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Re: Nautical Miles to Lat/Lon Degrees [message #17036 is a reply to message #17032]

Thu, 09 September 1999 00:00

jph
Messages: 2
Registered: September 1999

Junior Member

One nautical mile was defined to be one minute of arc
on the earth's surface. So moving north or south, the
displacement in degrees of latitude is (naut miles)/60.
Since the lines of longitude converge at the poles, the
the displacement east or west in degrees of longitude is
given by (naut miles)/(60*cos(latitude)).
But how accurate must this be? The foregoing assumes
a spherical earth, which is not quite true ...

Cheers,
Patrick Harrington

In article <37D7E259.83B9EFB6@ssec.wisc.edu>, Liam Gumley <Liam.Gumley@ssec.wisc.edu> writes:
|> David Fanning wrote:
|> > Does anyone know off-hand the formula for converting nautical
|> > miles to degrees of latitude and longitude for a given
|> > latitude and longitude? Pointers to appropriate reference
|> > materials is also appreciated.
|>
|> David, the following may prove helpful:
|>
|> According to my freshman physics text (Halliday and Resnick), 1 nautical
|> mile = 1.852 kilometers.
|>
|> For computing the distance in kilometers between a pair of lat/lons,
|> nothing beats the COMPASS routine from the ESRG library, available at
|>
|> http://www.astro.washington.edu/deutsch-bin/idllibsrch?keywo rd=compass
|>
|> Cheers,
|> Liam.
|>
|> --
|> Liam E. Gumley
|> Space Science and Engineering Center, UW-Madison
|> http://cimss.ssec.wisc.edu/~gumley

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[Message index]

		Re: Nautical Miles to Lat/Lon Degrees By: thompson on Thu, 09 September 1999 00:00
		Re: Nautical Miles to Lat/Lon Degrees By: jph on Thu, 09 September 1999 00:00
		Re: Nautical Miles to Lat/Lon Degrees By: davidf on Thu, 09 September 1999 00:00
		Re: Nautical Miles to Lat/Lon Degrees By: Liam Gumley on Thu, 09 September 1999 00:00
		Re: Nautical Miles to Lat/Lon Degrees By: Struan Gray on Thu, 09 September 1999 00:00
		Re: Nautical Miles to Lat/Lon Degrees By: davidf on Thu, 09 September 1999 00:00

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