Last updated at 5:41 PM on 1st August 2011
The idea that there is no water on Mars is something most scientists dare not contemplate for fear of tempting fate.
After all, should the Red Planet have been dry for billions of years then there is zero chance of Nasa's dream of harbouring life there becoming a reality.
But one scientist claims just that - that life on Mars, for mankind at least, will remain a fantasy.
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Evidence of water? The Dao, Niger, and Harmakhis valleys emerge from the flank of the Hecates volcano. A scientist has disputed the generally-accepted theory that the planet's grand canyons were shaped by catastrophic floods
Dr David Leverington, of Texas Tech University, disputes the generally-accepted theory that the planet's grand canyons were shaped by catastrophic floods.
Instead, he tells Inside Science, they were created by low-viscosity lavas as seen in similar channel-like features on the moon and Venus.
Most experts dismiss Dr Leverington's lava theory, insisting that a volume of water greater than the largest rivers on Earth was needed to form these canyons.
But Dr Leverington disputes this: 'The question is: "How do you get that volume of water? How do you move it quickly enough to rush out at a rate to carve channels like these?"'
He also challenges the commonly-held explanation for why there are no giant empty lake beds at the heads of the outflow channels.
Scientists have explained this would-be anomaly by speculating it is the result of extremely porous, permeable ground that was suddenly breached by meteor impacts which cause the movement of hot magma in the Martian crust.
But Dr Leverington said that other researchers have calculated that the permeability of Mars' surface would need to be one to ten million times greater than is likely.
Seabed? Pictures taken by the Mars Odyssey spacecraft and released last month show landforms which scientists believe were created under vast expanses of water
Another sticking point, he claimed, is the location of the starting points of the outflow channels, which tend to commence on the flanks of volcanoes.
Dr Leverington said that this can't be because such huge volumes of water would be more likely from breaches at lower elevations so that there is plenty of 'head' uphill of the breach pushing the water out below.
He also claimed that there are few sediments and minerals that are consistent with Mars being a wet planet.
The vast majority of the minerals found on Mars are not the kind that would survive contact with water and would reform as different minerals if the planet cycled through wet and dry periods.
These minerals would not exist if water was common any time in the near geologic past, he said.
'I would argue that all of these diverse types of data point firmly at volcanic mechanisms.'
But other scientists warn that just because there are some problems with the water theory, there is no reason to dismiss it completely.
Victor Baker, of the University of Arizona's Lunar and Planetary Laboratory, told Inside Science: 'He's reasoning on the features of the moon and Venus when we don't know the causes of those features either.'
'It's very obvious that immense flows of water and lava have been involved,' he added.
Dr Leverington's research will be published in the journal Geomorphology.
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- National Aeronautics and Space Administration
02 Aug, 2011--
Source: http://www.dailymail.co.uk/sciencetech/article-2021196/Life-Mars-No-chance-colonising-Red-Planet-dry-billions-years.html?ITO=1490
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