At Astrotech Space Operations in Titusville Fla. workers guide the STEREO spacecraft toward the upper stage booster.

At Astrotech Space Operations in Titusville, Fla., workers guide the STEREO spacecraft toward the upper stage booster in the background. The spacecraft will be mated to the upper stage and then transported to Launch Pad 17-B at Cape Canaveral Air Force Station for integration with the Delta II already on the pad. STEREO stands for Solar Terrestrial Relations Observatory and comprises two spacecraft. The STEREO mission is the first to take measurements of the sun and solar wind in 3-dimension. This new view will improve our understanding of space weather and its impact on the Earth. STEREO is expected to lift off Aug. 31. Photo credit: NASA/George Shelton