Astronomers Find Planet with Similarities to Earth
RENEE MONTAGNE, host:
Astronomers say they have found a planet orbiting a distant star that's more like the Earth than any other found so far. It joins more than 150 planets discovered outside our solar system in recent years. Others look like enormous balls of gas, much bigger than Jupiter, or like huge spheres of ice, similar to Neptune. This planet appears to be small and rocky, a bit like Earth, but hardly, as NPR's Richard Harris reports, a vacation destination.
RICHARD HARRIS reporting:
Finding new planets is old hat to Geoff Marcy from the University of California at Berkeley, but that doesn't make his latest find boring.
Mr. GEOFF MARCY (University of California at Berkeley): We've announced the discovery of 107 planets, and I think it's fair to say we consider this the most exciting perhaps of all of the 107.
HARRIS: That's because this planet is most like the Earth. It's just twice the diameter of our planet. It's probably made of rock. It orbits a star, Gliese 876, that looks pretty ordinary. True, a year on this planet lasts just two Earth days, but NASA's Jack Lissauer says the planet feels quite a bit like home.
Mr. JACK LISSAUER (NASA): This is likely to be or plausibly the first rocky planet around a normal star other than the sun, and in that sense it's a class of planets like Earth.
HARRIS: It's not exactly a garden spot, though. It's only two million miles from its sun. That means it's hotter than a pizza oven, so don't expect to find any lake-front property there. Now astronomers haven't actually seen this planet, but they can tell it's there by the way its star wobbles. Lissauer says the wobble is influenced by a small nearby object.
Mr. LISSAUER: We believe this discovery of this small planet is a rock-solid discovery, even though the planet itself may or may not be solid rock.
(Soundbite of laughter)
HARRIS: Lissauer and Marcy announced their discovery at a news conference Monday at the National Science Foundation. Richard Harris, NPR News, Washington.