KENNEDY SPACE CENTER, FLA. -- At Astrotech Space Operations in Titusville, Fla., a worker attaches a high pressure line on the THEMIS spacecraft in preparation for fueling, which is scheduled for Jan. 3-5. THEMIS consists of five identical probes, the largest number of scientific satellites ever launched into orbit aboard a single rocket. This unique constellation of satellites will resolve the tantalizing mystery of what causes the spectacular sudden brightening of the aurora borealis and aurora australis - the fiery skies over the Earth's northern and southern polar regions. THEMIS is scheduled to launch Feb. 15 from Cape Canaveral Air Force Station. Photo credit: NASA/George Shelton KSC-06pd2849