User blog comment:Scooter8pie/As Far As the Eye Can See/@comment-4583259-20111129133724

As far as generating mobs is concerned, I think it has more to do with saving the game (which you noticed and commented in my moat article). If you work in an area for a long time you're probably not saving the game too often.

In my Geology excavation project I stopped seeing all types of Mobs for several hours, but then when I went back there to make the elaborate tunnels and platforms for making this photo: (File:GE-cocktail-party.jpg), I started getting more Astronauts.