Experts from NASA's Phoenix Mars Lander team have announced recently that they may have just discovered the first evidence of liquid water on the Red Planet. According to pictures sent back by the spacecraft, one of the machine's legs is covered with what appear to be tiny droplets of liquid. Over the weeks that passed since the rover first landed, on the 25th of May, 2008, these formations began to grow in size, and photographs show that a potential cause for this could be the fact that tiny droplets of water that were accumulated during landing may have attracted others from Mars' atmosphere.

In a previous discovery, rovers found out that large amounts of perchlorate salts existed on the planet, which might explain how liquid water formed in sub-zero temperatures. This chemical may keep water flowing just beneath the surface of the planet, but astrophysicists draw attention to the fact that, even if there are large amounts of it underground, it may yet be too salty to support life as we know it.

In March, at the Lunar and Planetary Science Conference in Houston, Texas, members from the team that manages Phoenix, including Nilton Renno from the University of Michigan in Ann Arbor, who has authored a new study, and Peter Smith from the University of Arizona in Tucson, who is the mission's chief scientist, will present a paper detailing the way in which these potential droplets may be attracting water from the atmosphere.

Other 21 team members will co-author the new study, which is already highly-controversial. Nevertheless, scientists hold that there are a number of other pieces of evidence that seem to suggest that liquid water exists on Mars. Among these, the fact that several of the gullies that astronomers hypothesize were shaped by flowing water in the past, have considerably changed their appearance within a matter of years, since humans have started observing them. This hints at the fact that there may yet be aquifers that release bursts of water on occasions beneath the Martian surface.

The study also shows that, while the temperature around Phoenix's landing site never rose above minus 20 degrees Celsius, a mixture of perchlorate salts and water could stay liquid at temperatures as low as minus 70 degrees Celsius. In these circumstances, the salts act as a very powerful anti-freeze, preventing the water from turning instantly into ice.

The clumps of material on Phoenix's “feet” may be water for another reason as well – upon landing, the craft peeled away the top layer of soil with its thrusters, and revealed a layer of ice, from which a portion might have melted on account of the heat. After that, the salts never allowed the water to freeze, and it started accumulating.

If this discovery is confirmed, then we could be witnessing one of the most important finds in the history of astronomy, as where there's water there's always some form of life, or at least the possibility of it developing or having existed in the past.