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Powerful communications satellite feared lost in space BY STEPHEN CLARK SPACEFLIGHT NOW Posted: August 17, 2011 Updated: Aug. 18 Russia lost contact with a Breeze M upper stage and a powerful communications satellite Thursday, hours after the duo blasted off from Kazakhstan on a Proton rocket.
"Four of the five Breeze M burns were performed within the prescribed timeframes," Roscosmos, the Russian space agency, said in a press release. "In the time interval between the fourth and fifth burns there occurred irregularities in telemetry data downlinking and reception of signals from both the Breeze M and the [spacecraft]." After lifting off from the Baikonur Cosmodrome in Kazakhstan at 2125 GMT (5:25 p.m. EDT), the 19-story Proton rocket streaked into space trailing orange and blue flames from six main engines. After reaching the upper atmosphere in less than two minutes, the Proton shut down its first stage and ignited its second stage main engine to continue thrusting toward orbit. The Proton's third stage finished its burn less than 10 minutes after liftoff, leaving the rocket's Breeze M upper stage to ignite and inject itself into a low-altitude parking orbit. Four more Breeze M upper stage engine firings were planned to inject the 12,731-pound Express AM4 communications satellite in an elliptical geosynchronous transfer orbit. But something went wrong before the single-engine Breeze M stage was supposed deploy Express AM4. Spacecraft separation was expected at 0638 GMT (2:38 a.m. EDT). Roscosmos reported engineers lost contact with the Breeze M rocket between the fourth and fifth burns. Roscosmos later released an update saying they discovered the Breeze M upper stage in orbit, but they didn't say whether it had released Express AM4 as planned or if it was in the correct orbit. The report also didn't say if Express AM4 was located. The space agency launched an inquiry to look into the anomaly. The U.S. Air Force is tracking a single object from the launch in an orbit ranging from an altitude of 91 miles to more than 7,000 miles. The object could be an auxiliary fuel tank jettisoned as planned by the Breeze M stage between its third and fourth ignitions. Proton rockets and Breeze rocket stages also launch commercial communications for International Launch Services, or ILS, a U.S.-based firm that sells the Russian launcher to the global marketplace. A Breeze stage last failed in February during the launch of a Russian military research satellite, but that mishap involved another version of the rocket stage. The most recent Proton launch succumbing to a Breeze M failure was in 2008, when the commercial U.S. AMC 14 communications satellite was stranded in an unusable orbit on an ILS-sponsored commercial mission.
The Express AM4 spacecraft, built by EADS Astrium, was designed to provide communications coverage over Russia and neighboring countries for the next 15 years. The satellite was to be operated by the Russian Satellite Communications Co., the country's state civil satellite operator. RSCC's satellite fleet beams presidential and government communications services, federal television and radio signals, direct-to-home television, broadband Internet, and facilitates VSAT and corporate networks. Express AM4's own propulsion system was supposed to circularize its orbit 22,300 miles over the equator in the next few days. The craft's operational station was planned to be at 80 degrees east longitude, placing its communications payload in range of almost all of Russia's territory. The spacecraft was based on Astrium's Eurostar E3000 satellite platform. Express AM4 was the largest Express satellite ever ordered by Russia and the most powerful satellite ever built in Europe with 16 kilowatts of electrical generation capability, according to Astrium. The platform carried 63 transponders in C-band, Ku-band, Ka-band and L-band. Its 12 communications antennas were expected to reach a swath of the globe stretching across Russia from the Pacific Ocean to Eastern Europe. Khrunichev arranged Express AM4's construction contract with Astrium and was responsible for delivering the satellite in orbit for RSCC. Khrunichev is the prime contractor for the Proton rocket. |
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