Uh... I don’t think many people would consider Skyrim to be “in space.” I mean, sure it has celestial bodies that make it easy to tell that Nurn is not Earth, but that’s just because it’s a fantasy world.
Otherwise, there’s quite a few similarities. Both are action RPGs with a plethora of characters to interact with. Both have an “ancient evil has awoken” style plot line. I’m not going try and find every example.
Anyway, my original point wasn’t even to say Skyrim and Mass Effect are alike. My point was that they have both captured my imagination in different ways, and that I’ve been waiting for a game that combines the strength of both.