May 28, 2009
New technique finds Jupiter-like exoplanet
The U.S. space agency says a new planet-hunting technique has recorded its first discovery -- a Jupiter-like planet orbiting one of the smallest stars known.
The National Aeronautics and Space Administration said the technique, called astrometry, involves measuring the motions of a star as an unseen planet tugs the star back and forth. However, the method had failed to identify any exoplanets.
But now two astronomers from NASA's Jet Propulsion Laboratory using the technique have identified a new exoplanet around one of 30 stars they studied. It's the first exoplanet to be discovered using astrometry.
We found a Jupiter-like planet at around the same relative place as our Jupiter, only around a much smaller star, NASA astronomer Steven Pravdo, lead author of the study, said.
It's possible this star also has inner rocky planets. And since more than seven out of 10 stars are small like this one, this could mean planets are more common than we thought.
The newly found exoplanet is about 20 light-years from Earth in the constellation Aquila.
This is an exciting discovery because it shows that planets can be found around extremely light-weight stars, Wesley Traub, chief scientist for NASA's Exoplanet Exploration Program, said.
This is a hint that nature likes to form planets, even around stars very different from the sun.
The research is to appear in the Astrophysical Journal.