— Mr. Williams Brings Over 20 Years of Corporate Finance Experience to
Company

Mr. Michael R. Williams has been named
Senior Vice President and Treasurer of Orbital Sciences Corporation (NYSE:
ORB),
one of the world’s leading providers of commercial and government space
systems,
the company announced today. Mr. Williams’s background includes over 20
years
of banking experience with Bank of America in senior level positions. At
Orbital, he will oversee the company’s banking relationships and treasury
functions, as well as have responsibility for capital markets, treasury
management, insurance, foreign exchange and real estate activities.

Mr. Garrett E. Pierce, Orbital’s Executive Vice President and Chief
Financial
Officer, said “We are very pleased that Mike Williams has joined our
management
team. Mike’s extensive background in structuring and executing financial
transactions will be a major asset for the company.”

Prior to joining Orbital, Mr. Williams spent substantially all his career
with
Bank of America (formerly NationsBank), most recently serving as a Managing
Director in Global Corporate and Investment Banking. He holds a Bachelor of
Science degree in Business Administration from the University of Maryland
and an
MBA in Finance from the University of Michigan.

Orbital develops and manufactures affordable space systems, including
satellites, launch vehicles, electronics and advanced space systems.
Orbital is
also involved with satellite-based networks that provide wireless data
communications and high-resolution Earth imagery to customers around the
world.