A sealed hab dome, containing a fish breeding tank that outputs a portion every so often into another tank, and a flock of penguins. There are also penguin shaped space suits mounted next to the air locks
Ooh. A small broken octagonal habitat shape with the fossilized remains of dolphin bones and dolphin shaped mechanized suits. As well as some kind of buried damaged “launch pad” that could fit a decent sized ship.
Wait… that would be less confusing and more exciting as a earths history kind of thing.