From the publisher's website:
Distant Worlds is a vast, pausable real-time, 4X space strategy game. Experience the full depth and detail of large turn-based strategy games, but with the simplicity and ease of real-time, and on the scale of a massively-multiplayer online game.
Vast galaxies are made to order: up to 1400 star systems, with up to 50,000 planets, moons and asteroids. Galaxies are so deep, fun and immersive that you won’t want to finish the game... Build, expand and improve your empire endlessly. The galaxy is packed with life and activity. Encounter other empires, independent alien colonies, traders, pirates and space monsters. Explore star systems, asteroid fields, gas clouds, supernovae, galactic storms and black holes. Discover evidence of civilizations long since past, uncovering secrets about the galaxy's troubled history...
Best of all, you can play the game your way: enjoy a quick, intense game in a crowded galaxy or take your time in an epic game spread across a vast galaxy!