August 1, 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.
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 canyon.