NASA's Quick Scatterometer (QuikScat) was lofted into space at 7:15 p.m. Pacific Daylight Time today atop a U.S. Air Force Titan II launch vehicle from Space Launch Complex 4 West at California's Vandenberg Air Force Base. The satellite was launched in a south-southwesterly direction, soaring over the Pacific Ocean at sunset as it ascended into space to achieve an initial elliptical orbit with a maximum altitude of about 800 kilometers (500 miles) above Earth's surface.
Approximately two and a half minutes after launch, as the spacecraft sailed over the ocean, past the coast of Mexico's Baja, California peninsula, the Titan II first-stage engine shut down and the second stage was ignited. A minute later, the fairing or nose cone separated in two halves and was jettisoned as planned, followed two minutes later by second-stage engine shut-down. Sixteen seconds later, the Titan rocket turned to reorient itself and shield the QuikScat satellite from sunlight.
The Titan launch vehicle and QuikScat spacecraft then coasted over the southern hemisphere for 48 minutes, crossing Antarctica and heading in a north-northwesterly direction toward Africa. Over Madagascar, when the Titan reached maximum altitude, its second-stage thrusters were fired to adjust the vehicle's orbit.
Just off the coast from Mozambique, about 59 minutes after launch, the QuikScat satellite separated from the Titan II's second stage booster and was pushed into a looping orbit over Earth's poles that will bring it as close as 279 kilometers (173 miles) from Earth's surface and as far away as 807 kilometers (501 miles). An hour into flight, QuikScat deployed its solar arrays. A tracking station at Svalbard, Norway, acquired the first signal from the spacecraft at 8:32:50 p.m. PDT, or about 1 hour and 18 minutes after launch.
During the next two weeks, QuikScat will fire its thrusters as many as 25 times to circularize and gradually fine-tune its polar orbit. Thruster firings will be carried out in up to five clusters of five burns apiece. During each cluster, the thrusters will fire for 10 minutes, then will rest for two orbits, then will fire again for 10 minutes until a total of five burns are performed. The clusters will be spaced two days apart.
Eighteen days into flight, the scatterometer science instrument on QuikScat will be turned on for the first time. Members of the project engineering and science teams will spend the next 12 days performing detailed checks of the instrument and initially calibrating its radar backscatter and ocean wind measurements. Although calibration and validation of the measurements will continue for several months, QuikScat will formally begin its primary mission of mapping ocean wind speed and direction starting about 30 days after launch. The primary mission is scheduled to continue for two years.
QuikScat is managed for NASA's Office of Earth Science, Washington, DC, by the Jet Propulsion Laboratory, which also built the scatterometer instrument and will provide ground science processing systems. NASA's Goddard Space Flight Center, Greenbelt, MD, managed development of the satellite, designed and built by Ball Aerospace & Technologies Corp., Boulder, CO. NASA's Earth Sciences Enterprise is a long-term research and technology program designed to examine Earth's land, oceans, atmosphere, ice and life as a total integrated system. JPL is a division of the California Institute of Technology, Pasadena, CA.
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