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Name: Seth
Status: other
Grade: other
Location: CA
Country: N/A
Date: 12/13/2005

What are the chances or is it possible to see a 'particle trace' in ordinary fog similar to what happens in a cloud chamber? Are there other places or circumstances where one of these particle traces might be observed?

A cloud chamber operates on the principle that a high energy particle/photon passing through a chamber that is SUPERSATURATED with some vapor provides a trail of sites for the condensation of the unstable vapor. The key is that the vapor phase is supersaturated and hence unstable. There are various ways of re-establishing the unstable state over and over again. When the particle/photon passes through the supersaturated vapor and the "seeds" for condensation of the unstable vapor are formed this track of fog particles is photographed. It would be highly unlikely that a supersaturated water phase could be maintained long enough to be able to observe a cosmic ray or some other particle traveling through the atmosphere. Supersaturation does occur in the atmosphere. This is observed occasionally when one experiences the beginning of a rain shower, or and increase in the rainfall, after a lightning stroke. But it would be difficult to "capture".

There are cases where high energy particles (alpha particles/cosmic rays), or radiation (x-rays), pass through condensed media and leaves a "damage" trail which is frozen in the solid phase and can be observed.

Vince Calder

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