English: A Boeing Delta II 7425 expendable launch vehicle lifts off with NASA's Mars Climate Orbiter at 1:45:51 p.m. EST, on Dec. 11, 1998, from Launch Complex 17A, Cape Canaveral Air Station. The launch was delayed one day when personnel detected a battery-related software problem in the spacecraft. The problem was corrected and the launch was rescheduled for the next day. The first of a pair of spacecraft to be launched in the Mars Surveyor '98 Project, the orbiter is heading for Mars where it will first provide support to its companion Mars Polar Lander spacecraft, which is planned for launch on Jan. 3, 1999. The orbiter's instruments will then monitor the Martian atmosphere and image the planet's surface on a daily basis for one Martian year (1.8 Earth years). It will observe the appearance and movement of atmospheric dust and water vapor, as well as characterize seasonal changes on the surface. The detailed images of the surface features will provide important clues to the planet's early climate history and give scientists more information about possible liquid water reserves beneath the surface.