Internal and external views of the AtLAST concept CAD model. Left: rendering of the complete telescope, using the AtLAST CAD model. A truck is shown for scale. Right: exploded view of AtLAST that highlights the internal components. The exploded view shows, from top to bottom, M2, M1, the backup structure, the elevation rotating structure, (offset to the right) the azimuth rotating structure, and the underground cabling structure that is part of the azimuth cable wrap. The Nasmyth platform is highlighted in yellow here, and the Cassegrain platform is highlighted in green.