TOI-782 b: A Distant Neptune-like World

TOI-782 is a star 171 light-years from Earth, and one planet orbits it, named TOI-782 b. The host star has a reported mass of 0.397 solar masses and a radius of 0.413 solar radii, both smaller than the Sun's corresponding values, and its temperature of 3370 K is cooler than the Sun's.

TOI-782 b is a Neptune-like planet, a size class that compares its radius with Earth's rather than describing its composition. Its radius of 2.73 Earth radii is larger than Earth's. It was discovered in 2024 by the transit method, in which a planet passing in front of its star from our viewpoint causes a small dip in observed brightness. Repeated dips help establish orbital periods, and TOI-782 b completes its orbit every 8.02 days. Its mass is a reported upper limit of 19.1 Earth masses, a bound rather than an exact value.