BBC Focus Magazine

[Shadowwolf]

We drink water, bathe in it and we are made mostly of water, yet the common substance poses major mysteries. Now, University of Utah chemists may have solved one enigma by showing how cold water can get before it absolutely must freeze: 55 degrees below zero Fahrenheit.

That's 87 degrees Fahrenheit colder than what most people consider the freezing point of water, namely, 32 F.

Supercooled liquid water must become ice at minus 55 F not just because of the extreme cold, but because the molecular structure of water changes physically to form tetrahedron shapes, with each water molecule loosely bonded to four others, according to the new study by chemists Valeria Molinero and Emily Moore.

http://www.sciencedaily.com/releases/2011/11/111123133123.htm

[Healerman]