BBC News Sci/Tech: Planet found orbiting two stars
August 20, 1999
Discovered! A planet that orbits twin stars.
For the first time, astronomers may have discovered a planet that orbits two
stars. Binary stars are very common, and theoretically it is possible for a
planet to orbit two stars. And although planets have been found orbiting one
of a pair of stars, no planets have been spotting both stars of a binary
star system - until now. A 'micro-lensing' event allowed the discovery.
These occur when an object, such as a dim star or planet, passes directly
between Earth and another star. The gravity of the intervening star or
planet acts like a magnifying glass, improving the view of the more distant
star. In June, the 'gravity lens' allowed astronomers to see a specific
pattern of light that could not be due to just one star - it needed two
stars and a planet to explain it. It is thought that the two stars are both
smaller and dimmer than our Sun, and orbit each other at a distance of 240
million kilometres. Outside these stars, a Jupiter-sized planet orbits the
pair at a distance of about 1050 million kilometres.
Back to ASTRONET's home page
Terug naar ASTRONET's home page