About this world
GJ 687 b is a Neptune-like planet orbiting GJ 687, a cool red dwarf (type M3.0V) 14.8 light-years from Earth. It is about 4.3 times the size of Earth (its size estimated from its mass), with at least 17 Earth masses (a minimum, measured by radial velocity). It completes an orbit every 38.1 days at 0.16 AU from its star, closer than Mercury is to the Sun.
Its equilibrium temperature is about 264 K (−9 °C), which places it in the conservative habitable zone: the band where liquid water could exist on a rocky surface. At its size it almost certainly keeps a deep envelope of hydrogen and helium.
It was discovered in 2014 by radial velocity with Lick Observatory. The star wobbles toward and away from us, Doppler-shifting its spectrum. GJ 687 has 2 known planets; the others are GJ 687 c.