Think of it as conditions in the subsurface of a planet where you are very far away from a sun, but you still have water, energy, nutrients, which for some of them means food, and a protection.
把它想成 某个行星次地表的环境， 在那里你离恒星很远， 但你仍旧有水、能量、营养， 对于其中一些生物来说， 这意味着食物和保护。