The Space Shuttle Orbiter Endeavour blasts form the launch pad on February 11, 2000 carrying its crew of six for the STS-99 mission, a Shuttle Radar Topography Mission (SRTM), the most ambitious Earth mapping mission to date. Orbiting at 233 kilometers (145 miles) above Earth, two radar anternas, one located in the Shuttle bay and the other located on the end of a 60-meter deployable mast, was used during the mission to map Earth's features. The goal was to provide a 3-dimensional topographic map of the world's surface up to the Arctic and Antarctic Circles. The mission completed 222 hours of around the clock radar mapping gathering enough information to fill more than 20,000 CDs.