Eleven Minutes, From Release to Orbit

The Solar Radiation and Climate Experiment (SORCE) satellite was launched Saturday on a Pegasus rocket from Cape Canaveral (FL), carrying four instruments to study and measure solar irradiance, the main source of energy in the Earth's atmosphere. The SORCE satellite is based on Orbital's LEOStar platform.

An Orbital L-1011 aircraft carried the rocket to approximately 40,000 feet over the ocean, where it was released in a horizontal position before igniting its first-stage Orion motor. The composite payload fairing separated ten minutes and 40 seconds into flight, following second-stage ignition. Then, the third-stage Orion motor completed its burn, thrusting the satellite payload into orbit.

The satellite will be fully-tested, and operational, in a matter of days.

The measurements provided by SORCE specifically address long-term climate change, natural variability and enhanced climate prediction, and atmospheric ozone and UV-B radiation. With these measurements, Earth scientists will move a step closer to a full understanding of the Sun's energy output with the launch of the Solar Radiation and Climate Experiment (SORCE) satellite.

Propulsion

ATK's solid fuel Orion rocket motors helped launch the Orbital Sciences Corporation Pegasus® XL vehicle. 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.

ATK Composites is based in Clearfield (UT). 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.

FMI: http://earthobservatory.nasa.gov/Library/SORCE/; www.atk.com