About this world
HD 48948 d is a sub-Neptune orbiting HD 48948, an orange dwarf (type K3V) 55.1 light-years from Earth. It is about 3.2 times the size of Earth (its size estimated from its mass), with at least 11 Earth masses (a minimum, measured by radial velocity). It completes an orbit every 152 days at 0.49 AU from its star.
Its equilibrium temperature is about 349 K (76 °C): too cold for liquid water on its surface. At its size it almost certainly keeps a deep envelope of hydrogen and helium.
It was discovered in 2024 by radial velocity with Roque de los Muchachos Observatory. The star wobbles toward and away from us, Doppler-shifting its spectrum. HD 48948 has 3 known planets; the others are HD 48948 b and HD 48948 c.