You can use Excel to compute the "as the crow flies" distance between any two points on the earth.

The formula to compute this distance is:

=RadiusEarth*ACOS(COS(RADIANS(90-(Lat1*24)))*COS(RADIANS(90-(Lat2*24)))+
SIN(RADIANS(90-(Lat1*24)))*SIN(RADIANS(90-(Lat2*24)))*
COS(RADIANS(24*(Long1-Long2))))

Where
Lat1 is the latitude of point 1, entered as DD:MM:SS.
Long1 is the longitude of point 1, entered as DD:MM:SS.
Lat2 is the latitude of point 2, entered as DD:MM:SS.
Long2 is the longitude of point 2, entered as DD:MM:SS.
RadiusEarth is the radius of the earth (3,963 miles or 6,377 kilometers).

The function above works only for points in the Northern and Western hemisphere, where Latitudes and Longitudes are considered to be positive. If you are mixing hemispheres, enter Northern and Western coordinates as positive, and Southern and Eastern coordinates as negative, and use the following formula:

=RadiusEarth*ACOS(COS(RADIANS(90-Lat1))*COS(RADIANS(90-Lat2))+
SIN(RADIANS(90-Lat1))*SIN(RADIANS(90-Lat2))*COS(RADIANS(Long1-Long2)))

In this formula, Lat1, Long1, Lat2, and Long2 must be entered as decimal degrees (e.g., 45.5 rather than 45:30:00).

gonyen