Aurora

Aurora is a roguelike space exploration game, in part inspired by Star Control 2. There are loads of features already implemented, incluing randomly generated galaxies, various star systems with planets and ships, simple space combat, planetary exploration, research, a dialogue system, quests, a global story, a diplomacy system and more. It looks really well-made and I appreciate the huge variation in gameplay elements that it's built around.

Planet exploration with combat in Aurora.