Friday, June 30, 2017

Signals from Saturn… and a Satellite Rescue

Artist's conception of Cassini spacecraft in orbit around
Saturn (NASA image)
The ARRL Letter reports that British ham Paul Marsh, M0EYT, has successfully received signals transmitted by the Cassini spacecraft from its current orbit of Saturn. Cassini was launched in 1997 and serves as an orbiting repeater for the European Space Agency's Huygens probe, which is transmitting from the surface of Saturn's moon Titan. According to the report, Cassini is currently making about two dozen dives through Saturn's rings and is expected to crash into the planet in September. Marsh monitored the 8.4-GHz signals with a 2.4-meter dish and a homebrew downconverter.

A ham in Australia is being credited with rescuing a satellite built by three universities in his country and launched as part of the European QB50 project. According to the AMSAT News Service, the I-Inspire-2 cubesat was successfully deployed from the International Space Station in May, but did not appear to come on the air. Engineers determined that the most likely problem was that its antenna did not deploy and that a stronger signal than they could generate was needed to send up new commands telling the satellite to wait until its batteries had recharged before trying again to deploy its antenna. They asked the amateur radio EME (Earth-Moon-Earth) community for help, and Rob Quick, VK1KW, came to the rescue. He was able to work with the satellite's ground controllers to transmit the new instructions, after which it appeared that the antenna was successfully deployed and the satellite came to life!

Finally on the satellite front, a constellation of five amateur radio cubesats built in five different countries was successfully launched to the International Space Station in early June. Once deployed later this year, the BIRDS-1 satellites will be part of an experiment in conducting VHF/UHF communications with amateur ground stations around the world. The challenge, according to the AMSAT News Service, will be to distinguish each satellite from the others – they're all on the same frequency – and to hand over satellite operation from one ground station to another. For more information, visit <>.