Oops, backwards. For -12 degrees that would be a little Less civil and little More nautical. Now he prob will be less civil! :-) Jack > http://aa.usno.navy.mil/faq/docs/RST_defs.html > > Civil twilight is defined to begin in the morning, and to end > in the evening > when the center of the Sun is geometrically 6 degrees below > the horizon. > > Nautical twilight is defined to begin in the morning, and to > end in the > evening, when the center of the sun is geometrically 12 > degrees below the -- See message header for info on list archives or unsubscribing, and please send personal replies to the author, not the list.