Earthlike planets may be common

If life on Earth did indeed spring forth within our vast oceans, then it also might be teeming on thousands of other worlds. New models suggest that as many as one-third of the solar systems in the galactic neighborhood might contain terrestrial planets with oceans of water that could harbor life.

The new findings counter previous hypotheses on planetary formation, which have claimed that few solar systems contain Earth-like worlds. Part of the problem has to do with so-called hot Jupiters. These gas giants, which orbit closer to their parent stars than Mercury does to the sun, form relatively quickly from the gas in the protoplanetary disk. Astronomers assumed that as these hot Jupiters plow through disk material, they "vacuum up" a lot of the dust and rock or eject it from the solar system. That would leave little material left with which to make water-logged planets, reports Science Now.

The team from Colorado, Penn State University and NASA's Goddard Space Flight Center Maryland ran computer simulations of various types of solar systems forming.

The gas giants may help rocky planets form close to the suns, and may help pull in icy bodies that deliver water to the young planets, they found.

"These gas giants cause quite a ruckus," Raymond said.

Water is key to life as humans define it.

"I think there are definitely habitable planets out there," Raymond said. "But any life on these planets could be very different from ours. There are a lot of evolutionary steps in between the formation of such planets in other systems and the presence of life forms looking back at us."

As many as 40 percent of the 200 or so known planets around other stars are Hot Jupiters, the researchers said, informs Reuters.