Fluids and gases can move in strange and mysterious ways that aren’t always apparent to our unaided eyes. It's only with the use of tracers or dyes, photographic techniques and a bit of luck, that we can capture fluid dynamics in action.

Here are some of the weird and beautiful ways in which fluids flow.

Above:

When an object moves faster than the speed of sound, funny things start to happen. The bullet in the image above is moving so fast, the air in front of it can’t get out of the way quickly enough. So it starts to pile up in front of the bullet, forming an area of compressed air — a shock wave.

The same thing happens with supersonic jets. As they fly faster than the speed of sound, they build up a shock wave in front of them. The sonic boom that accompanies these aircraft is actually the wave of compressed air hurtling by your ears.

Image: Andrew Davidhazy/Rochester Institute of Technology