Orbital Sciences Corporation was an American company specializing in the design, manufacture and launch of small- and medium- class space and rocket 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 today are a subsidiary of Northrop Grumman known as Northrop Grumman Space Systems.
Orbital was headquartered in Dulles, Virginia and publicly traded on the New York Stock Exchange with the ticker symbol ORB. Orbital's primary products were satellites and launch vehicles, including low-Earth orbit, geosynchronous-Earth orbit and planetary spacecraft for communications, remote sensing, scientific and defense missions; ground- and air-launched rockets that delivered satellites into orbit; missile defense systems that were used as interceptor and target vehicles; and human-rated space systems for Earth-orbit, lunar and other missions. Orbital also provided satellite subsystems and space-related technical services to government agencies and laboratories.
On April 29, 2014, Orbital Sciences announced that it would merge with Alliant Techsystems to create a new company called Orbital ATK, Inc. The merger was completed on February 9, 2015 and Orbital Sciences ceased to exist as an independent entity.