks.
A lot of those cost savings from the new management architecture have gone into technological upgrades for the antennas themselves. With the pace of technological advancement in the communications field, there is plenty of room for improvement, but NASA has already shown that maintaining and even upgrading their internal communication network is one of the priorities.
The Milky Way is filled with planets. Now astronomers have found the first candidate planet in another galaxy.
The M51 Whirpool GalaxyNASA, ESA, S. Beckwith (STScI) and the Hubble Heritage Team (STScI/AURA)Since the first detection of the first exoplanet in 1992, astronomers have found thousands of others. Indeed, they estimate that the Milky Way is home to 40 billion worlds.
So it’s easy to imagine that planets must be common in other galaxies, particularly those that seem similar to our own. But when it comes to spotting these planets, there is a problem.
Other galaxies are so far away and the stars crammed into such a small region of space, as seen from Earth, that it is hard to identify individual ones let alone the effects of any planets around them. So extragalactic planets have sadly eluded astronomers.about:blank
Now Rosanne Di Stefano at the Harvard-Smithsonian Center for Astrophysics along with several colleagues, say they have found a candidate planet in the M51 Whirlpool Galaxy some 23 million light years from Earth near the constellation of Ursa Major. This alien world, christened M51-ULS-1b, is probably slightly smaller than Saturn and orbits a binary system at a distance of perhaps ten times Earth’s distance from the Sun.
The observation was possible because of a special set of conditions. The planet’s host binary system consists of a neutron star or black hole which is devouring a massive nearby star at a huge rate. The infall of stardust releases huge amounts of energy, making this system one of brightest sources of X-rays in the entire Whirlpool Galaxy. Indeed, its X-ray luminosity is roughly a million times brighter than the entire output of the Sun at all wavelengths.
But the source of these X-rays — the black hole or neutron star — is tiny. That means a Saturn-sized planet orbiting a billion kilometers away can completely eclipse the X-ray source, should it pass directly in front in the line of sight with Earth.
On Sep. 20, 2012, that’s exactly what appears to have happened. Fortuitously, the orbiting Chandra X-ray Observatory was watching at the time. The X-ray source dimmed to nothing and then reappeared, the entire transit lasting about 3 hours.about:blank
At the time, nobody noticed because the data sets from Chandra weren’t being searched for such short variations. But when Di Stefano and colleagues looked, the tell tale signs were clear to see.
There are various reasons why an X-ray source can dim in this way. One is the presence of another small star, such as a white dwarf, that eclipses the X-ray source. The team says M51-ULS-1b cannot be a white dwarf or other type of star because the binary system is too young for such an object to have evolved nearby.
Another potential explanation is natural variation, perhaps because of an interruption to the material falling into the black hole or neutron star. Di Stefano and co say in these cases, the luminosity changes in a characteristic way, with higher energy light frequencies changing more quickly than lower energy ones, and switching back on in a different way.
But in this case, all the light frequencies dimmed and reappeared at the same time, suggesting an eclipse. “It is approximately symmetric, and has a shape typical of transits in which the source and transiting object have comparable size,” they say.about:blank
Now that the first planet candidate in another galaxy has emerged, Di Stefano and co say others are likely to be found quickly. The team scoured just a portion of the X-ray data from Chandra to find this new planet candidate.
There is plenty more where that data came from. “The archives contain enough data to conduct surveys comparable to ours more than ten times over,” say the team. “We therefore anticipate the discovery of more than a dozen additional extragalactic candidate planets in wide orbits.” And more data is being gathered all the time.
So while M51-ULS-1b may be the first candidate planet discovered in another galaxy, it is unlikely to be the last. Just watch this space.
The impact site (Southern North America) of the asteroid that killed the dinosaurs 65 million years ago – It is called the Chicxulub Crater ~ 200 Km in diameter.
Asteroid dust found at Chicxulub Crater confirms cause of dinosaurs’ extinction
Although an asteroid impact has long been the suspected cause of the mass extinction 66 million years ago, researchers think new evidence finally closes the case.
