Gaia-1 is a Sun-like G-type star (about 0.95 solar masses, 5,470 K, 0.95 solar radii), 364 light-years from Earth. Gaia-1 b is a 1.68-Jupiter-mass companion, with an orbital period of 3.1 days, at 0.040 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-1 b skims its star closer than Mercury orbits the Sun.