The last five Mars landings by NASA have been successful, but the landing method being used for the Phoenix mission has not been used in 32 years, and the spacecraft that was the model for Phoenix disappeared when it attempted to land in 1999.
Overall, 55% of landing attempts on Mars failed, leading to a lot of anxiety as the May 25 landing date for Phoenix approaches. [right: artist's impression of Phoenix Mars Lander. Credit: NASA]
Peter Smith at the University of Arizona is the lead scientist on the project.