VOYAGER 2 SWITCHES TO BACKUP THRUSTERS

NASA has had many successful missions in space, but the Voyager program has to come near the top of the pile. Two identical unmanned probes called Voyager 1 and Voyager 2 were launched in 1977 to study Jupiter and Saturn. But both have continued their flights through space, still functioning after 34 years and regularly communicate back information to Earth.

In those years both probes have been traveling away from Earth. Voyager 2 is now over 9 billion miles away in the heliosheath and will eventually leave our solar system completely. But to do that, and continue operating, NASA has to carry out a switch to a backup set of thrusters that have not been used in flight before.

The switch is necessary in order to save power in the region of 12 watts. In saving that power, Voyager 2 will go from requiring 270 watts to 258 watts. It may not seem like much, but as the power reserves on the probe diminish every little helps, and that saving could mean an extra decade of operation.

The 12 watts of power is currently being used up by a heater keeping the fuel line to primary thrusters warm. Switching to the backup thrusters used for roll motion means that fuel line is no longer required. The one concern being that these thrusters have never been used before in flight, so will they function after all this time?

Reassurance comes from the fact that Voyager 1 made the same switch in 2004 without issue, and had fired its main thrusters more times (353,000) than Voyager 2 (318,000).

NASA issued the command to switch on November 4th, but won’t know if it has been successful until November 14 when it receives communication from the probe as to what happened. Hopefully it will go without a hitch and we’ll still be hearing from Voyager 2 in 2021. [Geek]