An asteroid smashed into the Yucatán Peninsula 66 million years ago, killing some 75 percent of life on Earth, including all non-avian dinosaurs.Willgard Krause/Pixabay
Some 66 million years ago, a city-size asteroid barreled through Earth’s atmosphere and slammed into the shallow waters off the Yucatán Peninsula in the Gulf of Mexico. The cosmic artillery strike gouged a 125-mile-wide (200 km) crater in Earth surface, lofting plumes of vaporized rock and debris into the air that globally blocked out views of the Sun for years or decades. After the initial blast, the reduced sunlight caused Earth’s surface temperature to plummet by as much as 50 degrees Fahrenheit (28 degrees Celsius), aiding in a mass extinction that killed 75 percent of life on Earth.
But eventually, the dust settled.
Fast forward to the 1980s, and scientists uncovered traces of asteroid dust, finding it scattered around the globe within the same geological layer that corresponds to the dinosaurs’ extinction. In the following decade, Chicxulub Crater was discovered in the Gulf of Mexico. And because the crater appeared to be the same age as the global rock layer enriched with asteroid dust, researchers were fairly certain they had the story of the dinosaurs’ demise figured out.about:blankabout:blank
Now, a new study seems to have officially closed the case for good.
Named after a nearby town, Chicxulub crater is located just offshore. New evidence confirms the site is almost undoubtedly the epicenter of the dinosaurs’ demise.The University of Texas at Austin/Jackson School of Geosciences/Google MapsThe latest evidence comes from rock core samples plucked from Chicxulub Crater itself, which is buried beneath the seafloor in the Gulf of Mexico. In the most recent study based on these samples, which were collected during a 2016 mission co-led by the University of Texas at Austin, researchers say they’ve found a telltale sign of asteroid dust. It comes in the form of iridium, which is common in some types of asteroids, yet rare in Earth’s crust.
The researchers found the highest concentration of iridium-peppered rock, which also contains a mixture of ash from the impact and ocean sediment, within a sample taken from the crater’s peak ring. This sample likewise shows elevated levels of other elements commonly associated with asteroids, resulting in a chemical fingerprint that resembles the asteroid dust found around the globe in the 1980s, and precisely matches the geological location of the impact itself.
Seen here is the section of rock core from Chicxulub Crater in which researchers found a concentration of iridium, a tracer for asteroid material, mixed with ash from the impact and ocean sediment.The International Ocean Discovery Program.We combined the results from four independent laboratories around the world to make sure we got this right,” said lead author Steven Goderis, a geochemistry professor at Vrije Universiteit Brussel, in a press release.
“We are now at the level of coincidence that geologically doesn’t happen without causation,” added Sean Gulick, a professor at UT Jackson School of Geoscience and co-author of the study.
Astronomers Say Giant Comets Pose a Greater Threat to Earth Than Asteroids
A team of astronomers has identified giant comets as a greater threat to life on Earth than asteroids. The biggest difference between the two celestial bodies is their composition: comets are composed of ice, dust, and rock, whereas asteroids are made up of metals and rock – which is why comets leave a ‘tail’, as the ice within them gets vapourised by the Sun.
That distinction might not mean much to the average resident of planet Earth, but another major difference between comets and asteroids is where they can be found in the Universe. Giant comets, known as centaurs (around 50-100 km or 31-62 miles across), move through unstable orbits that take them past the larger planets: Jupiter, Saturn, Uranus, and Neptune.
The gravity from these planets can deflect comets in the direction of Earth, and we’re discovering more and more of these centaurs as time goes on.
Researchers from Armagh Observatory and the University of Buckingham in the UK think this makes them a genuine threat to our home planet – more so than the asteroids that typically come closer to Earth on a regular basis, and which have been the main focus of NASA’s investigations so far.
If a centaur heading in our direction should break up into pieces, we could face an intermittent bombardment of missiles that lasts 100,000 years, according to the new report.
