About this world
HD 48948 b is a sub-Neptune orbiting HD 48948, an orange dwarf (type K3V) 55.1 light-years from Earth. It is about 2.1 times the size of Earth (its size estimated from its mass), with at least 4.9 Earth masses (a minimum, measured by radial velocity). It completes an orbit every 7.34 days at 0.065 AU from its star, closer than Mercury is to the Sun.
Its equilibrium temperature is about 957 K (684 °C): far too hot for liquid water on its surface. By the "cosmic shoreline", its star has probably stripped its atmosphere away, leaving bare rock.
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 c and HD 48948 d.