The Hindu : Front Page : Water pointers on Mars

Online edition of India's National Newspaper
Friday, Dec 08, 2006
ePaper

Front Page

Front Page

Water pointers on Mars

Seeming photographic evidence from space

Photo: AFP

FLUID PATTERNS: An image released by NASA, showing gullies beneath a small crater on the rim of a larger crater, in September 2005.

LOS ANGELES: Photographs from space suggest that water occasionally flows on the frigid surface of Mars. This raises the tantalising possibility that the Red Planet is hospitable to life, scientists said.

The images, taken by the Mars Global Surveyor of the U.S. National Aeronautics and Space Administration (NASA), and sent before it lost contact with earth, show changes in craters that provide the strongest evidence yet that water coursed through them as recently as several years ago, and is perhaps doing so even now.

"This is a squirting gun for water on Mars," said a scientist at Malin Space Science Systems, which operates a camera on the Surveyor.

The news excited scientists who hunt for extraterrestrial life. If the finding is confirmed, they say, all the ingredients favourable for life on Mars are in place: water and a stable heat source.

In all of its Mars exploration missions, NASA has pursued a "follow the water" strategy to determine if the planet once contained life or could support it now.

Scientists believe ancient Mars was awash with pools of water. And at present-day Mars' north pole, researchers have spotted evidence of water ice. But they have yet to see liquid water."This underscores the importance of searching for life on Mars, either present or past," said an astrobiologist at the University of Colorado at Boulder.

Some researchers were sceptical that liquid water was responsible for the surface feature changes seen by the spacecraft. They said other materials such as sand or dust can flow like a liquid and produce similar results.

"Nothing in the images, no matter how cool they are, proves that the flows were wet, or that they were anything more exciting than avalanches of sand and dust," Allan Treiman, a geologist at the Lunar and Planetary Institute in Houston said. The findings appear in Friday's issue of the journal Science.

The Surveyor spotted tens of thousands of gullies that scientists believed were geologically young and carved by fast-moving water coursing down cliffs and steep crater walls. Scientists decided to retake photos of gullies in a search for evidence of recent water activity.

Two craters in the southern hemisphere that were originally photographed in 1999 and 2001 were examined again in 2004 and 2005, and the images yielded changes consistent with water flowing down the crater walls, according to the study. Scientists said five to 10 pools of water rushed down the craters in each case. — AP

Printer friendly page
Send this article to Friends by E-Mail

Front Page