About this world
Kepler-51 e is a sub-Neptune orbiting Kepler-51, a yellow-white F-type star 2.56 thousand light-years from Earth. It is about 2.2 times the size of Earth (its size estimated from its mass) and holds 5.4 Earth masses. It completes an orbit every 264 days at 0.82 AU from its star.
Its equilibrium temperature is about 284 K (11 °C), which places it in the conservative habitable zone: the band where liquid water could exist on a rocky surface. By the "cosmic shoreline", it has likely held on to an atmosphere.
It was discovered in 2024 by timing variations with Multiple Observatories. Pulsar, eclipse or transit timings drift as an unseen companion tugs on them. Kepler-51 has 4 known planets; the others are Kepler-51 b, Kepler-51 c and Kepler-51 d.