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The Mission

Rocket: Pegasus XL
Payload: C/NOFS
Date: April 16, 2008
Time: 1647-1847 GMT (12:47-2:47 p.m. EDT)
Site: Kwajalein Atoll in Marshall Islands

Pegasus archive

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Video archive

STS-76: In review

The STS-76 astronauts narrate highlights from the 1996 mission that launched Shannon Lucid to the Russian space station Mir.


STS-75: In review

The STS-75 astronauts narrate highlights from the 1996 mission that saw the tethered satellite suddenly break free from the shuttle.


STS-72: In review

The STS-72 astronauts narrate highlights from the 1996 mission that retrieved a Japanese satellite.


STS-122: In review

The STS-122 crew narrates highlights from its mission that delivered Europe's Columbus module to the space station.

 Full presentation
 Mission film

STS-100: In review

The STS-100 astronauts narrate highlights from the April 2001 mission that installed the space station's Canadian robot arm.


STS-102: In review

The STS-102 astronauts narrate highlights from the March 2001 mission that conducted the first ISS resident crew exchange.


STS-123 landing

Shuttle Endeavour returned from space with a night landing March 26 at Kennedy Space Center.


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Satellite launched to forecast communication outages

Posted: April 16, 2008

An experimental Air Force satellite designed to monitor the Earth's ionosphere and foresee impending communication disruptions was successfully deployed into space Wednesday by an Orbital Sciences air-launched Pegasus rocket.

An artist's concept of the C/NOFS satellite deployed in space. Credit: Air Force
An L-1011 carrier jet hauled the winged rocket over the mid-Pacific Ocean at the U.S. Army's Reagan Test Site in the Kwajalein Atoll, then released the booster at approximately 1:01 p.m. EDT (1701 GMT) to begin an eight-minute ascent to orbit.

The three-stage rocket successfully delivered the Communication/Navigation Outage Forecasting System (C/NOFS) spacecraft into an elliptical orbit with a high point of about 525 miles and a low point of 250 miles, with an inclination traveling 13 degrees north and south of the equator.

"Everything went extremely well," Col. Stephen Hargis, director of the DoD Space Test Program, said in a post-launch telephone interview from Kwajalein.

The launch marked the 25th consecutive successful flight for the Pegasus over the past decade.

"Pegasus continues to prove that it is the most reliable and versatile small launcher in the world today, with another successful mission supporting an important Air Force program," said Ron Grabe, Orbital's executive vice president and general manager of its Launch Systems Group.

From its orbit hugging the equator, the C/NOFS satellite and its onboard instruments will measure the space environment to increase warning times for conditions that cause outages of ultra-high frequency (UHF) communications and degrade Global Positioning System navigation signals.

"There's a lot of key areas in the equatorial region that our warfighters have to live and be successful in, and they cannot have a situation where their GPS and UHF comms are going out on them without them knowing it," Hargis said.

"So this system will help improve the forecasting of those outages by approximately four-to-six hours more time."

The disturbances in the ionosphere are called scintillations. C/NOFS will be the first space-based system to predict when such disruptions of critical communications may occur.

"It will help both in an adversarial and defensive way, in also knowing the enemy's comm and navigation could possibly be out due to these scintillations," program manager Capt. Pamela Jessen said from Kwajalein.

"I believe C/NOFS will have a huge impact on the battlefield and help bring more of our troops home alive," Hargis said.

File image of Pegasus rocket launch. Photo: Orbital Sciences
C/NOFS is a joint project of the DoD Space Test Program, Space and Missile Center's Space Development and Test Wing and the Air Force Research Laboratory. General Dynamics built the satellite.

"It is an experiment, so AFRL is going to be running the payload, receiving the data and processing it and passing that to the warfighter," Hargis said.

Controllers plan to spend the next month checking out the satellite before a 12-month data collection mission commences to determine if the satellite instruments can help forecast the onset of the communication outages.

The combined cost of the satellite development and construction, the Pegasus rocket and the 13 months of in-space operations total about $135 million, Hargis said.

It was a long road to get C/NOFS assembled and launched. Original plans called for the craft to fly several years ago.

"The biggest challenge we had a few years back was a solar panel design issue that caused the needing to go back and redesign and rebuild the solar panels. So that slowed down the program," Hargis said.

"The technological challenge on the spacecraft was these instruments are very, very sensitive to RF noise and radiation. So you have to design a satellite that is very, very quiet in terms of RF. That was a big technical challenge of the program. They've overcome everything and it's on-orbit now."

Wednesday's launch was the 39th for the Pegasus rocket and the second to originate from Kwajalein. The mobility of the air-launched booster has enabled Orbital to conduct flights from various sites, including Edwards Air Force Base and Vandenberg Air Force Base in California, Kennedy Space Center and Cape Canaveral Air Force Station in Florida, Wallops Flight Facility in Virginia and Gran Canaria of the Canary Islands off Africa.

The C/NOFS satellite was built in Gilbert, Arizona, then delivered to Vandenberg where it was attached to the Pegasus rocket at Orbital's facilities there. The rocket was mated to the L-1011 aircraft and flown to Kwajalein about 10 days ago.

The far-away Kwajalein location, known for its role as a missile test range, was selected as the launch site because of its proximity to the equator and the targeted orbit for the C/NOFS satellite.

"It takes a couple of days to get here and it's not easy to get in and out of the island. But once you're here, the Reagan Test Site has just been fantastic, everything we needed," Hargis said.

The next scheduled Pegasus mission will use Kwajalein too. A July 15 launch is planned for NASA's Interstellar Boundary Explorer, or IBEX satellite, that will study the interaction between the solar wind and the interstellar medium.