sábado, 29 de noviembre de 2008

Water vapour discovered on Saturn's moon

Huge plumes of water vapour and ice particles are bursting out from Saturn's moon Enceladus at supersonic speeds in a way that strongly suggests they come from liquid water down below the icy surface, scientists have said

 Artist's impression of the Cassini spacecraft passing through plumes from geysers that erupt from giant fissures in the moon's southern polar region  Photo: REUTERS
Artist's impression of the Cassini spacecraft passing through plumes from geysers that erupt from giant fissures in the moon's southern polar region Photo: REUTERS

The research, published in the journal Nature, offers new evidence that the moon may harbor an underground ocean of water, meaning conditions might exist that could support life, even if only microbial organisms.

'We think liquid water is necessary for life and there is more evidence that there is liquid water there,' said lead researcher Candice Hansen of NASA's Jet Propulsion Laboratory in Pasadena, California.

'You also need energy, you need nutrients, you need organics. It looks like the pieces are there. Whether or not there's actually life, of course, we can't say.'

Scientists are aware of only three places where liquid water exists near the surface of a planet or other body - Earth, Jupiter's moon Europa and now Enceladus.

In July Nasa’s Phoenix Mars Lander confirmed the presence of ice on Mars.

The previous month the spacecraft uncovered a bright white layer just two inches below the surface, which disappeared four days after it was exposed to sunlight, leading scientists to believe it was ice.

After examining a soil sample from a trench approximately two inches deep, the claim was confirmed.

In a Nasa statement, William Boynton of the University of Arizona said: “We have water.

“We’ve seen evidence for this water ice before in observations by the Mars Odyssey orbiter and in disappearing chunks observed by Phoenix last month, but this is the first time Martian water has been touched and tasted.”

Phoenix principal investigator Peter Smith, of the University of Arizona, said: “Mars is giving us some surprises.

“We’re excited because surprises are where discoveries come from.”

Scientists will now begin asking whether the frozen water could have been liquid at some point in the planet’s history, which would have created an environment in which life could have evolved.

Experts believe that if life ever existed on Mars, it could still survive today in isolated pockets beneath the soil.

source: telegraph.co.uk