WASHINGTON — DirecTV’s Spaceway-1 satellite, which suffered a battery malfunction last month that could still cause it to explode, is moving out of geostationary orbit and away from other satellites, ground-based observations show.
Spaceway-1 began relocating Jan. 29, two satellite trackers told SpaceNews, and is continuing to raise its altitude to a “graveyard orbit” about 300 kilometers above active geostationary communications satellites.
As of Friday morning, Spaceway-1 was about 100 to 120 kilometers above the geosynchronous arc and drifting west about 1.4 degrees per day, according to Bill Therien, vice president of engineering at ExoAnalytic Solutions, a Foothill Ranch, California-based company that operates a network of more than 300 telescopes that monitor satellites and objects in space.
Spaceway-1 moved 60-80 kilometers Thursday, and was drifting at a rate of 0.9 degrees to the west, Therien said.
Satellite position data called Two-Line Elements, or TLEs, show Spaceway-1 began moving Jan. 29 at about 2:00 a.m. Eastern, according to Jonathan McDowell, an astronomer at the Harvard-Smithsonian Center for Astrophysics who tracks satellite movements.
Spaceway-1 a 15-year-old satellite three years past its design life, suffered a battery malfunction in December and cannot be safely recharged.
DirecTV on Jan. 19 told the U.S. Federal Communications Commission that the company needs to decommission Spaceway-1 by Feb. 25 to avoid the risk of an explosion that could pose a threat to other satellites in the vicinity.
Spaceway-1 is currently relying on power generated directly by its solar arrays, but that will no longer be possible starting Feb. 25 when the satellite’s orbit starts regularly crossing Earth’s shadow beginning an extended period of brief eclipses that require the use of battery power. McDowell said these so-called eclipse seasons occur twice a year for geosynchronous satellites, and last about six weeks.
DirecTV is a subsidiary of AT&T, and operates a fleet of satellites for television broadcasting. Spaceway-1 was being used as a backup satellite prior to last month’s malfunction, according to Jim Kimberly, a spokesman for the company. Kimberly declined to say how long it would take to complete Spaceway-1’s relocation.
In its Jan. 19 filing, DirecTV told the FCC that the accelerated disposal operation means Spaceway-1 will not be able to dump all of its remaining fuel before the satellite is permanently powered down. Venting fuel is a safety measure meant to decrease the risk of a decommissioned satellite eventually exploding.
Boeing, the satellite’s manufacturer, said similar satellites have a low risk of repeating the same malfunction, but that the company was providing other operators with a “minor update to operating procedures” to avoid a similar malfunction.
