jueves, 27 de marzo de 2008

Saturn's Moon of Enceladus Has `Recipe for Life'

Saturn's Moon of Enceladus Has `Recipe for Life,' NASA Says

By Alex Morales

March 27 (Bloomberg) -- Saturn's moon Enceladus has a ``surprising organic brew,'' containing most of the ingredients needed for life, erupting in geysers from beneath its surface and spewing into the atmosphere, NASA said.

Instruments aboard the U.S. National Aeronautics and Space Administration's Cassini spacecraft revealed a concentration of water vapor, carbon dioxide, carbon monoxide and organic material 20 times denser than expected, the agency said in an e-mailed statement. Temperatures were also higher than previously noted.

``Enceladus has got warmth, water and organic chemicals, some of the essential building blocks needed for life,'' Dennis Matson, Cassini project scientist at NASA's Jet Propulsion Laboratory in Pasadena, California, said in the statement. ``We have quite a recipe for life on our hands, but we have yet to find the final ingredient, liquid water.''

Saturn's moons have long been of interest to scientists, who say the largest, Titan, may resemble an early version of Earth, providing clues to how the planet developed. Enceladus, the sixth-largest moon, had already surprised scientists when in 2005 they detected a ``significant atmosphere.''

The latest findings also revealed that Enceladus's chemical components resemble those found in comets, raising questions about the formation of Saturn, Hunter Waite, principal investigator for one of Cassini's instruments, said in the statement, without elaborating.

Cassini also measured temperatures near the south pole of Enceladus of minus 93 degrees Celsius (minus 135 Fahrenheit), about 17 degrees warmer than previously measured in the region.

Liquid Water

``The surprisingly high temperatures make it more likely that there's liquid water not far below the surface,'' John Spencer, another project scientist, said in the statement, e- mailed yesterday. ``These spectacular new data will really help us understand what powers the geysers.''

Enceladus, with a diameter of 499 kilometers (310 miles), lies some 238,020 kilometers from the ringed planet. The moon is one of the most reflective objects in the solar system, bouncing back nearly all visible light that hits it.

Cassini was launched from Cape Canaveral, Florida, in 1997, bearing the Huygens probe. The craft traveled more than 2.2 billion miles before entering orbit around Saturn in 2004. In January 2005, Huygens was sent down through Titan's atmosphere, gathering data on the moon's physical, chemical and electrical properties.

Cassini has continued to orbit Saturn, beaming back information on the ringed planet and its moons. The $3.2 billion Cassini-Huygens mission is a collaboration between NASA, the European Space Agency and the Italian Space Agency.

Source bloomberg.com