About this world
LSPM J2116+0234 b is a sub-Neptune orbiting LSPM J2116+0234, a cool red dwarf (type M3.0V) 57.5 light-years from Earth. It is about 3.7 times the size of Earth (its size estimated from its mass), with at least 13 Earth masses (a minimum, measured by radial velocity). It completes an orbit every 14.4 days at 0.088 AU from its star, closer than Mercury is to the Sun.
Its equilibrium temperature is about 372 K (99 °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 2019 by radial velocity with Calar Alto Observatory. The star wobbles toward and away from us, Doppler-shifting its spectrum.