LP 890-9 b

Lore & Background

LP 890-9 b was first detected by the Transiting Exoplanet Survey Satellite (TESS) and subsequently confirmed through follow-up observations with the SPECULOOS facility. It is the inner planet of the system, with LP 890-9 c orbiting farther out. Both planets are likely terrestrial and somewhat larger than Earth. The host star is extremely faint, with an apparent magnitude of 18, making it the faintest star with exoplanets discovered by TESS.

Reader's Guide

LP 890-9 b is notable as the first planet discovered in the LP 890-9 system, a red dwarf that is the faintest star known to host exoplanets detected by TESS. Its discovery helped confirm the existence of the outer planet LP 890-9 c, which orbits within the habitable zone and is a target for atmospheric characterization with JWST. While LP 890-9 b itself is not in the habitable zone, its detection demonstrated the capability of TESS and SPECULOOS to find planets around extremely dim stars. The planet's terrestrial nature and size slightly larger than Earth place it among the growing population of small exoplanets around red dwarfs. The system as a whole provides a comparative laboratory for studying planetary formation and evolution around low-mass stars, with LP 890-9 b serving as the inner benchmark for understanding the system's architecture.

Did You Know?

• The host star LP 890-9 has 12% the mass and 15% the radius of the Sun.
• LP 890-9 is the faintest star with exoplanets discovered by TESS, with an apparent magnitude of 18.
• Both LP 890-9 b and c are likely terrestrial planets somewhat larger than Earth.