HAT-P-39 is a star with 1.4 times the mass of the Sun, and 1.62 times its radius. It is located 2273.32 light years away from the solar system and is estimated to be 2 billion years old, as compared to the Sun which is roughly 4.6 billion years old.
HAT-P-39 is known to have 1 exoplanets in orbit around it.
HAT-P-39 b was discovered by the HATNet observatory, in 2012-11, using the transit method. Its semi-major axis is 0.05 astronomical units, as compared to Earth's which is 1 astronomical unit. The mass of HAT-P-39 b is 190.482 times the mass of Earth. The radius of HAT-P-39 b is 17.609 that of Earth. At more than 50 Earth masses, HAT-P-39 b is a gas giant, a planet whose mass is mostly made up of hydrogen and helium, like Jupiter and Saturn in our solar system.