A group led by Geoff Marcy of the University of California, Berkeley announced yesterday at the American Astronomical Society meeting in Honolulu that it had discovered 28 new planets.
The team has expanded on the recent discovery of the "hot ice" planet, GJ 436b, which revolves around GJ 436 (pictured). Marcy said the new data shows that there is a large amount of water on the planet's surface.
"From the density of two grams per cubic centimeter -- twice that of water -- it must be 50 percent rock and about 50 percent water, with perhaps small amounts of hydrogen and helium," Marcy said.
"Now we are very sure it has a rocky core and this giant thick envelope of water," he added.
"This is why we are jumping out of our clothes. It is the first time we have determined the structure of one of these extrasolar planets. It is rocky like Earth but it has a lot of water which is the essential ingredient for life."
Still, the best part of this announcement is that apparently the best exoplanets are yet to come, said UC Berkeley post-doctoral fellow Jason T. Wright, in a statement.
"We're just now getting to the point where, if we were observing our own solar system from afar, we would be seeing Jupiter,"
he said, pointing out that the teams' Doppler technique is now sensitive to stellar wobbles of a meter per second, much less than the
10-meter per second limit they started out with 15 years ago.
Planet-hunters find bonanza of new solar systems [Reuters]
Image credit: Lynette Cook
