A productive year for the Delta rocket program that launched spacecraft to observe Earth, dig up frozen water on Mars and explore uncharted worlds in the asteroid belt was capped with a successful ascent of a modernized GPS navigation satellite on Thursday afternoon from Cape Canaveral.

Credit: Chris Miller/Spaceflight Now SEE MORE LAUNCH IMAGES HERE

The year's finale began at 3:04 p.m. EST as the Delta 2 booster darted away from pad 17A carrying the newest craft for the Global Positioning System.

The three-stage launcher propelled the 4,500-pound satellite into a highly elliptical orbit reaching about 11,000 miles at the high point, 100 miles at the lowest and inclined 40 degrees to the equator. The Lockheed Martin-made satellite was released from the spent rocket 68 minutes after liftoff.

"The Delta 2 and GPS team did great work throughout this launch campaign," said Col. James Planeaux, Air Force mission director for the launch and commander of the Delta Group. "I'm thrilled to see those long hours and dedication to the mission rewarded with a pinpoint orbit insertion for GPS 2R-18."

A solid-propellant kick motor on the satellite itself will fire in a few days to circularize its orbit at 11,000 miles and increase the inclination to 55 degrees where the GPS constellation flies. The craft should be ready to enter service within a couple of weeks.

"The successful deployment of this high-performance satellite represents another important milestone in the modernization of the GPS constellation and reflects our commitment to achieving mission success for our customer," said Don DeGryse, Lockheed Martin's vice president of Navigation Systems. "Our team is now focused on performing a rapid and efficient on-orbit checkout to quickly place the satellite's advanced navigational capabilities into operational service."

Controllers will maneuver the $75 million craft into the Plane C, Slot 1 position of the constellation to take the place of GPS 2A-24. That satellite then moves into another role replacing the ailing GPS 2A-20 satellite, which was launched in May 1993 and has long outlived its seven-year design life.

The orbiting network emits continuous navigation signals that allow users to find their position in latitude, longitude and altitude and determine time.

Credit: Chris Miller/Spaceflight Now SEE MORE LAUNCH IMAGES HERE

The GPS 2R-18 spacecraft is the fifth in a series of eight with enhanced features designed to rejuvenate the GPS constellation.

"Today's launch moves us another step closer to modernizing the vital GPS constellation, which provides combat effects our warfighters depend on," said Brig. Gen. Susan Helms, commander of the Cape's 45th Space Wing.

The modernized satellites transmit additional signals and feature improvements aimed at greater accuracy, tougher resistance to interference and better performance for users around the world.

The new civilian signal removes navigation errors caused by the Earth's ionosphere. The military advancements will provide an enhanced jam-resistant signal and enable more-precise targeting of GPS-guided weapons in hostile environments.

"We have the most robust and capable Global Positioning System in the history of space, and we are focused on delivering world-class space-based positioning, navigation and timing capabilities for our military and civil communities. Thanks to the men and women of the 45th and 50th Space Wings, our industry partners and the Delta 2 and (GPS) 2R launch teams, the success of today's launch was possible due to their dedication and hard work," said Col. David Madden, commander of the Space and Missile Systems Center's Global Positioning Systems Wing.

Nine Delta rockets soared to space in 2007, all delivering their NASA, U.S. military and commercial cargos without fault.

"This launch wraps up a high-tempo year of delivering space capability to our nation, including three Delta launches from Cape Canaveral in the last 64 days. It's a great year-end exclamation point for the Launch and Range Systems Wing, the United Launch Alliance, and all of our mission teammates," said Planeaux.

The highlights from 2007:

• The Phoenix lander was dispatched for Mars to examine the frozen water in the northern plains that could be a habitable zone for life.
• NASA's Dawn space probe powered by exotic ion engines was launched to orbit the worlds of Vesta and Ceres in the heart of the asteroid belt.
• Five tiny NASA satellites for the THEMIS mission were put in orbit to uncover the physics behind Earth's auroras.
• Two launches of modernized replacement satellites were carried out to reinvigorate the Global Positioning System.
• A pair of Italian-made COSMO-SkyMed satellites that use radar to image the Earth for commercial and military uses were lofted in separate launches.
• The Delta 2 rocket marked its 75th consecutive successful launch with deployment of the sharp-eyed WorldView 1 Earth-imaging spacecraft.
• And the mammoth Delta 4-Heavy rocket entered operational service with the launch of the Air Force's final Defense Support Program missile warning satellite.

Complete coverage all nine launches, plus the missions from the past several years can be found in our Delta archive.

Additional coverage for subscribers:
VIDEO: THE DELTA 2 ROCKET BLASTS OFF WITH GPS 2R-18 PLAY
VIDEO: MOBILE SERVICE TOWER IS ROLLED BACK FOR LAUNCH PLAY
VIDEO: GPS SATELLITE ANIMATION PLAY
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