Watcher

Watcher allows machinery like Copper Quarry or Extraction Lab to work even if the player is very far away. Without it Starbound would "unload" some parts of the map if you haven't been nearby in the last 15 seconds (and that would stop the machines).

To use it, craft a Watcher and place it within 20 blocks of the machines that you want to keep "awake". Then interact (E) with Watcher to turn it off.