Technicians watch the NuSTAR solar array test from inside a clean room environmental enclosure.

With the Pegasus XL rocket and fairing inside Orbital Science's processing facility at Vandenberg Air Force Base in California, technicians watch the NuSTAR solar array test from inside a clean room environmental enclosure.

The Pegasus will launch NASA's Nuclear Spectroscopic Telescope Array NuSTAR into space. After the rocket and spacecraft are processed at Vandenberg, they will be flown on the Orbital Sciences’ L-1011 carrier aircraft to the Ronald Reagan Ballistic Missile Defense Test Site at the Pacific Ocean’s Kwajalein Atoll for launch. The high-energy x-ray telescope will conduct a census for black holes, map radioactive material in young supernovae remnants, and study the origins of cosmic rays and the extreme physics around collapsed stars. For more information, visit science.nasa.gov/missions/nustar/. Photo credit: NASA/Randy Beaudoin, VAFB