Orbital Sciences
Corporation announced today that Dr. Edward F. Crawley, Professor
and Head of the Aeronautics and Astronautics Department at M.I.T., has been
appointed to the company’s Board of Directors. He replaces Dr. Jack L.
Kerrebrock, also of M.I.T., who retired from the Board at this year’s annual
meeting of shareholders after 19 years as a company Director.

“We are very happy to welcome Ed to Orbital’s Board. His broad experience
and deep technical knowledge will be of tremendous benefit to the company in
our space and defense business,” said Mr. David W. Thompson, Chairman and
Chief Executive Officer. “We also want to express our great gratitude to
Jack, whose intellectual leadership and wise judgment have helped guide
Orbital’s growth during the last two decades,” Mr. Thompson added.

In addition to his teaching, research and administration duties at M.I.T.,
Dr. Crawley also leads the M.I.T./Cambridge University Cooperative Institute,
is a member of the National Academy of Engineering and the NASA Advisory
Council, and is a Fellow of the American Institute of Aeronautics and
Astronautics. He is the author of over 50 technical publications and is an
active pilot, including recognition as a recent U.S. regional soaring
champion. Dr. Crawley holds B.S., M.S., and Ph.D. degrees in aeronautics and
astronautics from M.I.T.

Orbital develops and manufactures small space systems for commercial,
civil government and military customers. The company’s primary products are
spacecraft and launch vehicles, including low-orbit, geostationary and
planetary spacecraft for communications, remote sensing and scientific
missions; ground- and air-launched rockets that deliver satellites into orbit;
and missile defense boosters that are used as interceptor and target vehicles.
Orbital also offers space-related technical services to government agencies
and develops and builds satellite-based transportation management systems for
public transit agencies and private vehicle fleet operators.

More information about Orbital can be found at http://www.orbital.com

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