The discovery of TOI 700 e was made using NASA’s Transiting Exoplanet Survey Satellite, which monitors large sections of the sky changes in stellar brightness caused by transiting planets.
The TOI 700 system is located in the southern constellation Dorado and includes planets orbiting around an M dwarf star. Previously, NASA scientists announced the discovery of TOI 700 d, a planet they believe shares similarities to Earth. Two other planets, TOI b and c, are too close to the star to be considered habitable.
TOI 700 e is the fourth planet discovered in the system, with an orbit of 28 days, and it exists in what is known as the optimistic habitable zone, where liquid water could exist on the surface at some point in the planet’s lifetime. The planet is likely rocky and is 95% of the size of Earth.
TOI 700 d, which was discovered in 2020, is in the conservative habitable zone, where scientists believe liquid water is likely to be able to exist on the surface for most of the planet’s lifetime.