The U.S. Air Force's newest secure communications satellite is nearly halfway through a yearlong orbit-raising process devised after one of its thrusters failed shortly after the spacecraft reached its initial orbit, the service announced Feb. 10. The Advanced Extremely High Frequency (AEHF)-l satellite, built by Lockheed Martin Space Systems of Sunnyvale, Calif., was successfully launched Aug. 14 into a highly elliptical orbit ranging from 230 kilometers above Earth at perigee to 50,000 kilometers above Earth at apogee. The satellite was designed to use its hydrazine-fueled liquid apogee engine to raise its perigee to 19,000 kilometers over 30 days, and then use its xenon-ion electric thrusters to circularize its orbit at 36,000 kilometers over 90 days.
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