Newspaper article The Christian Science Monitor

Sixth Rock from Jupiter May Be Hospitable to Life Photos of Jupiter's Frozen Moon Hint at Liquid Subsurface

Newspaper article The Christian Science Monitor

Sixth Rock from Jupiter May Be Hospitable to Life Photos of Jupiter's Frozen Moon Hint at Liquid Subsurface

Article excerpt

If a potato-sized meteorite from Mars has sparked fresh speculation about organic life elsewhere in the solar system, a moon orbiting Jupiter may well add fuel to the fire.

Fresh images of the icy surface of Jupiter's satellite Europa, taken by the Galileo spacecraft in July, give hints that the Jovian moon could host an environment capable of supporting primitive forms of life.

One of the key requirements for such organisms is water. Europa long has been known to have a surface encrusted in a layer of ice up to 60 miles thick. But the shots from Galileo detailed Tuesday at a briefing at NASA's Jet Propulsion Laboratory in Pasadena, Calif., show surface features that resemble ice flows in the polar seas on Earth, geysers, and crustal ridges where new material may be welling up from beneath the satellite's surface.

Whole plates and sheets seem to have rotated intact, suggesting that they are riding on a layer of slush or water, says Ronald Greeley, one of the Galileo project's imaging scientists and a geologist at Arizona State University. This implies the existence of a heat source driving Europa's frost-bound equivalent of plate tectonics. The heat comes from the impact of tidal forces on the moon, with Jupiter's gravity tugging from one direction and the gravity from two other large moons, Ganymede and Callisto, tugging from another.

When researchers consider likely targets in space as candidates for biological research, they look for water, the presence of organic materials, and sufficient heat to support life. "The things we're seeing in the pictures, these mobile zones, are places that could be environmentally favorable for life," Dr. Greeley says.

The images of Europa, taken as Galileo passed within 96,000 miles of the moon on July 27, cover an area of the surface roughly equal in size to the United States west of the Mississippi River. They have allowed researchers to pinpoint details "not even suspected" from pictures returned in 1979 from the Voyager. …

Search by... Author
Show... All Results Primary Sources Peer-reviewed

Oops!

An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.