A U.S. Air Force C-5 Galaxy cargo aircraft part of the Marshall Islands in the Pacific Ocean.

A U.S. Air Force C-5 Galaxy cargo aircraft, foreground, sits on the tarmac at Vandenberg Air Force Base in California as final preparations are under way for the departure of Orbital Sciences’ L-1011 carrier aircraft for the U.S. Army's Ronald Reagan Ballistic Missile Defense Test Site on Kwajalein Atoll, part of the Marshall Islands in the Pacific Ocean. Orbital’s L-1011 is transporting their Pegasus rocket and NASA’s Nuclear Spectroscopic Telescope Array, or NuSTAR, to Kwajalein for launch.

The Pegasus, mated to its NuSTAR payload, will be launched 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. Launch is scheduled for June 13. For more information, visit http://www.nasa.gov/nustar. Photo credit: NASA/Randy Beaudoin, VAFB