DULLES, Va.Sept. 18, 2006--Orbital Sciences Corporation (NYSE:ORB) announced today that four of its executives are being promoted to new positions within the company. Mr. G. David Low, currently Vice President and head of the company's Technical Services Division (TSD), is being promoted to Senior Vice President and Program Manager for the Commercial Orbital Transportation Services (COTS) program. Replacing Mr. Low at the helm of TSD will be Mr. John Pullen, an 18-year veteran of the division. Mr. Gregg Burgess, Program Manager of Orbital's MiTEx satellite program, is being advanced to Vice President of Special Programs, and Ms. Sally Richardson, who most recently served in the company's Advanced Programs Group, is being promoted to the position of Vice President and Deputy Director of Technical Operations, overseeing the engineering activities at the company's facilities in the Eastern United States.

G. David Low

Mr. Low has been with Orbital for 10 years and has served in various roles with the company, including leading the Launch Systems Group's successful ISO certification effort and its quality and mission assurance function. Most recently, he headed Orbital's TSD, which provides engineering services and subsystem design and manufacturing to U.S. government customers. In his new role, Mr. Low will oversee the company's development, manufacturing, testing and operational activities related to Rocketplane Kistler's (RpK) K-1 reusable launch vehicle, which was recently selected by NASA for the COTS award. Orbital is RpK's primary industrial partner on the COTS program.

Gregg Burgess

Mr. Burgess is assuming the leadership of the Special Programs business area in Orbital's Advanced Programs Group. The Special Programs business area specializes in developing new space-based capabilities using advanced technologies on aggressive schedules to meet emerging national security space mission requirements. In this capacity, he will be assuring the continued success of ongoing programs and expanding Orbital's business base in this area. Mr. Burgess is transitioning from his role as Program Manager of the MiTEx satellite program, which Orbital designed and built for the Defense Advance Research Projects Agency (DARPA), a position he has held for the last three years. Mr. Burgess' 14 years at Orbital has spanned technical, business development and program management roles in aircraft, space transportation and satellite systems.

John Pullen

Mr. Pullen has been with Orbital for the past 18 years at TSD. For the past two years, he has acted as Mr. Low's deputy head of the division, which is based in Greenbelt, MD. He is a trained electrical engineer with broad familiarity with the company's current customers and of the overall market for TSD's services. Mr. Jack Danko, who, until recently, was head of the Space Systems Group, Orbital's largest business unit, will serve as an advisor to Mr. Pullen on a part-time basis.

Sally Richardson

Ms. Richardson is assuming new responsibilities as Vice President and Deputy Director of Technical Operations - East. She will be responsible for overseeing the engineering standards, policies and procedures of all programs being carried out at Orbital's Dulles, VA campus, including the new Orion crew exploration vehicle, numerous commercial communications and government satellites, and new reusable launch vehicle initiatives. Ms. Richardson's previous role as Senior Director of Orbital's Advanced Programs Group included the planning and design of the Orion Launch Abort System, Program Manager for NASA's Orbital Space Plane program and Deputy Program Manager for NASA's X-34 reusable launch vehicle program. She is a 14-year veteran of Orbital, having joined the company in 1992. Ms. Richardson will report to Mr. David Hastman, Vice President of Technical Operations - East.

About Orbital

Orbital develops and manufactures small space and rocket systems for commercial, military and civil government customers. The company's primary products are satellites and launch vehicles, including low-orbit, geosynchronous-orbit and planetary spacecraft for communications, remote sensing, scientific and defense missions; ground- and air-launched rockets that deliver satellites into orbit; and missile defense systems 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.

Note to Editors: Photos of Mr. Low, Mr. Burgess, Mr. Pullen and Ms. Richardson are available on Orbital's web site at: http://www.orbital.com/About/ExecutiveProfiles/profile.html


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

    SOURCE: Orbital Sciences Corporation