![1other asteroid_ill backpack bag commission crane_(machine) crater evening from_behind grass highres lens_flare mountainous_horizon o'neill_cylinder outdoors resolem scenery snow solo standing wide_shot wreckage rating:s score:2 post #3657944](/cdn_image/preview/b7/c4/b7c4a35aa814c7ae93017cf41f1b5d82.jpg)
A space colony design by Gerard K. O'Neill.
He called that particular design "Island Three" in his 1976 book The High Frontier: Human Colonies in Space.
This cylinder-type design is known for appearing (and being dropped) in most of the Gundam series (with a few exceptions).