So once our tank, I mean, scientific vehicle lands on the Pole, it will be sniffing around to try and find signs of water in either frozen or liquid form, and also if life could have ever been sustained ere
Heres the offical line :
The complement of the Phoenix spacecraft and its scientific instruments are ideally suited to uncover clues to the geologic history and biological potential of the Martian arctic. Phoenix will be the first mission to return data from either polar region providing an important contribution to the overall Mars science strategy "Follow the Water" and will be instrumental in achieving the four science goals of NASA's long-term Mars Exploration Program.
They forgot to mention the machine guns and high explosives, but thats ok. We dont want the Martians finding out anyway.
Heres a vid explaining what has to happen to get the Phoenix onto the martian surface without doing an impression of the Dambusters bouncing bomb.