Satellite Placed in Orbit Despite Heater Problem

A new weather satellite was locked into stationary orbit above the Atlantic Ocean on Friday by a motor fired one day early because of a heater problem.

“The firing went fine; there were no problems,” said Larry Heacock, director of the National Oceanic and Atmospheric Administration’s satellite operations center.

The $55-million GOES-7 satellite was launched Thursday by a Delta rocket. The on-board motor was triggered Friday by a radio command from a ground station when the satellite neared its high point in orbit.

The firing placed the satellite in stationary orbit at 22,237 miles high. At that altitude, a spacecraft travels at the same speed as the rotation of the Earth and thus hovers over one spot on the globe.

GOES-7, which stands for geo-stationary operational environmental satellite, will join a sister satellite, GOES-6, to keep an eye on weather patterns in a wide area ranging from the mid-Pacific to the eastern Atlantic and including all of the United States.

Heacock said that soon after the launching, trackers detected that the motor that would kick GOES-7 into stationary orbit was overheating, apparently because of a faulty thermostat on a heater.

“We switched to the backup heater, but it started to run off, too,” he said. “The solution was to control the temperature by watching it and turning the heater on when necessary.”

Because this required constant attention, he said, the decision was made to ignite the motor a day earlier than planned.