Ah. I'd spotted the Magellanic Clouds. Was confused about Andromeda because it doesn't look like I expected - I suppose because it's depicted in-game with optical light only, whereas most pics I've seen are false-colour infrared and x-ray mixed in with optical. Thank you very much, mystery solved.Andromeda Galaxy.
The other one (just out of shot to the south west) that looks more like a whirlpool is the Triangulum Galaxy, and the two clouds next to each other are the Magellanic Clouds.