spacetoday.net: Russian communications satellite stranded in transfer orbit

Posted: Thu, Aug 18, 2011, 2:13 PM ET (1813 GMT)
Proton-M launch of Express-AM4 (Roscosmos)

A European-built Russian communications satellite, launched Thursday on a Proton rocket, has been stranded in a transfer orbit after the rocket's upper stage malfunctioned. The Proton-M rocket lifted off from the Baikonur Cosmodrome at 5:25 pm EDT Wednesday (2125 GMT Wednesday, 3:25 am local time Thursday) carrying the Express-AM4 satellite for Russian satellite operator RSCC. The satellite was to be released by the Briz-M upper stage after five engine burns, but telemetry from the upper stage was lost after the fourth burn. The cause of the problem and the status of the spacecraft, including whether it may be possible to eventually put the satellite into geosynchronous orbit, are unknown. The satellite, a Eurostar E3000 model built by EADS Astrium, weighed over 5,700 kilograms at launch and carries a payload of C-, Ka-, Ku- and L-band transponders.