DULLES, Va., April 30 /PRNewswire-FirstCall/ -- Orbital Sciences Corporation (NYSE: ORB) 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

SOURCE  Orbital Sciences Corporation
    -0-                             04/30/2003
    /CONTACT:  Barron Beneski, Public and Investor Relations of Orbital
Sciences Corporation, +1-703-406-5528, or Beneski.barron@orbital.com/
    /Web site:  http://www.orbital.com/

CO:  Orbital Sciences Corporation
ST:  Maryland, Virginia

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3213 04/30/2003 14:08 EDT http://www.prnewswire.com