About this world
HD 16417 b is a Neptune-like planet orbiting HD 16417, a yellow, Sun-like star (type G1V) 82.8 light-years from Earth. It is about 5 times the size of Earth (its size estimated from its mass), with at least 22 Earth masses (a minimum, measured by radial velocity). It completes an orbit every 17.2 days at 0.14 AU from its star, closer than Mercury is to the Sun.
Its equilibrium temperature is about 964 K (691 °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 Anglo-Australian Telescope. The star wobbles toward and away from us, Doppler-shifting its spectrum.