Has anyone tried one of those CO2-emitting mosquito traps? While they are designed to collapse populations of extended areas over time, I have read that they are quite effective at immediate relief over smaller areas. I have thought of getting one for my backyard this summer. The units that combine a UV source with CO2 emission are said to be the most effective. The heat plume from the propane burner would be similar to that produced by a candle- probably not enough to degrade seeing unless you were right next to it. One of the smaller units could be setup in the general vicinity of a group of observers. __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com