About this world
Gliese 12 b is an Earth-sized planet orbiting Gliese 12, a cool red dwarf (type M4V) 39.8 light-years from Earth. It is about 0.93 times the size of Earth and holds 0.95 Earth masses. It completes an orbit every 12.8 days at 0.067 AU from its star, closer than Mercury is to the Sun, on a strongly elongated orbit (e = 0.24).
Its equilibrium temperature is about 315 K (41 °C): too cold for liquid water on its surface. By the "cosmic shoreline", its star has probably stripped its atmosphere away, leaving bare rock.
It was discovered in 2024 by transit with Transiting Exoplanet Survey Satellite (TESS). A planet crosses its star and dims it by a tiny, periodic fraction.