CHANDLER, Ariz.March 11, 2005--Orbital Sciences Corporation (NYSE:ORB), one of the fastest growing larger companies in the Chandler area, today announced that it has received two job training grants, totaling over $300,000, from the Arizona Department of Commerce. The grants will be used to help train the company's rapidly expanding workforce in Chandler. Since 2000, Orbital has doubled its local workforce, currently employing about 1,200 full- and part-time employees and contract workers at its Chandler facility. The announcement of the training grant awards was made yesterday during a meeting of the Chandler City Council and was attended by numerous local and state officials. Mr. James Utter, Orbital's Senior Vice President and Deputy General Manager of the company's Launch Systems Group, accepted the training grant awards on behalf of the company.

Commenting on the training grant awards, Mr. Utter said, "We are very appreciative of the outstanding support the State of Arizona offers to the business community to help stimulate job training and employment growth in the high-tech aerospace industry. We are looking forward to enhancing our active training programs that enable our employees to continue to develop their technical skills in this very competitive business environment."

Mr. Joe Yuhas, Deputy Director of the Arizona Department of Commerce, said, "The Arizona Job Training Program is driven by the needs of business. This program allows both the employer and the employees to acquire the job specific knowledge they need."

The Arizona Job Training Program supports the design and delivery of training plans that meet unique industry standards and challenges. The Arizona Department of Commerce works with companies that need resources to upgrade skills of existing employees or to train new hires. Businesses can apply for grants and receive up to 75 percent of the costs of training net new employees and up to 50 percent of costs of training existing employees. Approved on-the-job training costs can be reimbursed up to 25 percent.

For more information on the Arizona Job Training Program visit the Arizona Department of Commerce website at

About Orbital

Orbital is one of the world's leading designers and manufacturers of launch vehicles and satellites that are used by U.S. government customers, including military and civil agencies and commercial enterprises. Orbital's facility in Chandler is the company's primary center for the design, engineering, testing and light manufacturing of a wide variety of suborbital rockets primarily used to test missile defense systems and for space launch vehicles that are used to place small- to medium-class satellites into low-altitude orbits. Orbital specializes in the design and production of smaller sized, more affordable space systems as compared to the much larger, more expensive systems supplied by the "giants" of the aerospace industry.

For more information about Orbital, visit the company's web site at:

Note to Editors: High-resolution aerial photographs of Orbital's Chandler, AZ facility and many of the launch vehicle products that are designed and developed at the location are available on the company's web site at:

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

    SOURCE: Orbital Sciences Corporation