XO-2 N is a Sun-like G-type star (about 0.96 solar masses, 5,290 K, 1.00 solar radii), 154 light-years from Earth. XO-2 N b is a 0.59-Jupiter-mass companion, with an orbital period of 2.6 days, at 0.037 AU from its star, discovered in 2007 via transit. The inner world is a hot Jupiter — a gas giant hugging its star at a fraction of Mercury's distance — a class that forced astronomers to rethink how giant planets form and migrate inward. XO-2 N b skims its star closer than Mercury orbits the Sun.