Order Represents Production Units 48 Through 61 Since

                         Beginning of Program

DULLES, Va.Oct. 22, 2007--Orbital Sciences Corporation (NYSE:ORB) was recently awarded a production contract for 13 Coyote supersonic sea-skimming target (SSST) vehicles by the U.S. Navy, the company announced today. The latest order represents a new production contract for the Mach 2.5-capable, low-altitude target used by the Navy to test fleet self-defense systems against a threat-representative target. The total value of the contract is $37.9 million.

The contract was awarded to Orbital by the Naval Air Systems Command (NAVAIR), based at Patuxent River Naval Air Station in Maryland, which manages the Coyote program. This latest contract award represents the company's second full-rate production contract following a highly successful two-year development and flight test program.

Coyote Program Update

Orbital was awarded an initial development contract in 2000 to meet the Navy's requirement for an affordable SSST system to simulate high-speed anti-ship cruise missiles for fleet training and weapon systems research, development, test and evaluation. Orbital and the Navy completed the development phase of the program with six successful test flights, the last of which took place in April 2005.

Since that time, Orbital has received multiple orders from the Navy under low-rate initial production and full rate production contracts. Total orders for the program currently stand at 61 units (including the early development vehicles), of which 19 have either been launched or delivered to the customer.

The Coyote target missile design integrates a four-inlet, solid-fuel ducted-rocket ramjet propulsion system into a compact missile airframe 18 feet long and 14 inches in diameter. Ramjet supersonic takeover speed is achieved using a decommissioned Navy MK 70 solid rocket motor for the first stage. Rail-launched from Navy test and training ranges, the highly maneuverable Coyote achieves cruise speeds of over Mach 2.5 following the separation of the MK 70 first-stage booster. The range of the target vehicle system is approximately 50 nautical miles at altitudes of less than 20 feet above the sea surface.

Orbital is developing and manufacturing the Coyote vehicles at its launch vehicle engineering and production facility in Chandler, Arizona. Orbital's major subcontractors include Aerojet Corporation in Gainesville, Virginia and Sacramento, California, for the solid-fuel ducted-rocket motor, and CEi, Inc. in Sacramento, California, for the vehicle's avionics system.

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


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

    SOURCE: Orbital Sciences Corporation