You build rockets and try to explore space. Overall, the game does deliver that very good. The career mode gives your progress some structure which makes it easyer to get into the game. As far as I can tell it, the physics are generally quite well for a game too. There is a Demo out there which I tried first and I think it doesn't do the complete game justice. I found the game much better than what the Demo showed at first. The biggest negative point, which leads to only 3 stars in my review, is that it crashes far too often. It crashes about once every 2 hours for me (win 10, a4-6300, integrated graphics).