The place is inhospitable, with molten temperatures and possibly clouds of melted silicon. But a discovery across the galaxy is giving hope to searchers of intelligent life.
A team led by NASA Ames researchers has confirmed the existence of the first rocky planet outside our solar system. Kepler-10b is closest in size to Earth of 519 extra-solar planets discovered so far. It is about 1 1/2 times the Earth's diameter and speeding around a star similar to our sun in the constellation Cygnus, about 560 light-years away.
"It's unquestionably a rocky world orbiting a star outside our solar system," said Natalie Batalha, deputy science team leader for the Kepler Mission at NASA Ames. She and about 50 other scientists published their discovery Monday in the Astrophysical Journal. Unlike the majority of the so-called exoplanets detected so far, Kepler-10b is solid and not gaseous. "It's something you can stand on," she said.
In September, astronomers led by a University of California at Santa Cruz professor announced they had found what was probably a rocky planet, called Gliese 581g. But other scientists discounted the discovery, pointing to an error in data analysis. So its existence is unconfirmed.
Kepler-10b's discovery is a major dividend paid by NASA Ames' Kepler spacecraft, launched in March 2009.
While Kepler-10b is "in our solar neighborhood," Batalha said, it would be premature to make travel plans. First, its distance from the Earth means that even whizzing there at the speed of light would take 560 years.
The planet's day side is hotter than molten lava, Batalha said. While scientists mine the trove of data, the essential question remains. "We want to know if we're alone in our galaxy," Batalha said. "This is one step in that direction."
San Jose Mercury News