From Halopedia, the Halo wiki
The artists did not create an original design for this station. Instead they used a model created in Google Sketchup and uploaded to the 3d Warehouse. See here: http://sketchup.google.com/3dwarehouse/details?mid=6b63a5aaac9830f44aa009184b3a1b04.
This model was uploaded about 2 years before Invasion was released. 18.104.22.168 19:10, 22 April 2013 (EDT)