... Mars . ... Observing . ... Opportunity crawls out of Victoria . The Mars rover climbs from the crater after almost a year. ... NASA's Mars Exploration rover Opportunity is heading back out to the Red Planet's surrounding plains nearly a year after descending into a large martian crater to examine exposed ancient rock layers. ... If Opportunity were driving with only five wheels, like Spirit, it probably would never get out of Victoria Crater," says JPL's Bill Nelson, a rover mission manager. ...