Contract Modification From Lockheed Martin Continues Company’s Decade-Long Role in Supporting In-Orbit Servicing Of Groundbreaking Space-Based Observatory

Orbital Sciences Corporation
announced today that its Technical Services Division, based in
Greenbelt, MD, has been awarded a two-year $22 million cost reimbursable
contract from Lockheed Martin Corporation for engineering support services for
NASA’s upcoming Hubble Space Telescope (HST) servicing mission. This recent
award continues the company’s involvement in HST servicing missions over the
past 10 years. The fifth servicing mission of the orbiting observatory is
currently scheduled to take place in 2004 following earlier missions in 1993,
1997, 1999 and 2002. Orbital has contributed to each of the four previous
missions, with responsibility for the design, integration and testing of the
Space Support Equipment, which ensures that the HST’s new scientific
instruments and orbital replacement units are safely transported aboard the
Space Shuttle.

Under the contract, which Orbital will carry out at NASA’s Goddard Space
Flight Center and Kennedy Space Center, the company will develop payload
integration hardware for the Space Shuttle and provide engineering support for
actual mission operations. For the upcoming HST servicing mission, Orbital is
developing a new lightweight composite carrier unit to maximize the payload
capacity of the Shuttle, increasing the amount of hardware that can be
installed into the space-based telescope.

“Orbital’s continued involvement in the Hubble Space Telescope servicing
missions is a real source of pride for all Orbital employees,” said Mr.
Richard Hicks, Orbital’s Vice President and head of its Technical Services
Division. “To play a role in maintaining one of man’s greatest accomplishments
in space is a very rewarding experience. We look forward to offering our
continued support to Lockheed Martin and NASA in the next servicing mission of
this marvelous observatory,” Mr. Hicks concluded.

Orbital is one of the world’s leading developers and manufacturers of
affordable space systems for commercial, civil government and military
customers. The company’s primary products include low-orbit, geostationary and
planetary spacecraft for communications, scientific and remote sensing
missions; ground- and air-launched rockets that deliver satellites into orbit;
and missile defense boosters that are used as target and interceptor vehicles.
Orbital also offers space-related technical services to government agencies
and develops and builds satellite-based transportation management systems for
public transit and public works agencies, as well as private vehicle fleet

More information about Orbital can be found at:

CONTACT: Barron Beneski, Public and Investor Relations, of Orbital
Sciences Corporation, +1-703-406-5528, or