As a flotilla of Mars-bound probes nears their target, scientists and engineers have begun work on the Mars Phoenix lander, the flagship spacecraft for NASA's Scout line of innovative and econo-class Red Planet explorers.
In some ways, the Phoenix lander is a "been here, nearly done that" type of mission. It's a robotic return to flight of hardware lost when NASA's Mars Polar Lander apparently smashed into the planet's south pole terrain on December 3, 1999. It was never heard from after repeated attempts to make contact.
A follow-on lander was being tested to fly as part of the 2001 Mars Surveyor program, but this work was halted after the failure. That gear was stored in a clean room at Lockheed Martin in Denver in 2000. Phoenix, in effect, was created from the embers of previous missions.