For Immediate Release
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Barron Beneski (703) 406-5528
Public and Investor Relations



-- Over the Last 18 Months Company's Technical Services Division Has Supported 26 Suborbital Rocket Launches from Five Locations Around the World
Under NSROC II Contract --

(Dulles, VA 28 March 2012) - Orbital Sciences Corporation (NYSE: ORB), one of the world's leading space technology companies, today congratulated NASA on the successful launch of five sounding rockets in a stream of launches that took place in less than seven minutes for the Anomalous Transport Rocket Experiment (ATREX) program. All five launches took place from NASA's Wallops Flight Facility (WFF) in Virginia and were supported by Orbital's Technical Services Division (TSD), which serves as the prime contractor on the NASA Sounding Rocket Operations Contract II (NSROC II). Orbital TSD worked in conjunction with NASA's Sounding Rocket Program Office and other WFF operations for launch and mission operations. Each of the five rockets were built and tested by Orbital TSD for this unique mission.

The first rocket was launched at 4:58 a.m. (EDT) on March 27, 2012. Each subsequent rocket was launched 80 seconds apart and released a chemical tracer that created milky white clouds at the edge of space. The ATREX program is part of a study to better understand the processes responsible for the high-altitude jet stream located 60 to 65 miles above the surface of the Earth.

"We are proud to be a major contributor to this important science mission," said Mr. John Pullen, Orbital Senior Vice President of the company's Technical Services Division. "ATREX was a very ambitious undertaking and the program's entire team did a great job in bringing it across the finish line. We look forward to successfully executing future suborbital missions and continue to be excited with our role as a partner with NASA's Sounding Rocket Program Office."

The five-rocket ATREX mission brings to 26 the total number of launches the Orbital TSD team has supported since the beginning of the NSROC II contract in October 2010. These missions have been carried out from geographically distant launch ranges, including Wallops Island, VA, White Sands Missile Range, NM, Poker Flat, AK, San Nicolas Island, CA, and Andoya, Norway.

About Orbital

Orbital develops and manufactures small- and medium-class rockets and space systems for commercial, military and civil government customers. The company's primary products are satellites and launch vehicles, including low-Earth orbit, geosynchronous-Earth orbit and planetary exploration spacecraft for communications, remote sensing, scientific and defense missions; human-rated space systems for Earth-orbit, lunar and other 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 provides satellite subsystems and space-related technical services to U.S. Government agencies and laboratories.

More information about Orbital can be found at

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