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Q & A: fog and cosmic rays

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Most recent answer: 09/29/2013
Q:
Why don't we see cosmic rays outside whenever it is foggy? (like in a cloud chamber) Is this just because water has roughly twice the specific heat of alcohol? Or is it because normal fog isn't supersaturated?
- Dylan (age 20)
Ithaca, NY, US
A:

Water vapor is transparent. So when you see a lot of fog, that means that many tiny droplets have already condensed. Presumably those dense droplets keep the neighboring air from being supersaturated, since vapor can condense on the droplets. So the total amount of water, including the droplets, in the foggy atmosphere is above the saturation level, but the amount of water vapor isn't.

Mike W.


(published on 09/29/2013)

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