Check this out...the RTS portion of the game looks a little rough. But the trailer gets interesting at about 3:40. Turn based space component, as well...A little reminiscent of Star Wars: Empire at War.
https://www.youtube.com/watch?v=U1RxEi0ZSG4 (https://www.youtube.com/watch?v=U1RxEi0ZSG4)