Gaia-2 is a Sun-like G-type star (about 1.00 solar masses, 5,720 K, 1.06 solar radii), 209 light-years from Earth. Gaia-2 b is a 0.82-Jupiter-mass companion, with an orbital period of 3.7 days, at 0.047 AU from its star, discovered in 2022 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. Gaia-2 b skims its star closer than Mercury orbits the Sun.