re: (meteorobs) Hale-Bopp computation request

To: <meteorobs@latrade.COM>
Subject: re: (meteorobs) Hale-Bopp computation request
From: wayne.t.hally@bangate1.TEK.COM
Date: Tue, 18 Feb 97 3:44:30 EST
Reply-To: meteorobs@latrade.com
Sender: owner-meteorobs

Gregg wrote:
Over some reasonable interval, for example present to May 15, and at
some reasonable frequency, one to five days, for latitude 45 degrees
(I live at 47, but I'm willing to compromise), please compute in
tabular form the times for the following events, Sun Rise/Set,
Astronomical Twilight End/Start, Moon Rise/Set, and Hale-Bopp
Rise/Set.  What I'm trying to create is a chart that shows observation
opportunities for Hale-Bopp, similar to the S&T all-year chart.

Wayne comments:
	I would recommend using nautical twilight as a better representation 
of when twilight becomes an impediment to observing. I've carefully 
measured LM throughout the twilight periods for meteorobs, and have found 
that if skies are clear, obvservations are only minimally affected between 
astro and nautical twilight. After that,(in the morning) conditions 
deteriorate very rapidly, so that by civil twilight, the sky is quite 
bright (LM~ 2).
	Just my 2 cents worth, 
Wayne