Why is a nautical mile longer than a mile?
- Introduction
- What is a Nautical Mile?
- Why is a Nautical Mile Longer than a Mile?
- The Difference in Length
- How is a Nautical Mile Measured?
- History of the Nautical Mile
- Advantages of Using Nautical Miles
- Challenges of Using Nautical Miles
- Nautical Miles in the Modern Age
- Conclusion
- Sources
Introduction
Sailing has been with us since ancient times and so have nautical miles, which are units of measurement used to measure distances travelled through the water. A nautical mile is slightly longer than a mile on land and many people are curious as to why this is the case and how it is measured. In this article, we’ll explore what a nautical mile is, why it’s longer than a mile on land, how it’s measured, its history, advantages and challenges associated with it, and its place in the modern age.
What is a Nautical Mile?
A nautical mile (NM) is an international unit of length that equals 1,852 meters or 6076 feet or 1 minute of arc along any meridian (longitude line). It is based on the circumference of the Earth and one NM equals one minute of latitude at any given location on the globe. The term “nautical mile” was originally used to describe distances at sea but now it has become an internationally accepted unit for measuring distances across all bodies of water worldwide such as oceans, seas and lakes.
Why is a Nautical Mile Longer than a Mile?
The difference between a nautical mile and a mile on land arises as the earth isn’t perfectly spherical and instead has been slightly flattened at the poles due to its rotation around its axis. This means that if you were to measure out 1 degree of longitude around the earth’s surface (which would equal 60 minutes) you would find that it would be slightly longer at the poles than along the equator due to its flattened shape – thus making it slightly longer than 1 statute mile (a land mile).
The Difference in Length
The difference between a nautical mile and a statute (land) mile can be quite small depending on your location on earth – but typically equates to about 1/8th of an inch per nautical mile travelled when compared with land miles travelled over the same distance (this difference can be more significant closer towards either pole). It should also be noted that because most GPS systems use statute miles for their measurements, this slight discrepancy can lead to some confusion when sailors are trying to measure their distance travelled using GPS systems while out at sea!
How is a Nautical Mile Measured?
Nautical miles are typically measured using specialised equipment such as sextants or chronometers which use angular measurements based off of known points on earth’s surface in order to calculate distances travelled over water accurately – however modern GPS systems can also provide accurate measurements for nautical miles as well!
History of the Nautical Mile
Nautical miles have been used for centuries by sailors all over the world as their standard unit for measuring long-distance voyages by sea – however their exact origin remains unknown! It was first proposed by British navigator John Harrison in 1735 who suggested using longitudes (lines connecting two points) as an accurate method for measuring distances across bodies of water – however it wasn’t until 1854 that nautical miles were officially adopted as an international unit by countries around the world during The International Maritime Conference held in Washington DC that year!
Advantages of Using Nautical Miles
One major advantage associated with using nautical miles as opposed to other units such as statute miles when sailing lies in their accuracy when measuring long-distance voyages across bodies of water – due to their reliance on angular measurements taken from known points on earths surface which can be accurately calculated regardless of location or weather conditions! Additionally they are also easier to remember when trying to find locations while sailing, as they are divided up into minutes rather than feet or yards making them easy to quickly refer back too without needing complex calculations!
Challenges of Using Nautical Miles
Using nautical miles does come with some challenges however – primarily due to their slight discrepancy from statute (land) miles which can lead to confusion amongst sailors trying to use GPS systems for navigation purposes! Additionally because most maps still use statute miles for their measurements this discrepancy can also lead to some confusion when attempting to navigate without GPS systems or other specialist equipment such as sextants!
#NauticallMilesintheModernAge
The advent of modern technology has made navigation much simpler and more efficient today than ever before thanks largely due to advances in satellite mapping technology which allow sailors access accurate measurements regardless of location or weather conditions! Additionally most modern GPS systems now come pre-programmed with both statute and nauticallmile settings meaning sailors no longer need specialist knowledge or equipment in order calculate distances accurately whilst out at sea!
# Conclusion
Nauticallmiles have been used by sailors since ancient times but remain just as relevant today thanks largely due to advances made in mapping technology which allow sailors access accurate measurements regardless of location or weather conditions! They offer several advantages such as ease-of-use when trying remember locations whilst sailing but do come with some challenges primarily due discrepancy between them and statute (land) miles which can cause confusion when navigating without specialist equipment such sextants!
# Sources
1.”What Is A Nauticallmile?” National Ocean Service, NOAA Office Of Coast Survey https://oceanservice.noaa.gov/facts/nauticallmile2 . Accessed July 22nd 2022
