Assorted notes on various nautical language systems.
- Zenith: The imaginary point directly above a particular location, opposite to the apparent gravitational force at that location.
- Azimuth: The angle offset between the north vector and target's vector on the horizontal plane.
- Longitude: The east-west position of a point on the Earth's surface.
- Latitude: The north-south position of a point on the Earth's surface.
- Nautical Mile: Defined as 1852 meters, or one minute of angle along a meridian on the Earth.
- LAN: Local Apparent Noon.
- NSL: Noon sight latitude.
- GHA: Greenwich hour angle.
- Sun altitude offset: 4 seconds off is equal to 1 nautical mile.