The command module was the home of all three astronauts during most of the mission, and the only part to return intact to Earth. (In the film Apollo 13, it was damaged by an explosion, so the astronauts had to move to the lunar landing module.) It sits atop the service module, which is accessible by a dock shown in the 3D model. The astronauts can then traverse the service module and access the lunar module via a docking tunnel.

"The command module had many, many hidden nooks and crannies that are really hard to see," says Vincent Rossi, the senior 3D program officer. It's also composed of reflective surfaces that make scanning tough. The museum enlisted Autodesk, which created custom 3D scanning equipment and developed algorithms to pull all the data together. After removing the protective plexiglass from the module, the Smithsonian 3D team used seven scanning techniques to capture the interior of the module in sub-millimeter detail.

During the process, the museum's curators saw parts of the interior they weren't able to get to before, since the fragile capsule has barely been touched since 1971. That includes hand-written astronaut "graffiti" including a calendar, instructions from mission control and a note on a panel that reads "launch day urine bags." According to the museum's blog post, "seeing such details and studying the text have enhanced curators' understanding of how the missions were conducted," and possibly the astronauts' senses of humor, too.