Pollux b

extrasolar planet

Pollux b, (also known as Beta Geminorum b and HD 62509 b, formally named Thestias), is an extrasolar planet about 34 light years away in the constellation of Gemini. This planet was discovered orbiting the star Pollux in 2006 by the astronomer, Artie P. Hatzes, confirming his hypothesis originally published in 1993. The planet has twice the mass of Jupiter. It moves around its star in 1.61 years at a distance of 1.64 AU in a nearly circular orbit.

Pollux B

In July 2014 the International Astronomical Union (IAU) launched NameExoWorlds, a process for giving proper names to certain extrasolar planets and their host stars.[1] The process involved public nomination and voting for the new names.[2] In December 2015, the IAU announced the winning name was Thestias for this planet.[3] The winning name was based on that originally submitted by theSkyNet of Australia; specifically Leda, Pollux's mother in Greek and Roman mythology. At the request of the IAU, 'Thestias' (the patronym of Leda, a daughter of Thestius) was substituted. This was because 'Leda' was already attributed to an asteroid known as 38 Leda and to one of Jupiter's satellites known as Leda.[4][5]


  1. "International Astronomical Union | IAU". www.iau.org. Retrieved 2022-11-17.
  2. "NameExoWorlds". 2015-08-15. Archived from the original on 2015-08-15. Retrieved 2022-11-17.
  3. "International Astronomical Union | IAU". www.iau.org. Retrieved 2022-11-17.
  4. "NameExoWorlds". 2018-02-01. Archived from the original on 2018-02-01. Retrieved 2022-11-17.
  5. "YOU helped name an exoplanet!". www.theskynet.org. Archived from the original on 2018-05-07. Retrieved 2022-11-17.