About this world
Teegarden's Star b is an Earth-sized planet orbiting Teegarden's Star, a cool red dwarf (type M7.0V) 12.5 light-years from Earth. It is about 1.1 times the size of Earth (its size estimated from its mass), with at least 1.2 Earth masses (a minimum, measured by radial velocity). It completes an orbit every 4.91 days at 0.026 AU from its star, closer than Mercury is to the Sun.
Its equilibrium temperature is about 277 K (4 °C), which places it in the optimistic 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 2019 by radial velocity with Calar Alto Observatory. The star wobbles toward and away from us, Doppler-shifting its spectrum. Teegarden's Star has 3 known planets; the others are Teegarden's Star c and Teegarden's Star d.