WASHINGTON — Venezuela’s first and only state-owned communications satellite has been out of service since March 13 when a series of maneuvers left it tumbling in an unusable orbit.
The VeneSat-1 satellite, built by China Great Wall Industry Corp. and launched in late 2008 on a 15-year mission to provide television and broadband services to Venezuela, has been stuck for 10 days in an elliptical orbit above the geostationary arc, according to telescopic observations from two U.S. companies that track satellites.
VeneSat-1’s operator, the Venezuelan space agency ABAE, had issued no status reports on the satellite as of March 23 and could not be reached for comment March 22 or March 23. In January, ABAE said Venezuela and China planned to develop a replacement satellite, VeneSat-2, that would continue service after VeneSat-1 retired.
VeneSat-1 entered service in January 2009, about three months after launching on a Chinese Long March 3B rocket. The satellite was expected to remain in service until at least 2024.
Since geostationary communications satellites typically take two to three years to build, Venezuela could face a coverage gap if it can’t recover VeneSat-1 or use capacity on other satellites covering the region.
“Significant orbit change”
California-based ExoAnalytic Solutions, which operates a network of satellite- and debris-tracking telescopes, spotted a “significant orbit change” for VeneSat-1 on March 13 at 3:15 a.m. Eastern, when the satellite left its position at 78 degrees West longitude over Venezuela, Bill Therien, ExoAnalytic’s vice president of engineering, told SpaceNews. Approximately three hours later, the satellite conducted another maneuver that sent it tumbling westward, he said.
Telescope observations from ExoAnalytic and Pennsylvania-based AGI show VeneSat-1 tumbling in an elliptical orbit that at its lowest point is 50 kilometers above the geosynchronous arc where most large communications satellites reside. Venesat-1’s highest point, or apogee, is roughly 36,300 kilometers — or about 525 kilometers above the geosynchronous arc, according to the companies.
Bob Hall, AGI technical director for space situational awareness, said VeneSat-1 has drifted 30 degrees from its original orbital slot since March 13. If the satellite drifts another 40 degrees, it will be beyond line of sight from Venezuela, complicating any efforts to restore control of the spacecraft unless Venezuela relies on ground stations in other countries.
Collision risk low
When old or ailing geostationary satellites are taken out of service, operators are expected to maneuver them into so-called graveyard orbits typically 300 to 500 kilometers above the geosynchronous belt. At such altitudes, dead satellites should continue to orbit for thousands of years without endangering active satellites.
AGI’s and ExoAnalytic’s observations suggest VeneSat-1’s operators lost contact with the satellite while attempting to move it into a proper, non-elliptical graveyard orbit.
The low point, or perigee, in VeneSat-1’s elliptical orbit, Hall said, may “barely kiss” the notification threshold for operators of satellites in geosynchronous orbit, but is unlikely to cause alarm. The satellite’s apogee is well within graveyard orbit, he said.
Hall noted that operators have been able contact and recover tumbling satellites if they aren’t severely damaged. Most satellites have two omnidirectional antennas on opposite sides to ensure a means of contact, he said.
In 2017, EchoStar and SES both lost contact with ailing satellites but were able to restore contact and safely retire them into graveyard orbit.
SpaceNews Staff Writer Sandra Erwin contributed to this article.
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