I was playing Kerbal Space Program, and I just touchdown on Kerbin after a manned mission to Mun. As a kerbal was climbing out of the lander can, the screen went dark and his altimeter went absolutely chaotic. When it finished turning, it landed on 666666m. I hit escape and returned to the space center. I clicked on the tracking station and found that the entire solar system was missing. I couldn't see any planets, missions, orbital trajectories or anything. It did however show what missions I still had present on the left of my screen. I decided to click on a familiar satellite I named "Derp." And it homed in on a piece of debris of the satellite, a stage that decoupled and was still orbiting Kerbin. However, I could not find the Kerbin. I restarted, and the solar system had returned. However, the mission that contained the two pilots and the lander were gone. The only thing that remains is the staging for the lander which remains on the surface of Mun. Here is a screenshot I took of Jonsey Kerman, when the altimeter settled. Someone call an exorcist.