About this world
HD 11964 c is a Neptune-like planet orbiting HD 11964, a yellow, Sun-like star (type G9VCN+1) 109 light-years from Earth. It is about 5.4 times the size of Earth (its size estimated from its mass), with at least 25 Earth masses (a minimum, measured by radial velocity). It completes an orbit every 37.9 days at 0.23 AU from its star, closer than Mercury is to the Sun, on a strongly elongated orbit (e = 0.3).
Its equilibrium temperature is about 758 K (484 °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 2008 by radial velocity with W. M. Keck Observatory. The star wobbles toward and away from us, Doppler-shifting its spectrum. HD 11964 has 2 known planets; the others are HD 11964 b.