Pollux is Beta Geminorum, apparent magnitude 1.14, at roughly 34 light years, the brightest star in Gemini and the nearest bright giant to the Sun. It is an orange giant of type K0, and it hosts a confirmed planet, a gas giant several times the mass of Jupiter, detected by the wobble it induces and formally named Pollux b, one of the first exoplanets found around a bright, easily seen star. Pollux and Castor together mark the heads of the two twins.
Pollux b, confirmed in 2006, orbits at roughly 1.6 astronomical units, well within what would be the frost line of a Sun-like star but here scorched by Pollux's much greater luminosity as an evolved giant; it was among the first planets found around a star bright enough to be a familiar naked-eye object rather than a faint telescopic target, which made it something of a landmark discovery for public interest in exoplanets. Pollux's confirmed planet has renewed astronomical interest in a star that medieval and Renaissance observers knew only as a bright naked-eye point, a reminder that even the most historically storied stars can still yield new discoveries under modern instruments. Its designation as Beta rather than Alpha, despite outshining Castor, is one of the more frequently noted exceptions to Bayer's rough brightness-ordering convention.
Sources AstronomyAndrew Fraknoi, David Morrison, and Sidney C. Wolff (OpenStax) with Almagest (Mathematike Syntaxis)Claudius Ptolemy