For Immediate Release
For More Information Contact:

Barron Beneski (703) 406-5528
Public and Investor Relations
beneski.barron@orbital.com

ORBITAL-BUILT STAR ONE C3 COMMUNICATIONS SATELLITE SUCCESSFULLY LAUNCHED

-- Company's GEOStar Satellite Operating As Expected Early In Its 16-Year Mission --

(Dulles, VA 12 November 2012) -- Orbital Sciences Corporation (NYSE: ORB), one of the world's leading space technology companies, today announced the Star One C3 communications satellite, built by the company for Star One S.A., was successfully launched into orbit on Saturday, November 10 aboard an Ariane 5 rocket from Kourou, French Guiana. Over the next several weeks, Orbital will work with Star One's engineering team to conduct in-orbit testing to verify all the spacecraft systems are functioning properly before it is officially turned over to Star One for full operational control and commencement of commercial service.

"We are early in the initial check-out and testing process and the Star One C3 mission is proceeding smoothly," said Mr. Christopher Richmond, Orbital's Senior Vice President of Communications Satellite Programs. "This is the first GEOStar satellite we have built for Star One and we are proud to be a part of their team, helping increase communications capacity to meet the rapidly growing demand for telecommunications services in Latin America."

About the Star One C3 Satellite

Orbital designed, built and tested the Star One C3 satellite in Dulles, VA at its satellite manufacturing and test facility. It incorporates a hybrid payload comprised of 28 active C-band transponders for coverage of South America, and 16 x 72 MHz Ku-band transponders with six switchable channels between Brazil and the Andean coverage region. The spacecraft, based on Orbital's flight-proven GEOStarTM platform, will generate approximately 5.0 kilowatts of electrical payload power. The Star One C3 satellite is designed and fueled for a service life of 16 years. Its geosynchronous location will be at 75 degrees West longitude, and is also capable of operating from 84 degrees West longitude if required.

About Orbital's GEOStar Satellite Platform

Orbital's highly successful communications satellites are based on the company's GEOStar satellite platform, which is able to accommodate all types of commercial communications payloads. The GEOStar design is optimized for satellite missions requiring up to 7.5 kilowatts of payload power. In most instances, the affordable GEOStar satellite can be built and delivered in 24 months or less. The GEOStar platform can also host separate government-sponsored payloads that take advantage of the satellite's spare mass, power and communications capacity, as well as its quick launch schedule and demonstrated record of in-orbit reliability.

About Star One

Star One is the leading satellite operator in Latin America. It is a Brazilian company, wholly owned by Embratel. The company was created in 2000 and operates five GEO satellites (Star One C1, C2, C3 and C12 and Brasilsat B4), and two satellites in inclined orbital (Brasilsat B2 and B3), six of which are operated from its teleport, located in Guaratiba (RJ). Star One C3, together with C1, C2 and C12, are the third and newest generation of satellites of the company. The capacity of those satellites supports a complete range of solutions for customers in the segments of telephony, TV, pay-TV, data and corporate networks. For more information, please visit www.starone.com.br

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 http://www.orbital.com.

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Note to editors: A high-resolution photograph of the Star One C3 satellite in Orbital's Dulles, VA manufacturing facility is available at: http://www.orbital.com/NewsInfo/ImagesMultimedia/Images/SatelliteSpaceSystems/index.shtml


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