[Boatanchors] Radio Ranges/Nautical Mile/Navigation

[J. Forster]

Bill Pileggi wrote:

> I hope this isn't too far off on that "how much is a nautical mile thread", and may pose a neat question at the end.
>
> A nautical mile, by definition and agreement, is 1852 meters. 1852 meters is equal to 1 second (of arc). 60 seconds is equal to 1 degree (can you see where this is going?). 360 degrees equals a 'great circle' path around the earth, or a line of longitude. Do the math, starting with 1852 meters and you end up with the approximate circumference of the Earth.

Nope. A Nautical Mile is 1 MINUTE of arc at the equator, not 1 second. 1 arc second is about 100 feet on the earth's surface. See my earlier post.

How far is an hour? There are two answers:

The one you mean is:

The earth rotates at 15 degrees per hour (1/24  of 360 degrees); so . 15 deg. x 60 min/deg = 900 Nautical Miles

And:

The OTHER answer is 1 light hour = 186,000 mi/sec x 60 sec/min x 60 min/hr = you do the math.

-John