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


-- New Order Is Company's Second Commercial Satellite Contract in 2011 --

-- Thaicom 6 to Provide Ku- and C-Band Services to South and Southeast Asia and
Southern Africa --

(Dulles, VA 13 June 2011) - Orbital Sciences Corporation (NYSE: ORB) announced today that THAICOM Plc. (SET Index: THCOM) has awarded the company a firm contract for the Thaicom 6 communications satellite. Based on Orbital's GEOStar-2(TM) satellite platform, the Thaicom 6 satellite will be designed, manufactured and tested at Orbital's satellite manufacturing facility in Dulles, VA. The Thaicom 6 satellite is planned to be launched in mid-2013.

Mr. Arak Chonlatanon, THAICOM's Chief Executive Officer, said, "We are pleased that we have signed up with Orbital as the manufacturer of our sixth THAICOM satellite. Orbital is a leading manufacturer of smaller-size satellites, which matched our requirements in terms of performance, price and schedule. Orbital's GEOStar satellite platform will help THAICOM expand its satellite fleet in the Asian region."

The Thaicom 6 satellite's payload will offer hybrid Ku- and C-band services to the South and Southeast Asia and Southern Africa regions. The satellite will generate approximately 3.7 kilowatts of payload power and will be located at 78.5 degrees East Longitude.

Commenting on the new contract award, Mr. Christopher Richmond, Orbital's Senior Vice President of its communications satellite unit, said, "We are very pleased to welcome THAICOM as a new customer for our GEOStar satellite product line. We continue to see excellent adoption of our 'right-size' smaller satellite platform by regional operators around the world, with particular strength in Asia."

The Thaicom 6 satellite is the 34th geosynchronous-Earth orbit communications satellite ordered by Orbital's customers around the world, 23 of which are in orbit with 11 others in design, production or pre-launch preparations. It is Orbital's second order of the year for its commercial communications satellites following the order in February by SES WORLD SKIES for the SES-8 satellite.

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. For example, Orbital and SES WORLD SKIES have already teamed with the U.S. Air Force to deploy the experimental Commercially Hosted Infrared Payload (CHIRP), built by Science Applications International Corporation.

About THAICOM Plc.

THAICOM Plc is a leading satellite and telecommunications operator with customers throughout Asia, Australia, Africa and Europe. Currently the company operates two satellites, Thaicom 4 (iPSTAR), one of the largest communications satellites ever launched, and Thaicom 5. Thaicom 4 delivers broadband services to millions of users across 14 countries in Asia-Pacific. The satellite has a bandwidth capacity of more than 45 gigabits. Established in 1991, the company provides satellite communications and related services, internet-related services and media, as well as telephone services in neighboring countries.

For more information, please visit the company's website at and

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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