TOI-5261 is a Sun-like G-type star (about 1.04 solar masses, 5,790 K, 1.02 solar radii), 377 light-years from Earth. TOI-5261 b is a 11.5-Jupiter-mass companion, with an orbital period of 4.2 days, at 0.051 AU from its star, and an equilibrium temperature near 1,244 K, on an eccentric orbit (e ≈ 0.16), discovered in 2025 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.