- Third Direct-Broadcast Satellite in BSAT-2 Series in Final
             Preparations for June Launch Aboard Ariane Rocket -

           - Orbital Readies Satellite for Delivery to Launch Site
                  In About 17 Months After Contract Award -

DULLES, Va., May 15 /PRNewswire-FirstCall/ -- Orbital Sciences Corporation (NYSE: ORB) announced today that the company-built BSAT-2c geostationary (GEO) communications satellite has been shipped to the space launch complex in Kourou, French Guiana, where it is scheduled to be launched aboard an Ariane 5 rocket in mid-June. The BSAT-2c satellite is the third direct-broadcast television spacecraft Orbital has manufactured for Japan's Broadcasting Satellite System Corporation (B-SAT). The Ku-band satellite was successfully built and tested at Orbital's state-of-the-art satellite production facility in Dulles, VA in just over 17 months following contract award, a new record for the company's STAR small GEO satellite platform.

"We are very pleased to respond to the needs of one of our most valued customers with a responsive, 17-month satellite manufacturing program," said Dr. Ali Atia, President of Orbital's GEO communications satellite unit. "We are looking forward to the on-orbit delivery of BSAT-2c, which will enhance the reliability and capacity of the BSAT network, of which the Orbital-built BSAT-2a satellite has been a part since 2001."

Over the next several weeks, a team of engineers from B-SAT, Arianespace and Orbital will work together to integrate the satellite with the launch vehicle and perform an extensive series of tests and inspections to ensure that the combined systems of the satellite and rocket are working properly.

In the past several years, Orbital has developed a strong niche position in the world market for GEO communications satellites. With its ramp-up in the production of small, lighter-weight satellites, the company is on track to replicate its decade-long success following the introduction of its small- sized Pegasus(R) and Taurus(R) rockets to the world launch vehicle market in the early 1990's.

Orbital's GEO satellites are based on the company's STAR family of smaller GEO satellite platforms, which are able to accommodate most types of commercial communications payloads. For many applications, the STAR design is an attractive alternative to the larger, more costly GEO satellites offered by the industry's traditional suppliers.

The STAR satellites are smaller and are significantly less expensive to manufacture and launch. They are a perfect fit for customers in the early stages of building their business or established companies that wish to replace or add capacity to their network.

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

Note to Editors:

A high-resolution image of a BSAT-2 satellite is available on Orbital's web site at: http://www.orbital.com/NewsInfo/Images/GEO

     Contact:
     Barron Beneski (703) 406-5528
     Public and Investor Relations
     Beneski.barron@orbital.com 
SOURCE  Orbital Sciences Corporation
    -0-                             05/15/2003
    /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 http://www.orbital.com/NewsInfo/Images/GEO/
    (ORB)

CO:  Orbital Sciences Corporation; Arianespace; Broadcasting Satellite System
     Corporation; B-SAT
ST:  Virginia, Japan
IN:  ARO
SU:


JV-JA 
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8418 05/15/2003 10:12 EDT http://www.prnewswire.com