Two part question

1) What is an Aphotic planet?

2) Since they are in another galaxy and you use a special scanner that finds uninhabited ones, can anyone else scan the ones I have already colonized?

Aphotic planets (aka 'Shadow planets') are worlds that receive little to no sunlight from their host star, but their cores produce enough heat to prevent the surface from freezing. They exist inside the Vorigar Expanse, a large region of the existing galaxy. Due to the amount of the Silthion gas in the Expanse, all planets within it are Aphotic.

For more backstory on the Silthion, some info has been added to the Races page:
http://galaxylegion.com/wiki/index.php? ... thion_Hive

Once discovered for the first time though the mission, Aphotic planets can be discovered by other players through normal scanning. To match the story, we may decide to add passive cloak to all Aphotic planets in the future.