--- On Wed, 10/20/10, Michael Vanopstall <opstall@math.utah.edu> wrote:
From: Michael Vanopstall <opstall@math.utah.edu>
So I'm curious about other peoples' experience: how far away from an object does the moon have to be to affect its visibility? If the moon is out, and near full, but on the other side of the sky, does it have little effect? If it is still technically not set, but obscured from view by a mountain, is that even better? Even when set, you can still see the light from the moon. Is this basically benign, if you're looking the other way?
Rev. Michael A. van Opstall Department of Mathematics, University of Utah
With long drive times and equipment setup I prefer to have at least a 4 hours of no moon between the astro twilight times for dark sky viewing.
From a very dark site I can detect the lunar twilight up to 2 hours from the rise or set of the half moon. Even a 20% crescent will make a glow that mimics the zodiacal light. So I pick a location where the moon will rise or set over the distant city glow where it will leave me the most dark horizions.
For social events for the public I will go out and look at the moon itself but I prefere a second option like Jupiter or Saturn to make the night more complete. Last Saturday I set up at SPOC with a bright moon and bright cloud cover but was still able to show people the Hercules cluster, the Ring nebula, the Double Cluster, and the Andromeda Galaxy, as well as Moon, Jupiter, Urans, and Neptune. DT