English: A Delta II launch vehicle carrying the X-ray Timing Explorer (XTE) lights up the sky at 8:48 a.m. EST, December 30, 1995. Liftoff occurred from Launch Complex 17, Pad A, on Cape Canaveral Air Station under the management of a combined government/contractor launch team that includes NASA, the Air Force and McDonnell Douglas. The XTE spacecraft is outfitted with three scientific instruments that will study X-rays, including their origin and emission mechanisms, and the physical conditions and evolution of X-ray sources within the Milky Way galaxy and beyond. The XTE is one is a series of Explorer missions planned by NASA; it will perform its observations from a vantage point in low Earth orbit for a mission duration expected to last two to five years. The Delta II 7920 expendable launch vehicle carrying the XTE spacecraft into orbit is provided by McDonnell Douglas. Delta 230, as this vehicle was designated, is the first in the Delta family to fly outfitted with a new advanced avionics system.