A group of astronomers making routine measurements on a star have found the first confirmed evidence of a planet orbiting a star other than our sun.
David W. Latham, who led the team that made the discovery, said the planet is 30,000 times larger than the Earth and probably lifeless because it would have a surface temperature of hundreds of degrees."It's much hotter than an oven," said Latham. "This is not a place you would look for life."
The planet is so close to its star that it orbits once every 84 days, Latham said. Mercury, the planet closest to our own sun, has an orbit of 87 days.
Latham reported on the discovery Wednesday at the 20th general assembly of the International Astronomical Union in Baltimore.
Latham and his team found the planet while running instrument tests on a star called HD 114762. He said the star was one of a group called "candidate standard stars" that astronomers have been measuring for years to establish the characteristics of basic star types. The study is being conducted to give astronomers worldwide a standard for calibrating instruments.
Using light gathered by a 61-inch reflector telescope at the Oak Ridge Observatory in Massachusetts, the astronomers processed the star sightings through an instrument called the photon counting system.
The instrument detected a slight wobble in the motion of the star that could only be caused by a nearby orbiting body.
Latham said the planet would have to be massive, some 20 times larger than Jupiter, the largest planet in the solar system, in order to give star HD 114762 such a wobble.
"It's at the upper edge (of being the size) of a planet," Latham said. Minimum starlike bodies are usually 100 times the size of Jupiter.
Despite its size, the planet is too small and too distant - 90 light years from Earth - to be seen directly.