WASP-2

WASP-2 is a binary star system located about 496 light-years away in the Delphinus constellation. The primary is a magnitude 12 orange dwarf star, orbited by a red dwarf star on a wide orbit. The star system shows an infrared excess noise of unknown origin.

The primary star hosts one known exoplanet, WASP-2b. Since the planet transits the star, the star is classified as a planetary transit variable and has received the variable star designation V357 Delphini.

In 2008 a study was undertaken of fourteen stars with exoplanets that were originally discovered using the transit method through relatively small telescopes. These systems were re-examined with the 2.2 m (87 in) reflector telescope at the Calar Alto Observatory in Spain. This star system, along with two others, was determined to be a previously unknown binary star system. The previously unknown secondary star is a dim magnitude 15 M-type star separated by about 111 AU from the primary, appearing offset from the primary by about one arc second in the images. This discovery resulted in a recalculation of parameters for both the planet and the primary star.

A re-examination of the WASP-2 spectrum in 2015 resulted in the measurement of the stellar companion's temperature as 3513±28 K, and an angular separation of 0.73 arcseconds.

The primary star has one exoplanet, WASP-2b, a hot Jupiter detected by the SuperWASP project in 2006 using the transit method.

• WASP-1

• "WASP-2". Exoplanets. Archived from the original on 2012-04-01. Retrieved 2009-05-04.