The coming weekend is an important one in the history of the scientific exploration of Mars. All going well, on May 25 the lander from the Phoenix Mars Mission will land in the northern polar region.
Phoenix is a stationary laboratory designed to study the history of water and search for complex organic molecules. The arctic region has been chosen because there is evidence for large amounts of subsurface water-ice in the northern arctic plains. A robotic arm will dig through the top soil layer and bring both soil and water-ice to the lander platform for analysis.
Despite the absence of surface liquid water there is evidence that water may once have flowed on the Martian surface. Geologic features like gullies and channels could have been formed by surface erosion, or even the movement of subsurface water.
Liquid water is important because all known forms of life require it to survive. So the Phoenix Mars Mission represent an important step in investigating the possibility of life forms on Mars. This is still an open question. Initial investigations during the Viking Mission of the 1970s produced ambiguous results and this and subsequent missions were not capable of subsurface investigations.
We now know that life can exist in the most extreme conditions and it is possible that dormant microbial colonies may be present in the Martian arctic. It’s thought that the soil environment in these areas may have been favourable for life for brief periods every 100,000 years.
Pheonix is an appropriate name for this mission because it is reborn out of fire, like the mythological Phoenix bird. The mission uses many components of the two unsuccessful Mars missions MPL and MSP ’01.
So good luck Phoenix! A successful landing will produce some fascinating new findings.
Rover instrument to sniff out life on Mars
Phoenix Mars Mission
The Phoenix landing site
Phoenix Mars Lander Will Probe for Signs of Life
Here is a neat countdown clock for the Phoenix landing