spacetoday.net: Hubble discovers distant exoplanet's star

Posted: Fri, Aug 11, 2006, 8:37 AM ET (1237 GMT)
Microlensed exoplanet illustration (STScI)

A distant extrasolar planet discovered three years ago has now been matched up with its parent star, astronomers reported this week. the planet was discovered in 2003 through a technique called microlensing, where the gravity of a foreground star magnifies the light of a background star when the foreground star passes directly between the background star and the Earth. That magnification turned up the existence of a small companion to the background star believed to be a planet orbiting that star. The identity of the background star could not be determined, though, until the Hubble Space Telescope observed the region and was able to distinguish the star from the foreground microlensing star. the star, called OGLE-2003-BLG-235L/MOA-2003-BLG-53L, is a red dwarf with 63 percent of the mass of the Sun and is approximately 19,000 light-years away. Based on that data, astronomers determined that the exoplanet's mass is about 2.6 times that of Jupiter.