For example, the surface of a giant doughnut is another 2D space. When you look around the universe you live in, it looks like a 3D space, just like the surface of the Earth looks like a 2D space.

With Smithsonian Open Access, we’re increasing the public’s ability to use millions of digital assets—2D and 3D images and data. Open Access items carry what’s called a CC0 designation. This means the ...