MOA-2011-BLG-262L

MOA-2011-BLG-262L is a red dwarf with an orbiting exoplanet, both detected through the gravitational microlensing event MOA-2011-BLG-262.^[3] It was once believed to be either an exoplanet with 3.2 times the mass of Jupiter and a exomoon with 0.47 times Earth's mass or a red dwarf with a mass of 0.11 solar masses orbited by a ~17 M_🜨 planet,^[2][4] but the latter scenario was confirmed in 2024 based on observations of the host star by the Keck telescope, 10 years after the ending of the microlensing event.^[3]

An artist's rendition of the system as a rogue planet with a moon (left) and a star with a planet (right); since 2024, the scenario on the right has been confirmed as the actual system

MOA-2011-BLG-262L

Observation data Epoch J2000      Equinox J2000
Constellation	Sagittarius[1]
Right ascension	18h 00m 23.48s[2]
Declination	−31° 14′ 42.93″[2]
Characteristics
Apparent magnitude (K)	22.3
Astrometry
Distance	24,400±3,000 ly (7,490±910 pc)[3]
Details[3]
Mass	0.193±0.029 M☉
Database references
SIMBAD	data

The system is located 24,400 light-years from Earth, in the constellation Sagittarius.^[1] The host star is a red dwarf, with 19% the Sun's mass and a faint apparent magnitude of 22.3 in the K-band. It has a transverse velocity of 541.3±65.75 km/s, the highest ever found for any star with a known exoplanet.^[3]

The MOA-2011-BLG-262L planetary system^[3]

Companion (in order from star)	Mass	Semimajor axis (AU)	Orbital period (days)	Eccentricity	Inclination	Radius
b	28.92±4.75 M🜨	0.98+0.56 −0.20	—	—	—	—