Not too surprising...I meant to mention that the inverse cos is
intended to provided an angle in *radians*
1 radian = 1 degree X 180/pi or about 57 degrees.

Brian W

On Fri, 05 Dec 2003 02:51:48 GMT, (Larry W4CSC) wrote:

Fifty seven lurkers just headed for the Tylenols with their heads
spinning, feeling nauseated and dizzy....(c;

I love my Nautical Almanac.....
I love my Nautical Almanac.....
I love my Nautical Almanac.....
I love my Nautical Almanac.....
and GPS...



On Fri, 05 Dec 2003 00:27:38 GMT, Brian Whatcott
wrote:


First, an explanatory note:
inverse cos is also known as arc.cos or cos^-1

The great circle distance is given by
Earth radius * arccos [cos Lat1* cos Lat2 * cos (Long1 - Long2)
+ sin Lat1 * sin Lat2]
The Earth (equatorial) radius is
6378 km, or 3963 statute miles or 3442 NM.

Does this help? (There are other formulae for the same result...)

Brian Whatcott Altus OK


Larry W4CSC

NNNN