-- Company Scheduled to Deliver its Second Satellite For Thaicom in the First Half of 2016 --

-- THAICOM 8 to Provide Ku-Band Services to Thailand, South Asia and Africa --

DULLES, Va.May 19, 2014-- Orbital Sciences Corporation (NYSE: ORB), one of the world s leading space technology companies, announced today that Thaicom PLC (SET Index: THCOM) has authorized the company to begin the development, manufacturing, integration and testing process for the THAICOM 8 commercial communications satellite. THAICOM 8 will be the second satellite that Orbital will build for Thaicom, following the launch and in-orbit testing and activation of THAICOM 6 in January 2014. THAICOM 8 will join the many GEOStar communications satellite platforms ordered by customers around the world. The new satellite will be produced at Orbital s state-of-the-art satellite manufacturing facility in Dulles, VA.

The THAICOM 8 satellite s payload features 24 active Ku-band transponders to provide services to Thailand, South Asia and Africa. The satellite will generate approximately 5.0 kilowatts of payload power and will be located at 78.5 degrees East Longitude. It is scheduled for completion and launch in the first half of 2016.

Commenting on the start of THAICOM 8 production, Mr. Christopher Richmond, Orbital s Senior Vice President of its Communications Satellites Division, said, We are delighted that Thaicom has joined the ranks of repeat customers for our GEOStar satellite product line. We look forward to executing another very successful program and contributing to their long-term business growth.

Mr. Pramook Chaiwongwutthikul, Thaicom s Senior Vice President for Satellite Engineering and Operation, said, Orbital was an excellent partner on the THAICOM 6 program. We are very pleased to have given Orbital the authorization to begin production of THAICOM 8, which will be the eighth Thaicom satellite. Their GEOStar platform is an ideal match for our requirements in terms of performance, price and schedule, and will help us strengthen our market in Thailand and expand our services in South Asia and Africa.

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 8 kilowatts of payload power. In most instances, the affordable GEOStar satellite can be built and delivered in 24 months or less.

About Thaicom Public Company Limited

Thaicom PLC, established in 1991, has more than 20 years of experience in the satellite business. Thaicom is Asia s leading satellite operator with a unique proposition in providing integrated solutions for satellite broadcast and broadband services. The company has launched six satellites since its inception, including THAICOM 6 (built by Orbital) to provide additional capacity to strengthen Thaicom s Hot Bird position, and also serve the African market under the name Africom-1, and THAICOM 4 (IPSTAR), the world s first broadband satellite providing broadband services to 14 countries across Asia-Pacific. Furthermore, THAICOM 7 will also be launched in 2014 to expand Thaicom s service capabilities and coverage in the regions. For more information, please visit the company s website at www.thaicom.net.

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 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 government agencies and laboratories. More information about Orbital can be found at http://www.orbital.com. Follow the company on Twitter @OrbitalSciences

Source: Orbital Sciences Corporation

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