Stargazer is a Lockheed L-1011 TriStar built in 1974, that was modified in 1994 for use by Orbital Sciences as a mother ship launch pad for the Pegasus launch vehicle. As of October 2022, 45 rockets have been launched from it, using the Pegasus-H and Pegasus-XL configurations. As of 2019, Stargazer is the only L-1011 airframe still airworthy.

Orbital Sciences Corporation was an American company specializing in the design, manufacture, and launch of small- and medium- class space and launch vehicle systems for commercial, military and other government customers. In 2014, Orbital merged with Alliant Techsystems to create a new company called Orbital ATK, Inc., which in turn was purchased by Northrop Grumman in 2018. The remnants of the former Orbital Sciences Corporation became a subsidiary of Northrop Grumman, known as Northrop Grumman Space Systems.