The Breakthrough Listen Initiative, the largest ever scientific research program aimed at finding evidence of alien civilizations, has conducted a search for artificial radio emission associated with Kepler-160, a system of four planets that includes the newly-discovered habitable-zone planet Kepler-160e.
An artist’s impression of a four-planet system. Image credit: Sci-News.com.
Kepler-160 is approximately 3,141 light-years away toward the constellation of Lyra.
This Sun-like star is about 12% bigger than our Sun, just 1% more luminous, and is home to at least four massive planets: Kepler-160b, c, d and e.
The planets Kepler-160b, c and d are between 1.7 and 3.1 times the size of Earth and have orbital periods less than 50 days.
The outermost planet, Kepler-160e (also designated KOI-456.04), has a radius of 1.9 times that of the Earth and an orbital period of 378 days.
The alien world, found earlier this year in data from NASA’s Kepler Space Telescope, is in the habitable zone of the host star and has an estimated surface temperature of minus 28 degrees Celsius (minus 18 degrees Fahrenheit).
“This Earth-like planet candidate, given its ideal location in the habitable zone of its host star and edge-on orientation projected toward Earth, represents an ideal target for technosignature searches,” said Columbia University astronomer Karen Perez and colleagues.
The researchers observed the Kepler-160 system using the Robert C. Byrd Green Bank Telescope as part of the ongoing Breakthrough Listen search for alien technosignatures.
The Robert C. Byrd Green Bank Telescope in Green Bank, West Virginia, the United States. Image credit: Jiuguang Wang / CC BY-SA 2.0.
“We searched the radio frequency bands 1.1-1.9 GHz (L-band), 1.8-2.8 GHz (S-band), and 3.95-8 GHz (C-band) for narrowband Doppler-accelerated and wideband artificially-dispersed technosignatures,” they explained.
“We observed Kepler-160 with the Green Bank Telescope for three 5-minute pointings at each frequency band, beginning on June 14, 2020 11:13 UT.”
The scientists did not find any artificial radio signal from the Kepler-160 planetary system.
“Future observations of Kepler-160e with future missions, like PLATO, might recover its transit, confirming its candidacy as a planet and aiding in any further radio observations,” they said.
“Additionally, we expect to carry similar searches towards other exoplanet systems and candidates as more targets of interest are discovered using ongoing missions such as TESS and K2.”
The team’s paper was published online this week on the research website arXiv.org.