DULLES, Va., June 27 /PRNewswire/ -- Orbital Sciences Corporation (NYSE: ORB) announced today that its MacDonald, Dettwiler and Associates Ltd. (MDA) subsidiary was recently awarded two new contracts for its space robotics systems from the Canadian Space Agency (CSA) and the National Aeronautics and Space Administration (NASA). With a total value of about $65 million, these contracts are for ongoing engineering services and logistics support to ensure the appropriate functioning of MDA's space robotics systems, which are an important part of many Space Shuttle missions and will play a critical role in the assembly and operations of the International Space Station (ISS).

The CSA contract, valued at approximately $50 million over three years, provides for technical operations, sustaining engineering and logistics support for the Mobile Servicing System (MSS), Canada's primary contribution to the ISS. The contract will encompass MDA's ground processing, launch and in-orbit operations support activities. The MSS, which will include the next- generation "Canadarm," will continue to service and maintain the ISS, following the assembly process, for 15 to 20 years.

The NASA contract, valued at approximately $15 million over two years, provides for engineering services for MDA's robotic workstation that will be installed aboard the ISS. This robotic workstation allows an astronaut to operate the MSS from the safety of the ISS and avoid the risks to humans posed by extravehicular space walks.

Orbital's MDA subsidiary is Canada's leading space and information systems company and is the world's primary supplier of space robotics technology. It employs approximately 1,700 people at major facilities in the Vancouver and Toronto areas, as well as at other Canadian and international locations.

Orbital is one of the largest space technology and satellite services companies in the world, with 1999 total enterprise revenues (including revenues from unconsolidated affiliates) of approximately $915 million. The company, headquartered in Dulles, Virginia, employs about 5,500 people at major facilities in the United States, Canada and several overseas locations.

Orbital is the world's leading manufacturer of low-cost space systems, including satellites, launch vehicles, electronics and sensors, satellite ground systems and related digital infrastructure. Its Magellan subsidiary is a pioneer in satellite-based navigation and communications products for consumer and industrial markets. Through its ORBCOMM and ORBIMAGE affiliates and ORBNAV subsidiary, Orbital is also a major operator of satellite-based networks that provide data communications, high-resolution imagery and automotive information services to customers all around the world. SOURCE Orbital Sciences Corporation

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CONTACT: Barron Beneski of Orbital Sciences Corporation, 703-406-5000 or Beneski.barron@orbital.com/