Where's the coldest spot in the universe? By Tom Shachtman
http://www.smithsonianmag.com/science-nature/12359501.html
Smithsonian magazine, January 2008
This week it felt like Chicago was the COLDEST SPOT in the universe ! But Physicists in Massachusetts come to grips with the lowest possible temperature: absolute zero
Where's the coldest spot in the universe? Not on the moon, where the temperature plunges to a mere minus 378 Fahrenheit. Not even in deepest outer space, which has an estimated background temperature of about minus 455°F. As far as scientists can tell, the lowest temperatures ever attained were recently observed right here on earth.
The record-breaking lows were among the latest feats of ultracold physics, the laboratory study of matter at temperatures so mind-bogglingly frigid that atoms and even light itself behave in highly unusual ways. Electrical resistance in some elements disappears below about minus 440°F, a phenomenon called superconductivity. At even lower temperatures, some liquefied gases become "superfluids" capable of oozing through walls solid enough to hold any other sort of liquid; they even seem to defy gravity as they creep up, over and out of their containers.
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A good read !
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