Why nautical miles in marine navigation?

Question

Why did a unit of measurement, the nautical mile, become widely used in marine navigation? Why use a measurement which is a different length than a standard statute mile?

And conversely, if the nm was found to be so useful, why wasn't it applied to land measurements? Why not just bump up the old mile distance to be in tune with a nm?

Answer 1

+ There is correct info in the other answers, but they do not mention the fact that a NM is considered 2,000 yards. It is very easy to do all of the calculations and formula's with 2,000 yards as a standard. With a little practice on the formulas you can do most of your math in your head.

Example: Distance = Rate(speed) x Time

How far have I traveled at 5 knots for 1 hour
Knots are nautical miles per hour
10,000 yards
EASY?

Answer 2

The Romans gave us the idea of the land mile - measuring off paces of the soldiers that marched to all places in the empire. But they couldn't measure the seas the same way. The measurement of the seas, and subsequently the airways, had to be measured differently, and the use of the angles and arcs of the earth (described in the other answers) made much sense in dividing the earth, and being able to measure across great distances. Finally, the nautical mile was accepted and officially put in place by the "powers that were" at the time (mostly British I think), and so were internationally accepted. The land mile has actually got it's own great number of "official" variations, depending on what country you are in! So, like the measurements of the months (by Gregorian decision or by 28 day moon cycles), the measurements of the earth came from different backgrounds, got accepted in their various fields, and became pretty solidly accepted and used, making them hard to switch back and forth (though you can convert, if you wish).

I searched to find a good site that would further explain this, and here is one the simplest I could find:

Good luck! :)

Answer 3

In the Latitude/Longitude system, you have degrees, minutes, and seconds. In latitude, they are all equal. In Longitude, they vary depending how far you are from the poles. One minute is one nautical mile or 6076 feet. You could use a sextant to find your latitude and longitude and know where you were. People never navigated that way on land. You could throw a piece of wood overboard with a rope attached and knots in the rope. However knots went by in a specified time period told you your speed. If you were doing 2 knots, then you would go 2 nautical miles, or 2 minutes on the chart in distance of latitude.

Answer 4

The nautical mile's utility relies on its approximation to an even 1 arc-minute of latitude. The nautical mile is used in day-to-day long distance navigation estimates in restricted water piloting of vessels large or small.

Answer 5

A nautical mile is comparable to some million.one million miles. it somewhat is the area of one minute on the map. Charts and GPS all have minutes logged, so it exchange into in basic terms an person-friendly uniform unit of degree. the sole industries that use nautical miles that i'm attentive to incorporate boating and air appropriate. in case you realize others, i'd be interested in looking out.

Answer 6

Because it is 1 arc minute of degrees around the earth at sea level.
I knot is 1 nautical mile per hour. So it is easy to navigate on maps.

Answer 7

A nautical mile is equal to a minute of arc along a meridian of the earth and so makes it easier to estimate changes of latitude on a nautical chart.

Answer 8

Because you can't walk on water unless your JC.