About this world
GJ 1151 c is a sub-Neptune orbiting GJ 1151, a cool red dwarf (type M4.5V) 26.2 light-years from Earth. It is about 3.3 times the size of Earth (its size estimated from its mass), with at least 11 Earth masses (a minimum, measured by radial velocity). It completes an orbit every 390 days at 0.57 AU from its star.
Its equilibrium temperature is about 88 K (−185 °C): too cold for liquid water on its surface. At its size it almost certainly keeps a deep envelope of hydrogen and helium.
It was discovered in 2023 by radial velocity with Multiple Facilities. The star wobbles toward and away from us, Doppler-shifting its spectrum.