Rocket to Launch Military Technology Demonstration Payload in 2010

New Order Represents the Eighth Minotaur IV Rocket Under Contract with the U.S. Air Force

Orbital Sciences Corporation (NYSE:ORB) today announced that the U.S. Air Force Space and Missiles Systems Center (SMC) recently placed an order for a new Minotaur IV launch vehicle under the company’s Orbital/Suborbital Program-2 (OSP-2) contract. The order consists of one Minotaur IV launch vehicle that will be used to launch a military technology demonstration payload in 2010. The new order brings the total number of Minotaur launch vehicles procured by the U.S. Air Force, including space launch and target vehicles, to 25 since the inception of the program in 1997. It also represents the eighth Minotaur IV under contract for launches beginning in 2009. The Air Force’s Space Development and Test Wing (SDTW), located at Kirtland AFB, New Mexico, administers the OSP-2 contract. The program office responsible for all Minotaur vehicles is the Launch Test Squadron (LTS) of the SDTW.

Orbital has launched a total of 14 Minotaur vehicles with a perfect mission success record, beginning with the inaugural mission in January 2000. Seven of the missions have been carried out by the Minotaur I space launch vehicle (SLV) configuration and seven by the Minotaur II suborbital target launch vehicle (TLV). Currently, there are 11 Minotaur missions on Orbital’s upcoming launch manifest. These include a Minotaur II TLV vehicle to be launched later this month, a Minotaur I SLV scheduled for a late 2008 flight carrying the U.S. Air Force’s TacSat-3 spacecraft, and the first of eight Minotaur IV rockets, which is scheduled for its inaugural flight in early 2009.

Orbital’s Minotaur vehicles have a history of being used to support technology demonstrations, both for space launch and suborbital missions. The initial Minotaur I SLV mission in 2000 launched a total of 11 spacecraft, including six picosatellites, which are the smallest operational spacecraft ever placed in orbit. This mission was also the first of several Minotaur missions to demonstrate an Orbital-developed GPS Position Beacon that provides autonomous metric tracking, reducing the need for ground-based radars to support launches. In addition, a low-cost TDRSS transmitter flew aboard the Minotaur I COSMIC mission in April 2006, successfully demonstrating over-the-horizon transmission of telemetry data at a greatly reduced cost compared to previous systems.