For Immediate Release

For More Information Contact:
Barron Beneski (703) 406-5528
Public and Investor Relations


-- Satellite is the First of Four GEO Communications Satellites Slated for Launch in 2011 --

(Dulles, VA 25 April 2011) -- Orbital Sciences Corporation (NYSE: ORB), one of the world's leading space technology companies, announced today that the Intelsat New Dawn satellite, built by the company for Intelsat S.A. and Convergence Partners of South Africa, was successfully launched into geosynchronous transfer orbit aboard an Ariane 5 rocket originating from Kourou, French Guiana. The mission began on Friday, April 22 with the lift-off of the Ariane 5 space launch vehicle at 5:37 p.m. (EDT). The satellite successfully separated from the Ariane rocket's final stage approximately 35 minutes after launch.

Orbital designed, built and tested the Intelsat New Dawn spacecraft at the company's satellite production and test facility in Dulles, VA. The spacecraft features a hybrid payload consisting of 16 active Ku-band and 14 active C-band transponders. Following a several week in-orbit check-out period, Intelsat New Dawn will be transitioned to its permanent orbital slot at 32.8 degrees East Longitude to provide voice, wireless backhaul, internet and media applications to its coverage areas in Africa, the Middle East and Europe. The spacecraft will provide approximately 5.0 kilowatts of payload power and is designed for a 15-year on-orbit mission life.

Mr. Christopher Richmond, Orbital's Senior Vice President, said, "We are very pleased with the early results of the mission following another successful launch by Arianespace. The Intelsat New Dawn satellite is the latest Orbital-built spacecraft to join Intelsat's fleet. In total, Intelsat has ordered 10 Orbital STAR satellites, with the IS-18 and IS-23 satellites currently in the production and test phases of their development."

About Orbital

Orbital develops and manufactures small- and medium-class rockets and space systems for commercial, military and civil government customers. The company's primary products are satellites and launch vehicles, including low-Earth orbit, geosynchronous-Earth orbit and planetary exploration spacecraft for communications, remote sensing, scientific and defense missions; human-rated space systems for Earth-orbit, lunar and other missions; ground- and air-launched rockets that deliver satellites into orbit; and missile defense systems that are used as interceptor and target vehicles. Orbital also provides satellite subsystems and space-related technical services to U.S. Government agencies and laboratories.

More information about Orbital can be found at

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