There is a certain beauty in the most terrible things. I came across this photo a while ago, and sent it to a friend, asking if he could guess what it was. Although he is a PhD in Physics and works in a highly technical field, his guesses were all, understandably, around organic objects - viruses, fungi and so on.
In fact, it is a nuclear explosion. During the American nuclear tests of the 1940s, they needed a fast-action camera to capture the explosions and the events of the milliseconds following, as part of the research. Harold Egerton developed the Rapatronic lens, which could capture an exposure of one ten-millionth of a second, and this photo (and the ones below) are the result. The exposure was made less than a millisecond after detonation, when the advancing front of the explosion has not yet reached the ground. The glowing spikes below the ball are an example of the 'rope trick effect', where the ropes holding the tower absorb the intense light of the explosion, heat up and vaporise. The following images show the same scene a couple of milliseconds later.
I find these images both eerily beautiful and terrifying.
Explanations here, here and here.