Cold and wet: the latest theory about Mars
Wednesday 20 May 2009
Mars may have once been both cold and wet, researchers said today, suggesting a freezing Martian landscape could still have produced water needed to sustain life.
There has been debate over the issue because with some researchers believing water likely formed many features of the planet's landscape and others pointing to evidence indicating that early Mars was cold with temperatures well below the freezing point of water.
Using a computer model, Alberto Fairen of Universidad Autonoma in Madrid and colleagues showed that both could have been possible because fluids containing dissolved minerals would have remained liquid at temperatures well below 273 degrees Kelvin - the freezing point of pure water.
"Our results are compatible with Mars lander and orbiter data and with climate modelling, and suggest a cold and wet early Mars," they wrote in the journal Nature.
The presence of water on Mars is a hot topic for scientists. They have presented strong evidence of huge deposits of frozen water at the Martian poles and point to geological features that indicate large bodies of water have flowed on the planet's surface in the distant past.
Other scientists have said images and computer simulations strongly suggest a landslide of sand and gravel are more likely explanations for the bright deposits in gullies that have been proposed as strong evidence of water flow.
Water is a key to the question of whether life, even in the form of microbes, ever existed on Mars. On Earth, all known forms of life require water.
Feiren and colleagues, including scientists from NASA's Ames Research Center in California, chose compositions based on weathered basalts for the Martian fluids in their model to match the chemical compositions of rock found at Mars landing sites.
This analysis showed that a number of minerals could have lowered the melting point of water in a frozen Martian environment and help explain the early Mars climate paradox, they said.
"The stability against freezing of Martian fluids can explain saline water activity on the surface of Mars at mean global temperatures well below 273 Kelvin," they wrote.
- 1 Kylie Jenner challenge: Bizarre lip suction device inspired by Kardashian sister goes viral
- 2 Rarest Beanie Baby bought for just £10 at car boot sale could be sold for £62,500 on eBay
- 5 Giorgio Armani criticises the way some gay men dress saying 'a man has to be a man'
Rarest Beanie Baby bought for just £10 at car boot sale could be sold for £62,500 on eBay
Katie Hopkins and The Sun editor are reported to police for incitement to racial hatred following migrant boat column
Australian student Tommy Connolly, 23, adopts his pregnant, homeless 17-year-old cousin to give her a chance at 'a better life'
Giorgio Armani criticises the way some gay men dress saying 'a man has to be a man'
Electronic waste worth £34bn piling up in 'toxic mine', warns UN report
If I’m being racially abused I don’t need a stranger with a saviour complex to rescue me
The only black face in the Ukip manifesto is on the page about overseas aid
Ukip is the only main political party to not address LGBT rights in its manifesto
Food banks: One million Britons will soon be using them, according to Trussell Trust
Religion isn't growing, it is becoming vigorous in its demise, says philosopher AC Grayling
BBC election debate: The one photo that summed up the whole 90-minute leaders debate
£14000 - £18000 per annum: Recruitment Genius: An Office Administrator is requ...
£12000 - £40000 per annum: Recruitment Genius: Due to expansion and growth of ...
£40000 - £50000 per annum: Ashdown Group: Senior PHP Developer position with a...
Negotiable: Recruitment Genius: An Operations Leader is required to join a lea...