Commissioned in 1987 to replace the space shuttle Challenger, which was lost in 1986, and named by elementary school students after the British HMS Endeavour, the sailing ship that took Captain James Cook on his first travels, the space shuttle Endeavour has earned a short but noteworthy place in NASA's history of space exploration.
The youngest of NASA's shuttle fleet, Endeavour was built with unique upgrades from previous orbiters, including the drag parachute used on landing; modified electrical and plumbing systems in the Extended Duration Orbiter (EDO), to allow for extended stays on board (up to 28 days); more-advanced computers and navigation systems; a solid-state star tracker; and improved steering mechanisms.
As a tool of space innovation, Endeavour has contributed to projects that have had far-reaching impacts on the space program, including the major Hubble Space Telescope repairs that improved Hubble's clarity, and 10 dockings with the International Space Station, during which Endeavour delivered and installed major sections of the international space outpost. This week will see the launch of mission STS-134, Endeavour's 25th and final flight, and the second-to-last space shuttle mission ever.
In this photo, Endeavour is seen on February 9, 2010, over the South Pacific Ocean off the coast of Southern Chile, at an altitude of 183 miles. The craft is silhouetted against the Earth as it prepares to dock with the International Space Station.
The orange troposphere, where all of the clouds we see from Earth are generated and contained, gives way to the whitish stratosphere and then to the mesosphere.