During times of strong volcanic eruptions, when the atmosphere is saturated with volcanic dust, the fully eclipsed Moon is almost invisible, a phenomenon that I have experienced personally.

http://sunearth.gsfc.nasa.gov/eclips...E2004keen.html

Dave Mitsky

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Chance favors the prepared mind.
De gustibus non est disputandum.
Never attribute to malice that which can be adequately explained by stupidity.