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View Full Version : Circle aroudn moon 12:30am january 28



2002-Jan-28, 04:25 AM
Just looked outside saw a big circle around moon, a friend at notre dame saw it as well. What did we see. Tried to take a picture on digital camera but it didnt show up and we cant ajust timing.

DStahl
2002-Jan-28, 04:56 AM
Probably a layer of ice crystals high in the atmosphere reflecting and/or refracting the moonlight. Even when the sky looks quite clear there can be high hazes like this--where I live it often means moisture moving in and a storm on the way. There can be beautiful effects, especially in winter when small flat-faced ice crystals reflect sun- or moonlight. I once saw a brilliant pair of sundogs with partial arcs and a sun halo just before a snowstorm in the Cascade Mountains.

Enjoy it! Not enough people remember to look up.

--Don Stahl

Kaptain K
2002-Jan-28, 08:53 AM
What you saw is known as a "halo". They are very common, both night (moon) and day (sun). They are a subset of a phenomenon known as "parhelia". In our modern technological world, many of us have lost connection with the world around us. As DStahl said, halos are often a portent of storms moving in. If you make a habit of looking for them whenever there is a high haze or cirrus clouds in the sky, you can probably see the once a week or more.
For more information, try here:
http://www.sundog.clara.co.uk/halo/halosim.htm
or try a Google search for "parhelia".