TOI-2109 b: A Jupiter-Like World in a Close Orbit

TOI-2109 is an F-type star 855 light-years away with a single known planet orbiting it. The star is 1.77 billion years old and has a mass of 1.45 solar masses, a radius of 1.7 solar radii, and a temperature of 6540 K, making it more massive, larger, and hotter than the Sun.

The only known planet around TOI-2109 is TOI-2109 b, a Jupiter-like world discovered in 2021 by the transit method, in which a planet passing in front of its star briefly dims the star's light. Its radius of 15.1 Earth radii, well beyond the four-Earth-radius threshold for Jupiter-like planets, is larger than Earth's. Its mass of 1600 Earth masses, also larger than Earth's, is roughly 5.02 times Jupiter's mass. The planet completes an orbit every 0.672 days. Its mean density is 2.55 g/cm³, 0.464 times Earth's.