September 7, 2020

The azimuth

In order to determine the error of the gyro or magnetic compass by astronomical observation, one must be able to find the true bearing of a celestial body from the observer at any time. By comparing the compass bearing with the bearing calculated at a specific time, one can determine […]
September 7, 2020

The amplitude

An amplitude is the “azimuth” of a heavenly body when it is on the observer’s rational horizon. The angle at the zenith between the prime vertical circle (the vertical circle passing through the east and west points) and the vertical circle passing through the body is called the amplitude of […]