“In the last three decades we have invested a lot of effort in tracking and analysing the risk of a collision between Earth and an asteroid,” said one of the team, astronaut Bill Napier. “Our work suggests we need to look beyond our immediate neighbourhood too, and look out beyond the orbit of Jupiter to find centaurs. If we are right, then these distant comets could be a serious hazard, and it’s time to understand them better.”
Based on a study of ancient civilisations, the terrestrial environment and interplanetary matter close to Earth, the scientists think the remnants of a centaur may have hit our planet some 30,000 years ago. Based on a projected frequency of one centaur per 40,000 to 100,000 years, that means we’re almost due for another one.
The cratering patterns found on Earth and the Moon suggest the volume of near-Earth objects (NEOs) is episodic in nature, say the researchers. In other words, it varies significantly over time, and we should be prepared for another sudden increase in the number and frequency of the NEOs we potentially have to deal with. Perhaps the sooner we all vacate the planet, the better.
It could analyze a photo of the Martian surface in just five seconds. NASA scientists need 40 minutes.
If you’ve ever played one of those “spot the difference between these two photos” games, you have something in common with NASA scientists.
To identify newly formed craters on Mars, they’ll spend about 40 minutes analyzing a single photo of the Martian surface taken by the Context Camera on NASA’s Mars Reconnaissance Orbiter (MRO), looking for a dark patch that wasn’t in earlier photos of the same location.
If a scientist spots the signs of a crater in one of those images, it then has to be confirmed using a higher-resolution photograph taken by another MRO instrument: the High-Resolution Imaging Science Experiment (HiRISE).
This method of spotting new craters on Mars makes it easy to determine an approximate date for when each formed — if a crater wasn’t in a photo from April 2016 but is in one from June 2018, for example, the scientists know it must have formed sometime between those two dates.
By studying the characteristics of the craters whose ages they do know, the scientists can then estimate the ages of older ones. This information can improve their understanding of Mars’ history and help with the planning of new missions to the Red Planet.
The problem: this is incredibly time-consuming.
The MRO has been taking photos of the Red Planet’s surface for 15 years now, and in that time, it has snapped 112,000 lower-resolution images, with each covering hundreds of miles of the Martian surface.
To free scientists from the burden of manually analyzing all those photos, researchers trained an algorithm to scan the same images for signs of new craters on Mars — and it only needs about five seconds per picture.
Fresh craters on Mars
To train their image-analyzing AI to spot new craters on Mars, the researchers started by feeding it nearly 7,000 images from the Context Camera. Some featured fresh craters confirmed by HiRISE photos, and others didn’t.
After training, the next step was letting the algorithm analyze all of the Context Camera images.
This is just beginning. We’re looking forward to finding a lot more.
To speed it up, the researchers ran the AI on a supercomputer cluster at NASA’s Jet Propulsion Laboratory (JPL).
“It wouldn’t be possible to process over 112,000 images in a reasonable amount of time without distributing the work across many computers,” JPL computer scientist Gary Doran said in October. “The strategy is to split the problem into smaller pieces that can be solved in parallel.”
With the power of all those computers combined, the AI could scan an image in an average of just five seconds. If it flagged something that looked like a fresh crater, NASA scientists could then check it out themselves using HiRISE.
Scanning the Martian surface
In October, NASA confirmed that the AI had discovered its first fresh craters on Mars, and to date, it’s helped scientists spot dozens of new impacts in the Context Camera images.
“The data was there all the time,” JPL computer scientist Kiri Wagstaf told Wired. “It’s just that we hadn’t seen it ourselves.”
In the future, the AI might help scientists identify more craters on Mars — potentially within weeks of their formation — or even craters on other planets.
“The possibility of using machine learning to really delve into large data sets and find things that we otherwise wouldn’t have found is really exciting,” Ingrid Daubar, a planetary scientist who helped create the AI, told Wired.
“This is just beginning,” she added. “We’re looking forward to finding a lot more.”