Early this year , NASA ’s Transiting Exoplanet Survey Satellite ( TESS ) discovered its first nearby topnotch - Earth and research worker have evidence suggesting that two more similar - sized major planet are orbiting the same star , and one of them might have the conditions for life .
As reported inAstronomy & Astrophysics , the system , called GJ 357 , is located 31 light - long time away , just down the route in astronomic terms . It ’s compose of an M - dwarf star , close to one - third the size of our Sun , and three planet . In purchase order of both size and space from their star topology , these planets are know as GJ 357 b , GJ 357 c , and GJ 357 d. The latter could be up to seven time great than Earth .
Planets deoxycytidine monophosphate and ergocalciferol were not observe immediately by TESS but their presence was reap by substance of other properties of the system . GJ 357 500 is particularly interesting because it receives roughly 40 pct of the stellar radiation Earth gets from the Sun , so it is the so - called habitable zone around the star .
In a secondpaper , accept for publication in The Astrophysical Journal Letters , part of the team investigated the habitability of GJ 357 d and what its clime might be like . Based on their model , if it is correspondent to Earth , this world could be a frozen stony satellite . But if the planet has more carbon dioxide available , then it could be moderate .
This is a big if but it is not an unconvincing one . If watch - up research can observe the satellite transiting , GJ 357 d would become the closest potentially inhabitable exoplanet to Earth . And , patently , astronomer are very interested in this physical object .
" This is exciting , as this is humanity ’s first nearby topnotch - Earth that could harbour life story – uncovered with help from TESS , our small , mighty mission with a huge scope , " lead author of the second study Professor Lisa Kaltenegger , director of Cornell ’s Carl Sagan Institute and a member of the TESS science squad , say in astatement .
The closeness of the major planet is key for future elaborate notice . We may be able to characterize its air with high preciseness and that might mean seeing signature that suggest at the bearing of life .
While the discovery of the system of rules is certainly thanks to TESS , the investigator also looked at about two decades ' worth of observations on the star . Using that data , they found insidious gravitational tugs on the star that are because of all three major planet , and could n’t have been produced by GJ 357 b alone .
