WASP-18
WASP-18 is a magnitude 9 star located in the Phoenix constellation of the southern hemisphere. It has a mass of 1.25 solar masses.
In 2009, the SuperWASP project announced that a large, hot Jupiter type extrasolar planet, WASP-18b, was orbiting very close to this star.
Observations from the Chandra X-ray Observatory failed to find any X-rays coming from WASP-18, and it is thought that this is caused by WASP-18b disrupting the star's magnetic field by causing a reduction in convection in the star's atmosphere. Tidal forces from the planet may also explain the higher amounts of lithium measured in earlier optical studies of WASP-18.
