COLUMBIA, Md.Oct. 22, 2003--

Company's Integrated GPS Satellite Positioning and Software System to Help Manage and Integrate Two of San Diego's Largest Public Transit Vehicle Fleets

Orbital Sciences Corporation (NYSE:ORB) today announced that its Transportation Management Systems division (Orbital TMS) was recently awarded an $8.4 million contract to supply its ORBCAD communications and dispatch software system in the San Diego, CA area. Orbital TMS was selected by Motorola Inc.'s (NYSE: MOT) Commercial, Government and Industrial Solutions Sector to supply and install in-vehicle components and control center software for the San Diego Metropolitan Transit Development Board's (MTDB) new Regional Transit Management System (RTMS). The RTMS brings together two of San Diego's leading public transit agencies, San Diego Transit Corporation and North County Transit District. Together, the two agencies operate a fleet of 515 public buses and other transit and service vehicles.

Orbital TMS, located in Columbia, Maryland, will install its flexible, easy-to-use ORBCAD communications and dispatch software system to improve MTDB's efficiency in managing and controlling its bus and service vehicle fleet. The RTMS system is designed to track and administer hundreds of vehicles with significant expansion capabilities allowing for the incorporation of other regional transit agencies into its system in the future.

Orbital's system offers full computer assisted dispatch (CAD) capabilities, real-time vehicle tracking via global positioning position (GPS) satellites, wireless data communications, and automated vehicle location (AVL) map and data displays. The system is designed to interface with existing automation systems in the San Diego area, including the Scheduling Software System, the Caltrans District 11 Traffic Management Center, the SANDAG System, the Maintenance System and the Universal Fare System. Orbital will also supply its state-of-the-art in-vehicle components, including the Mobile Data Terminal (SmartMDT) control unit, SmartCount Automatic Passenger Counter System, SmartStop Voice and Visual Annunciation System, and Advanced Traveler Information Systems for MTDB's bus stops.

Mr. Jean Floyd, Orbital's Senior Vice President and General Manager of its TMS division, said, "We are very proud to count 15 of the 20 largest U.S. transit authorities that have deployed AVL systems as our customers. As we have done in the past, we have forged an excellent teaming arrangement with Motorola and welcome the opportunity to work with them again. Together, we will help the MTDB achieve its objective of utilizing technology to increase driver and passenger safety, and to improve overall system operations resulting in superior customer satisfaction."

About Orbital TMS

Orbital TMS is the country's leading supplier of satellite-based Automatic Vehicle Location (AVL) systems for the expanding Intelligent Transportation Systems (ITS) market. Orbital's AVL systems are used by 55 public transit and state agency customers in the U.S. and abroad, with units installed, or scheduled for installation, on approximately 26,000 vehicles.

More information about Orbital TMS can be found at

    CONTACT: Orbital Sciences Corporation
             Public and Investor Relations
             Barron Beneski, 703-406-5528

    SOURCE: Orbital Sciences Corporation