Voyager 1 still alive

On October 16, NASA beamed a command to Voyager 1 to turn on one of its heaters. The spacecraft responded by ghosting Earth.

It actually took the agency two full days to notice the issue. That's because Voyager 1 is the most distant human-made object, and being almost 25 billion kilometers (15.3 billion miles) away, it takes nearly 23 hours for a message to get there – even at the speed of light – and another 23 hours for a response.

On October 18, Voyager 1 missed its scheduled return call. NASA's Deep Space Network (DSN) scanned for the signal and eventually found it on a slightly different frequency band.

It seems that the heater triggered Voyager 1's built-in fault protection system. If an instrument tries to draw too much power, this mechanism will automatically shut off other, non-essential systems to conserve energy.