WASP-33 is a Sun-like F-type star (about 1.50 solar masses, 7,430 K, 1.44 solar radii), 122 light-years from Earth. WASP-33 b is a retrograde hot Jupiter orbiting a pulsating A-type star, so stellar vibrations and the planet interact. WASP-33 b is a 2.09-Jupiter-mass companion, with an orbital period of 1.2 days, at 0.024 AU from its star, and an equilibrium temperature near 2,782 K, discovered in 2010 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.