You’re actually looking at the result of a scientific experiment performed by engineer Hoi Dick Ng from Concordia University in Montreal. It involved a tank of water, with a cylindrical gate lodged in the middle. Ng kept the water level inside the gate lower than in the surrounding tank; then, when the gate was suddenly removed, high-speed cameras captured the moment when water rushed into the empty space.
The original images were black and white, but this image has been colourised according to pixel darkness — the result, more or less, shows the shape and height of the water’s surface just after the gate was removed. It looks so good that the image actually won a prize from the American Institute of Physics, when it was named the best fluid dynamics image of 2012. Prize or not, it looks stunning — why not print it out and hang it on your tree? [American Institute of Physics via Scientific American]
Picture: American Institute of Physics