About this world
CoRoT-7 d is a Neptune-like planet orbiting CoRoT-7, a yellow, Sun-like star (type G9V) 522 light-years from Earth. It is about 4.3 times the size of Earth (its size estimated from its mass) and holds 17 Earth masses. It completes an orbit every 8.97 days at 0.079 AU from its star, closer than Mercury is to the Sun.
Its equilibrium temperature is about 839 K (566 °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 2022 by radial velocity with La Silla Observatory. The star wobbles toward and away from us, Doppler-shifting its spectrum. CoRoT-7 has 3 known planets; the others are CoRoT-7 b and CoRoT-7 c.