First liquid water may have been spotted on Mars
NASA's Phoenix lander may have captured the first images of liquid water on Mars - droplets that apparently splashed onto the spacecraft's leg during landing, according to some members of the Phoenix team.
The controversial observation could be explained by the mission's previous discovery of perchlorate salts in the soil, since the salts can keep water liquid at sub-zero temperatures. Researchers say this antifreeze effect makes it possible for liquid water to be widespread just below the surface of Mars, but point out that even if it is there, it may be too salty to support life as we know it.
A few days after Phoenix landed on 25 May 2008, it sent back an image showing mysterious splotches of material attached to one of its legs. Strangely, the splotches grew in size over the next few weeks, and Phoenix scientists have been debating the origin of the objects ever since.
One intriguing possibility is that they were droplets of salty water that grew by absorbing water vapour from the atmosphere. Arguments for this idea are laid out in a study by Phoenix team member Nilton Renno of the University of Michigan in Ann Arbor, and co-authored by 21 other researchers, including the mission's chief scientist, Peter Smith of the University of Arizona in Tucson. The study (pdf) will be presented in March at the Lunar and Planetary Science Conference in Houston, Texas.
The controversial observation could be explained by the mission's previous discovery of perchlorate salts in the soil, since the salts can keep water liquid at sub-zero temperatures. Researchers say this antifreeze effect makes it possible for liquid water to be widespread just below the surface of Mars, but point out that even if it is there, it may be too salty to support life as we know it.
A few days after Phoenix landed on 25 May 2008, it sent back an image showing mysterious splotches of material attached to one of its legs. Strangely, the splotches grew in size over the next few weeks, and Phoenix scientists have been debating the origin of the objects ever since.
One intriguing possibility is that they were droplets of salty water that grew by absorbing water vapour from the atmosphere. Arguments for this idea are laid out in a study by Phoenix team member Nilton Renno of the University of Michigan in Ann Arbor, and co-authored by 21 other researchers, including the mission's chief scientist, Peter Smith of the University of Arizona in Tucson. The study (pdf) will be presented in March at the Lunar and Planetary Science Conference in Houston, Texas.
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