There's one guaranteed on every starting planet. They're filled with aliens not native to the planet's surface and often filled with plenty of useful items stored away. Abandoned Mine: A possible randomly generated area on planets.
It seems sometimes the Apex Miniknog take their experiments too far. The game receives semi-regular content updates and bugfixes, with the 1.4 Bounty Hunter update as the final update as of June 2019. Beta was released on December 4th, 2013 for all who preordered the game, and the final game was released on July 22nd, 2016.