The diorama started with a shell, 70- by 30-feet long with a half-domed ceiling. Though larger than most dioramas found throughout the Museum, the beginnings of this Mars-scape are otherwise very similar to the Museum’s existing three-dimensional exhibits. But there is one major difference: The Mars diorama is the first to depict a location never seen firsthand by human eyes.

The craggy Martian landscape begins to take shape with a rebar armature onto which fabricated rock will be sprayed. These rock formations will help to create a forced perspective, so that the viewer will actually feel as though the surface of Mars is just outside the diorama window.

Concrete infused with air, called shotcrete, is sprayed onto the framework, giving the rock structure its basic shape. Dr. Lee, a Mars expert, worked closely with the contractors that applied the fabricated rock, showing them photographs of the Martian surface; high-resolution topography of Candor Chasma; and information on Martian rock composition.

In addition to sharing images of Mars with the diorama’s fabricators, Dr. Lee also took them on a field trip to Roxborough State Park and Red Rocks. The rocks found at these two Colorado locations are hypothesized to be very similar to the rocks found on Mars. “Martian rocks are mainly sedimentary, similar to the layered, multicolored rocks found in Colorado,” Dr. Lee explains.

After the shotcrete is set, painting and sculpting the surface begins. Fabricators and scientists chose eight shades of paint to define the strata and shadowing on the rock. They used trowels, pointers, and scraping tools to carve details into the surface, then threw Martian-type gravel onto the wet concrete floor to simulate the dust-covered surface.

Next, work began on the huge diorama background. Artist Jan Vriesen, known for his work on dioramas in museums around the world, painted the Martian landscape. The time of day and year chosen for the diorama—90 minutes after sunrise in the early summer days of the Martian year—are carefully depicted in the color and brightness of the greenish yellow sky. Towering mesas, calculated by scientists to be 15,000 feet high, loom in the background. And in the foreground, two-dimensional rock formations blend with three-dimensional terrain.

Look out the window, what do you see? Upon first viewing Chandor Chasma through the Mars diorama glass, visitors to Space Odyssey may initially feel as though they have been transported to another planet. That suspension of disbelief, created by forced perspective, Martian color scheme, and careful attention to detail, is exactly what artists, craftsmen, and scientists are hoping you will feel.