TRAPPIST-1: What Would Life On These Exoplanets Be Like?

Seven Earth-size planets were found orbiting the ultracool dwarf star TRAPPIST-1. Since three of these planets reportedly lie within the star's habitable zone, what would life on these exoplanets be exactly like?

Space.com reported that living on TRAPPIST-1 planets is nothing like life on Earth. Although it is just located 39 lightyears away from the planet, there are some major differences that would make people reconsider transferring to the other worlds.

All of the planets orbiting the TRAPPIST-1 star are closer than the proximity of Mercury and the Sun (43.5 million miles at maximum distance). The closeness of the innermost and the outermost planets is about 30 times the proximity of Earth and Venus (with a maximum distance of 162 million miles). This means the orbital period of these exoplanets are way shorter than the planets in the Solar System. Six of the planets reportedly complete their orbits from 1.5 to 12.4 Earth days and scientists believe that the most distant planet's orbital period is only about 20 days.

This is because TRAPPIST-1, which size is just a bit bigger than Jupiter, is an ultracool dwarf star. It is almost 2,000 times dimmer than the Sun, making its perpetual natural lighting appear as dim as twilight on Earth.

The best thing about living in the TRAPPIST-1 system, though, is the sky spectacle. People could see six other planets without the need of a telescope. In fact, in some cases, neighboring planets could appear twice as huge as the full moon seen from Earth.

However, scientists say that these planets are tidally locked. In other words, only one side of each of these planets is facing the star. This means that these particular sides could be extremely hot at eternal daytime, while the other sides are perpetually doomed to frozen nights.

Scientists have not lost their hope on these planets' habitability, though. "We will look at atmospheres effectively in different wavelengths, allowing us to get the composition, temperature, pressure," said new TRAPPIST-1 study author Julien de Wit, a postdoctoral researcher at the Massachusetts Institute of Technology, Cambridge in a NASA press release. "This will allow us to constrain habitability."