Learn the name of TRAPPIST-1. Loaded with Earth-sized planets, this solar system will provide astronomers with the exciting opportunity to learn more about rocky worlds like our own. Three of its planets are even located within the habitable zone, meaning there could be a high chance they support liquid water.
At just forty light-years away, the alien worlds orbit a nearby ultra-cool dwarf star, TRAPPIST-1. The star is both smaller and cooler than our Sun, which means its habitable zone — the distance at which a planet is most likely to have liquid water — is closer to the star than it is in our solar system. For some perspective, all seven Earth-like planets are closer to their star than Mercury is to the Sun. In fact, the orbits are so close that if we were to stand on the surface of one of Trappist-1’s planets and gaze up, the other planets would sometimes appear even bigger than the Moon does in the skies above Earth, as you can see in this video:
Similar to Mercury and our Sun, some of the planets may be tidally locked to their star, resulting in perpetual days and eternal nights. The strong temperature differentials between these two sides would likely create some extreme weather conditions, such as intense winds.
The TRAPPIST-1 system was observed by the Spitzer Space Telescope nearly continuously for 500 hours in the fall of 2016. “This is the most exciting result I have seen in the 14 years of Spitzer operations,” said Sean Carey, manager of NASA’s Spitzer Science Center in a press release. Spitzer is scheduled to make follow-up observations in the autumn of 2017, giving scientists the chance to examine the planets’ atmospheres.
However, Spitzer isn’t the only one getting in on the game. Exoplanet-hunting powerhouse, Kepler Space Telescope, will wrap up their observations in early March 2017. The Hubble Space Telescope has also begun its investigation of the solar system by setting its sights on the atmospheres of the two planets closest to the sun. More observations are planned for another four planets, including three in the habitable zone. So far, these observations support the idea that these Earth-sized planets are also rocky terrestrial worlds like ours.
All this data will be used to help plan a more detailed investigation by the James Webb Space Telescope after it launches in 2018. The powerful new space observatory is designed to be able to detect key components of atmospheres around alien worlds, identifying water, methane, oxygen, ozone, along with planets’ temperature and surface pressure. These future observations will help to establish whether or not TRAPPIST-1’s Earth-like worlds have liquid water.
“This is a search that will go on for many generations,” exclaimed astronomer and planetary scientist Sara Seager during the NASA press conference. “We’re this close now to finding so many habitable worlds.”