Solid propulsion Orion
rocket motors produced by ATK (Alliant Techsystems) helped launch
an Orbital Sciences Corporation Pegasus® XL vehicle on Jan. 25
that placed into orbit a NASA solar research satellite.

ATK Thiokol Propulsion, Promontory, Utah, manufactures the Orion motors at
its production facility in Magna, Utah. The motors, which provide power for
all three stages of the air-launched Pegasus XL rocket, have flown on the
vehicle since its first mission in 1990.

The composite payload fairing, filament-wound solid rocket motor cases,
and interstage, which form the Pegasus vehicle’s main structure, are produced
by ATK Composites, Clearfield, Utah.

The Solar Radiation and Climate Experiment (SORCE) satellite launched by
the Pegasus rocket from Cape Canaveral Air Force Station, Fla. carries four
instruments to study and measure solar irradiance, the main source of energy
in the Earth’s atmosphere. The measurements provided by the satellite will
address long-term climate change, natural variability and enhanced climate
prediction, and atmospheric ozone and UV-B radiation.

Since its maiden flight in 1990, Orbital’s Pegasus rocket has conducted 32
missions and launched more than 70 satellites — becoming the world’s standard
for affordable and reliable small launch vehicles. An Orbital L-1011 aircraft
carries the rocket to approximately 40,000 feet over the ocean, where it is
released in a horizontal position before igniting its first-stage Orion motor.
The composite payload fairing separates approximately 110 seconds into flight,
following second-stage ignition. Approximately ten minutes into the flight,
the third-stage Orion motor completes its burn, thrusting the satellite
payload into orbit.

ATK Thiokol Propulsion is the world’s leading supplier of solid-propellant
rocket motors. Products manufactured by the company include propulsion
systems for the Delta, Pegasus, Taurus®, Athena, Atlas, H-IIA, and Titan IV
B expendable space launch vehicles, NASA’s Space Shuttle, the Trident II Fleet
Ballistic Missile and the Minuteman III Intercontinental Ballistic Missile,
and ground-based missile defense interceptors.

ATK Composites — the largest producer of filament-wound and fiber-placed
structures in the U.S. — has revolutionized the composites industry through
40 years of innovation and manufacturing excellence. The company produces
structures for space launch vehicles, satellites, spacecraft, and commercial
and military aircraft.

ATK is a $2.1 billion aerospace and defense company with leading positions
in propulsion, composite structures, munitions, and precision capabilities.
The company, which is headquartered in Edina, Minn., employs approximately
12,000 people and has three business groups: Aerospace, Precision Systems,
and Ammunition. ATK news and information can be found at www.atk.com .