HAT-P-28 is a Sun-like G-type star (about 1.02 solar masses, 5,680 K, 1.10 solar radii), 401 light-years from Earth. HAT-P-28 b is a 0.63-Jupiter-mass companion, with an orbital period of 3.3 days, at 0.043 AU from its star, and an equilibrium temperature near 1,384 K, on an eccentric orbit (e ≈ 0.05), discovered in 2011 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.