2MASS J0249-0557 A and Its Circumbinary Companion

2MASS J0249-0557 A is an M6 V star located 215 light-years away. Its reported mass estimate is 0.295 solar masses, its reported radius estimate is 0.316 solar radii, and its reported temperature is 2860 K, all smaller or cooler than the corresponding values for the Sun. The star hosts one known planet.

That planet is 2MASS J0249-0557 c, discovered by imaging in 2018. It is a Jupiter-like planet, a class defined by a radius exceeding four times Earth's, and it is circumbinary, orbiting both stars of the binary system rather than one star alone. Its reported radius estimate is 17.4 Earth radii and its reported mass estimate is 3620 Earth masses, roughly 11.4 times Jupiter's mass. Both values exceed Earth's corresponding figures, and its mean density is 3.8 g/cm³, 0.69 times Earth's. No orbital period is reported for 2MASS J0249-0557 c.