About this world
GJ 876 e is a sub-Neptune orbiting GJ 876, a cool red dwarf (type M2.5V) 15.2 light-years from Earth. It is about 3.9 times the size of Earth (its size estimated from its mass) and holds 15 Earth masses. It completes an orbit every 124 days at 0.33 AU from its star, closer than Mercury is to the Sun.
Its equilibrium temperature is about 150 K (−123 °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 2010 by radial velocity with W. M. Keck Observatory. The star wobbles toward and away from us, Doppler-shifting its spectrum. GJ 876 has 4 known planets; the others are GJ 876 d, GJ 876 c and GJ 876 b.