GJ 3942 is a star with 0.63 times the mass of the Sun, and 0.61 times its radius. It is located 55.21 light years away from the solar system.
GJ 3942 is known to have 1 exoplanets in orbit around it.
GJ 3942 b was discovered by the Roque de los Muchachos Observatory observatory, in 2017-12, using the radial velocity method. Its semi-major axis is 0.06 astronomical units, as compared to Earth's which is 1 astronomical unit. The mass of GJ 3942 b is 7.142 times the mass of Earth. The radius of GJ 3942 b is 2.570 that of Earth. At more than 10 Earth masses, GJ 3942 b is an ice giant, a planet that is made up mostly of volatiles like water, amonia and methane, and enveloped by a dense hydrogen and helium atmosphere, much like Uranus and Neptune in our solar system.