Technicians prepare to attach NASA's Nuclear Spectroscopic Telescope Array or NuSTAR located on the ramp adjacent to the runway on Vandenberg Air Force Base in California.

Technicians prepare to attach NASA’s Nuclear Spectroscopic Telescope Array, or NuSTAR, mated to Orbital Sciences’ Pegasus XL rocket, beneath Orbital’s L-1011 carrier aircraft at the “hot pad,” located on the ramp adjacent to the runway on Vandenberg Air Force Base in California.

The duo will be flown from Vandenberg to the U.S. Army's Ronald Reagan Ballistic Missile Defense Test Site on Kwajalein Atoll, part of the Marshall Islands in the Pacific Ocean. The Pegasus and its NuSTAR payload will be launched June 13 from the carrier aircraft 117 nautical miles south of Kwajalein at latitude 6.75 degrees north of the equator. The high-energy X-ray telescope will conduct a census of 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 http://www.nasa.gov/nustar. Photo credit: NASA/Chris Wiant, VAFB