TOI-4860 b: A Jupiter-Like World Around a Small Red Dwarf

TOI-4860 is an M-type dwarf, a small, cool red dwarf, with a spectral type of M4.5+/-0.5, lying 261 light-years away. Its reported mass is 0.336 solar masses and its reported radius is 0.348 solar radii, both smaller than the Sun's, and its reported temperature of 3390 K is cooler than the Sun's. The star's age is given as a reported lower limit of 4.5 billion years. One planet is known to orbit this host.

That planet is TOI-4860 b, a Jupiter-like planet discovered by the transit method in 2023. A transit occurs when a planet passes in front of its star from our viewpoint, causing a small dip in observed brightness. TOI-4860 b has a mass of 86.7 Earth masses and a radius of 8.7 Earth radii, both larger than Earth's corresponding values. Its orbital period is 1.52 days. A size class such as Jupiter-like reflects radius relative to Earth's rather than composition. The planet's mean density is 0.725 g/cm³, 0.132 times Earth's.