Organization of Economic Cooperation and Development, headquartered in Paris with membership consisting of the world's developed nations. Office of Global Maritime Situational Awareness (OGMSA)It is the United States initiative to establish a world–wid ...
An atmospheric phenomenon, other than clouds, which obscures a portion of the sky from the point of observation. Also called obscuration.
The difference between the true value of some quantity and its observed value. Every observation is subject to certain errors. Systematic errors affect the whole of a series of observations in nearly the same way. For example, the scale of an instrument m ...
A position or fix determined by observing landmarks or other objects to find the position.
1.Ore Carrier.2.Oil-lubricated stern bearing, continuous liner on tailshaft.3.Optical character recognition.
A navigational light which turns on and off in a regular pattern, but is on more than it is off, so the period of light is longer than the period of darkness.