About this world
HD 21411 b is a Neptune-like planet orbiting HD 21411, a yellow, Sun-like star (type G8V) 95 light-years from Earth. It is about 0.85 times the size of Jupiter (its size estimated from its mass), with at least 0.21 Jupiter masses (a minimum, measured by radial velocity). It completes an orbit every 84.3 days at 0.36 AU from its star, closer than Mercury is to the Sun, on a strongly elongated orbit (e = 0.4).
Its equilibrium temperature is about 408 K (135 °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 2019 by radial velocity with Las Campanas Observatory. The star wobbles toward and away from us, Doppler-shifting its spectrum.