NASA is kind of awesome. In case you live under some red rocks, the organization sent this crazy robot to Mars that sends us back high-resolution photos. The future is amazing. Of course, there's nothing the space administration loves more than curiosity (which is why they named the Mars rover after it), and it's aiming to fuel yours with this 3D model explorer.
In a somewhat odd move, instead of simply providing the 3D models themselves, the app requires you to print out some markers. Then, as you've seen in other AR apps, you point your camera at the page and the model appears. You can move your handset around it, move in and out, and explore every part of the virtual object.
The app is free and more models will be added over time. If you want to explore the things that are exploring space, grab it from the widget below.