A software error could have caused the lander's braking rockets to shut down prematurely.
Two solar arrays will power the lander through its three-month mission.
None of the landers have found any evidence of life.
Combining both missions involves a single lander and a smaller rover.
The lander came to rest on soil that fills most of the crater.
The non-italicized text is the current picture, based on data from several orbiters and five landers.
The initial results from both landers were very exciting, but also very confusing.
