About this world
GJ 3090 c is a sub-Neptune orbiting GJ 3090, a cool red dwarf (type M2V) 73.3 light-years from Earth. It is about 3.1 times the size of Earth (its size estimated from its mass), with at least 10 Earth masses (a minimum, measured by radial velocity). It completes an orbit every 15.9 days at 0.1 AU from its star, closer than Mercury is to the Sun.
Its equilibrium temperature is about 407 K (134 °C): far too hot for liquid water on its surface. At its size it almost certainly keeps a deep envelope of hydrogen and helium.
It was discovered in 2026 by radial velocity with Multiple Facilities. The star wobbles toward and away from us, Doppler-shifting its spectrum. GJ 3090 has 2 known planets; the others are GJ 3090 b.