After sending between 150,000 and 200,000 commands to the satellite to coax it back into service, Intelsat was forced to scrap its satellite-recovery efforts and to resort, on Monday, to a limited-duration effort to force the satellite to shut down its transponders. This was to be accomplished by sending a stronger series of signals designed to cause Galaxy 15's power system to malfunction and force a shutdown of the satellite's payload.
That attempt, which Luxembourg-based, Washington-headquartered Intelsat had viewed as its last, best-understood option for Galaxy 15, was unsuccessful. With the satellite now nearing AMC-11, Intelsat is limited in what it can do besides assure itself of the satellite's location. "There is no active testing of the payload," the company said in its Tuesday statement.
Sending radio signals strong enough to force a satellite to shut down could pose dangers to other spacecraft in the target area, which is why Intelsat had only a short window of time to "pulse" Galaxy 15 with signals intended to trigger a failure of its power system. That period lasted about 30 minutes on Monday.
"Intelsat fully coordinated with neighboring operators the timing and the effects of this testing to neighboring spacecraft. It is our current understanding that no SES AMC-11 customers were affected by the disabling attempt," Intelsat said.
Intelsat and Luxembourg-based SES have been closely coordinating interference-avoidance options since the initial Galaxy 15 failure, knowing that at predicted drift speeds the satellite will enter AMC-11's 131 degrees west slot to within 0.5 degrees of AMC-11 on or about May 23.
SES officials say they are devising an elaborate series of maneuvers to create a maximum distance between Galaxy 15 and AMC-11 during the period of maximum threat. While they cannot guarantee that there will be no interference to media customers using AMC-11, the SES officials believe they have the resources, including teleport facilities to reroute traffic, required to minimize the problem during this two-week period.