This is an excellent example of super cooled liquids. If pure water is not disturbed and is truly pure, it can be chilled well beyond its normal freezing point (0 degrees C). If there is nothing for the water to crystallize around all is fine, it stays a liquid. The water can stay liquid down to -42 C, past that the water will crystallize on it’s own. If something is introduced like a mote of dust or tiny bubbles caused by moving the water, a chain reaction occurs and the body of water freezes. More super cooling examples are here: Supercooling Experiment 1 Supercooling Experiment 2 Supercooling Experiment 3 BTW, the guys on Digg are saying that it’s a hoax. I doubt it, I’ve had this happen to be before. Its happen with bottles of water or water in an ice tray in the freezer, and even a can of Coke. The Coke froze into a can of slush as soon as it was opened, I think the vending machine was set a little too cold that day. Conditions need to be just right for this to happen in your home freezer. The circulating fan will more than likely cause your supercooling experiments to fail. If you unplug the refrigerator just remember to plug it back in. Looks like fun, I have some water in the freezer in hopes I too can make instant ice. [inspired by digg] Wikipedia entry on supercooling
