by Nitpicker » Sat Dec 06, 2014 9:51 pm
Guest wrote:Just a quick FYI...
A nautical mile is a unit of measurement used by navigators in shipping and aviation. It is the average length of one minute of one degree along a great circle of the Earth at the surface. One nautical mile corresponds to one minute of latitude. Thus, degrees of latitude are approximately 60 nautical miles apart. By contrast, the distance of nautical miles between degrees of longitude is not constant because lines of longitude become closer together as they converge at the poles. In addition to being used in navigation and aviation, nautical miles are also used polar exploration and international laws and treaties regarding territorial water limits. Also, for reference, there is no metric conversion the for 360 degrees of a circle/sphere. And before someone mentions it, PI would still remain 3.14159265...... because it is a ratio and independent of the unit of measure (the units cancel)
The original reason the metre (or meter) was made the length it is, was so that the shortest distance along the Earth's surface, from equator to pole, could be expressed as 10,000,000 m, or 10,000 km. These days, the definition of the metre has been refined, and the nautical mile has been redefined in terms of the metre, so that neither are defined precisely by the Earth, but the circumference of the Earth is still pretty close to 40,000 km, or 21,600 nautical miles, no matter how you measure it.
[quote="Guest"]Just a quick FYI...
A nautical mile is a unit of measurement used by navigators in shipping and aviation. It is the average length of one minute of one degree along a great circle of the Earth at the surface. One nautical mile corresponds to one minute of latitude. Thus, degrees of latitude are approximately 60 nautical miles apart. By contrast, the distance of nautical miles between degrees of longitude is not constant because lines of longitude become closer together as they converge at the poles. In addition to being used in navigation and aviation, nautical miles are also used polar exploration and international laws and treaties regarding territorial water limits. Also, for reference, there is no metric conversion the for 360 degrees of a circle/sphere. And before someone mentions it, PI would still remain 3.14159265...... because it is a ratio and independent of the unit of measure (the units cancel)[/quote]
The original reason the metre (or meter) was made the length it is, was so that the shortest distance along the Earth's surface, from equator to pole, could be expressed as 10,000,000 m, or 10,000 km. These days, the definition of the metre has been refined, and the nautical mile has been redefined in terms of the metre, so that neither are defined precisely by the Earth, but the circumference of the Earth is still pretty close to 40,000 km, or 21,600 nautical miles, no matter how you measure it.