Posted: Tue, Aug 23, 2011, 6:49 AM ET (1049 GMT)
The Russian space agency announced Tuesday it was suspending launches of the Proton rocket while is investigates why a launch last week stranded a satellite into a transfer orbit. Russian officials said the Express-AM4 satellite launched Thursday is currently in a transfer orbit of 995 by 20,294 kilometers; it was not clear if the satellite was still attached to the Breeze-M upper stage. Officials said they are investigating why the upper stage shut down before completing its series of engine burns to put the satellite into geosynchronous transfer orbit, but suspect the problem is with the upper stage's control system. Engineers are investigating whether the satellite can be transferred to its final orbit. Upcoming Proton launch have been suspended until the cause of the problem is found.