I own it and have played it. It's a lot of fun and is soloable.
Why is it fun? It's an interesting premise (space) and there's a lot of paths to obtaining victory. You gain resources and abilities through card play, which admittedly can get to be a little much in the late game (you might have seen pictures of this game with tons upon tons of cards played by each player). When you obtain a card of some kind, you can play it to your play area, and it'll give you some kind of function or bonus; some cards trump others and still others can cause a cascading effect. (It's at heart an engine-building game, so that's a given.) There's a LOT of cards so you'll need a decent play area to deploy them, especially if you're going with multiple players.
There's a lot of expansions for it too, which I do not own. I've been told that the Prelude expansion, though, is imperative if you like the base game. Prelude is, as the name suggests, a 'prequel' to your game to allow for a faster start.