The farthest spacecraft from home is back to making long-distance phone calls.
Communications have been restored with Voyager 1. (Image credit: NASA)
NASA has confirmed that one of its greatest ever missions, Voyager 1, is back in business with communications restored following an incident in October that had led to the veteran spacefarer losing its voice.
Now 47 years old, Voyager 1 is 15.4 billion miles (24.9 billion kilometers) from Earth, a distance that grows greater with every passing second. With the power supply from its decaying plutonium dwindling, only four of its instruments remain operational — and surprisingly so, given they are now all working at temperatures lower than they were originally designed for.
So, when engineers commanded Voyager 1 to switch on one of its heaters to give the instruments a gentle thermal massage, a safety feature was tripped because of low power levels. The spacecraft’s fault protection system monitors how much energy Voyager 1 has left, and if it deems there to be too little energy for the probe to continue operating, it automatically switches off non-essential systems. It seems that the heater was using too much energy, but the problem was that all the non-essential systems had been switched off long ago to conserve what little power remained, so the fault protection system took it upon itself to switch off the main X-band transmitter and activate the lower-power S-band transmitter instead. Because of the great distance between Voyager 1 and Earth, however, transmissions on the S-band antenna could not be heard by NASA’s Deep Space Network, meaning that Voyager 1 had effectively fallen silent.