What is a US Nautical Mile?
A US nautical mile is a unit of measurement used primarily in navigation and marine activities. It is defined as exactly 1,852 meters or approximately 6,076.12 feet. The term "nautical mile" originated from the need for sailors to measure distances on the Earth's surface while taking into account the curvature of the Earth.
The US nautical mile is based on the international nautical mile, which was established in 1929 by the International Hydrographic Organization (IHO). The IHO defined the nautical mile as one minute of latitude along any meridian. Since the Earth is not a perfect sphere, the length of a nautical mile varies slightly depending on the latitude. However, for practical purposes, the US nautical mile is considered a fixed value.
The US nautical mile is commonly used in marine charts, navigation systems, and aviation. It provides a convenient and standardized way to measure distances at sea, ensuring accurate calculations for ship and aircraft navigation. Additionally, it is used in the calculation of speed over water, known as knots, where one knot is equal to one nautical mile per hour.
What is a millimeter?
A millimeter is a thousandth of a meter (1/1000) which is the SI (International System of Units) unit of length. It is normally used to measure small lengths like the thickness of a sheet of paper or the dimensions of a small object.
One millimeter is approximately equal to 0.03937 inches (about 1/25th). Presicely there are 25.4 millimeters in an inch and it is often used in science and engineering. It is used in countries that have adopted the metric system.
You may come across millimeters when measuring the size of electronic components, jewelry or even the thickness of a fingernail.