(02/10/2000) -- After the rollback of the Rotating Service Structure on Launch Pad 39A, Space Shuttle Endeavour is marked with shadows from the lights on the Fixed Service Structure. Above the orange external tank is the Gaseous Oxygen Vent Hood, often called the 'beanie cap,' waiting to be lowered. The hood helps vent gaseous oxygen vapors away from the Space Shuttle until launch, when it is raised and retracted two and a half minutes before liftoff. Endeavour waits for mission STS-99, known as the Shuttle Radar Topography Mission (SRTM), which will chart a new course to produce unrivaled 3-D images of the Earth's surface. The result of the SRTM could be close to 1 trillion measurements of the Earth's topography. The mission is expected to last 11days, with Endeavour landing at KSC Tuesday, Feb. 22, at 4:36 p.m. EST. This is the 97th Shuttle flight and 14th for Shuttle Endeavour