Ross 508 and Its Planet

Ross 508 is an M4.5 V star, a small, cool red dwarf, located 36.6 light-years away. Its reported mass is 0.177 solar masses, its reported radius is 0.211 solar radii, and its temperature is 3070 K. The star's reported mass and radius estimates are smaller than the Sun's, and its reported temperature is cooler than the Sun's. One planet is known to orbit this host.

Ross 508 b was discovered in 2022 using the radial velocity method, which detects the wobble a planet's gravity induces in its star's motion; repeated wobbles reveal the planet and its orbital period. The planet has a minimum mass of 4 Earth masses, a lower bound on its true mass, and an orbital period of 10.8 days. Its minimum mass is larger than Earth's.