Workers monitor NASA's NuSTAR as it is lowered onto a handling dolly.

In the airlock at Vandenberg Air Force Base.

In the airlock at Vandenberg Air Force Base.

The Pegasus rocket in which NuSTAR will be launched.

Computer graphic of what the NuSTAR satellite would look like, fully extended.

Enclosed in an environmentally controlled shipping container, NuSTAR arrives at Vandenberg Air Force Base in California. Credit: NASA

NuSTAR begins the journey to the launch pad.  Credit: OSC.

The integrated NuSTAR observatory at Orbital Sciences Corporation in January 2012.  Credit: OSC.

The integrated NuSTAR observatory at Orbital Sciences Corporation in January 2012.  Credit: OSC.

NuSTAR promotional sticker.

The integrated NuSTAR observatory at Orbital Sciences Corporation in June 2011.

The integrated NuSTAR observatory at Orbital Sciences Corporation in June 2011.

Artist's concept of NuSTAR on orbit.

Artist's concept of NuSTAR on orbit.

NuSTAR instrument at JPL on April 19, 2011. The instrument shipped to Orbital on April 23rd.

Final pre-launch mast deployment, in December 2010 at ATK-Goleta.

Assembly of the first NuSTAR optics module was completed on August 5th at Columbia University’s Nevis Laboratory. In reflection: Todd Decker.

The first NuSTAR optics module at Columbia University on 2010 May 16, showing 82 of the eventual 133 layers.

NuSTAR's extendable mast, built by ATK-Goleta, during deployment testing in August 2009.

NuSTAR's extendable mast, built by ATK-Goleta, during deployment testing in August 2009.