Whoa, Watch Bacteria Instantly Turn Water Into Ice

How does it work? It's the same principle behind how snow forms in the atmosphere (and in artificial snow machines, too-we'll get to that later). An ice crystal needs to form around a nucleus, which can be a bit of dust, soot, pollen, or, as we've seen, bacteria. Pure water doesn't have to crystallize into ice until it's as cold as 55 F below zero. In the demo here, the water has been supercooled to about 21 F, but it only freezes over after the P. syringae is added.

Maggie Koerth-Baker, who first spotted the video for Boing Boing, explains where P. syringae's cold superpower comes from.

In its earthbound life, P. syringae causes disease in plants, so its snow-forming ability might seem bizarre. One hypothesis is that ice nucleation is really a subtle means of hacking the weather system: bacteria drifts up into the atmosphere and falls back to earth as snow and hail, traveling hundreds of miles in between.

We humans might think ourselves clever using bacteria proteins to make artificial snow for ski resorts, but the microbes have been way ahead of us. [Mark Martin via Boing Boing]