Ham radio satellite survives 'close encounter'

AMSAT-NA VP Operations, Drew KO4MA, received notification from the US Joint Space Operations Center, located at Vandenberg Air Force Base, California on Sunday, February 28 warning that amateur radio satellite AO-51 would have a close approach to another satellite, FORMOSAT 3-D, on Monday at 1056 UTC.

This occurred over the Eastern US, with many stations on hand capable of receiving telemetry from AO-51 before and after the near miss.

Drew said, "The predicted miss distance was 953 meters, which is over 3000 feet overall but the radial difference between the two orbits was only 39 meters."

Steve, W3HF noted, "Given the orbital uncertanties of both satellites, an orbit separated by only 39 meters could mean that distance may become eaten up rather quickly!"

In preparation for the close encounter, Drew shut off the S band tran- smitter and turned on the digital downlink at 2 watts, with telemetry transmitted every 5 seconds. The next morning, on March 1, Drew was able to post a message that AO-51 was alive and well, "It looks like we are fine. A second warning email this morning from the Air Force called it even closer, but everything was working at LOS this pass."

FORMOSAT-3 is a constellation of satellites launched on April 15, 2006. It is a joint U.S.-Taiwanese project with major participants including the University Corporation for Atmospheric Research (UCAR), the National Science Foundation, the Naval Research Laboratory (NRL), the Air Force Research Laboratory (AFRL) on the U.S. side and the National Space Organization (NSPO) on the Taiwanese side.

Source: ANS, Drew KO4MA, and Steve, W3HF