About this world
Kepler-451 d is a gas giant orbiting 2MASS J19383260+4603591, a hot blue star 1.29 thousand light-years from Earth. It is about 1.2 times the size of Jupiter (its size estimated from its mass), with at least 1.8 Jupiter masses (a minimum, measured by radial velocity). It completes an orbit every 43 days at 0.19 AU from its star, closer than Mercury is to the Sun.
Its equilibrium temperature is about 1,480 K (1,207 °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 timing variations with Multiple Observatories. Pulsar, eclipse or transit timings drift as an unseen companion tugs on them. 2MASS J19383260+4603591 has 3 known planets; the others are 2MASS J19383260+4603591 b and Kepler-451 c.