About this world
GJ 328 b is a gas giant orbiting GJ 328, a cool red dwarf (type M0.0) 66.9 light-years from Earth. It is about 1.2 times the size of Jupiter (its size estimated from its mass), with at least 2.5 Jupiter masses (a minimum, measured by radial velocity). It completes an orbit every 10.3 years at 4.1 AU from its star, on a strongly elongated orbit (e = 0.23).
Its equilibrium temperature is about 74 K (−200 °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 2013 by radial velocity with McDonald Observatory. The star wobbles toward and away from us, Doppler-shifting its spectrum. GJ 328 has 2 known planets; the others are GJ 328 c.