Venezuela’s flagship communications satellite out of service and tumbling

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 from other satellites. 

“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 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 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 continue to orbit for thousands of years without endangering active satellites. 

Hall said the low point, or perigee, in VeneSat-1’s orbit may “barely kiss” the notification threshold for operators of satellites in geosynchronous orbit, but is unlikely to cause alarm. Its apogee is well within graveyard orbit, he said.

Hall said operators can 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. 

EchoStar and SES, for example, both lost contact with satellites in 2017 but were able to restore communications with the drifting satellites and retire them into graveyard orbit. 

SpaceNews Staff Writer Sandra Erwin contributed to this article. 

source: spacenews.com