WASP-2 is a binary star system in the Delphinus constellation located about 500 light-years away.[1] The primary is magnitude 12 orange dwarf star, orbited by red dwarf star on wide orbit.[2] The star system shows an infrared excess noise of unknown origin.
This star has one extrasolar planet WASP-2b, detected by the SuperWASP project in 2006.
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 2.2m (07.2feet) 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.[3]
The re-examination of the WASP-2 spectrum in 2015, have resulted in the measurement of stellar companion temperature equal to 3513 K, and angular separation of 0.73 arc second.