"Oliver Wen" wrote:

Does that mean that there is too much uranium in the ground ?

This is natural. It always interests Boy Scouts when they see fungi
glowing in the woods. It is quite prevalent, at least here in
Pennsylvania. In a fungi, it is to attract insects to spread the
spores. Chemically it is the enzyme luciferase acting upon the compound
luciferin to break it down and release the energy as one photon of light.

There is information on this at:

http://www.digitaltermpapers.com/view.php/d/262.HTM

and

http://maguires.com/research/luminous_mushrooms.htm

There are also bioluminescent bacteria (Photobacterium), plants
(dinoflagellates) and insects (fireflies).

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Cheers, Steve Henning in Reading, PA USA
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