About this world
Wolf 1061 d is a sub-Neptune orbiting Wolf 1061, a cool red dwarf (type M3.5) 14 light-years from Earth. It is about 2.7 times the size of Earth (its size estimated from its mass), with at least 7.7 Earth masses (a minimum, measured by radial velocity). It completes an orbit every 217 days at 0.47 AU from its star, on a strongly elongated orbit (e = 0.55).
Its equilibrium temperature is about 130 K (−143 °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 2015 by radial velocity with La Silla Observatory. The star wobbles toward and away from us, Doppler-shifting its spectrum. Wolf 1061 has 3 known planets; the others are Wolf 1061 b and Wolf 1061 c.