XO-1b (Also known as GSC 02041-01657b) is an extrasolar planet orbiting the star XO-1 in the constellation Corona Borealis, which is located about 600 light-years away. Their discovery is part of project XO’s efforts.

Its radius and mass indicate that it is possibly a gas giant, with a composition similar to Jupiter. However, its condition with respect to its star is quite different, since the distance to its star is even less than that of Mercury. In this way, the planet would be classified as a hot Jupiter, such as HD 209458 b, TrES-1 or WASP-1b.

Its low density (just over half that of water) indicates that it would consist mostly of hydrogen and helium.


Observations of XO-1b

Collaborative projects