Launched in 1977, both Voyagers now report from interstellar space using a transmitter weaker than a fridge bulb. Engineers switch off instruments one at a time to stretch the remaining power.

A command sent from Earth takes most of a day to arrive, and the answer takes just as long to come back. The team plans every shutdown years ahead, choosing which science to keep alive the longest.

Why it is in the vault: it is the kind of find worth coming back to. Add sources, corrections and related links in the discussion thread.