In nautical navigation

Navigation

Navigation is the process of monitoring and controlling the movement of a craft or vehicle from one place to another. It is also the term of art used for the specialized knowledge used by navigators to perform navigation tasks...

 the absolute bearing is the clockwise

Clockwise

Circular motion can occur in two possible directions. A clockwise motion is one that proceeds in the same direction as a clock's hands: from the top to the right, then down and then to the left, and back to the top...

 angle between north

North

North is a noun, adjective, or adverb indicating direction or geography.North is one of the four cardinal directions or compass points. It is the opposite of south and is perpendicular to east and west.By convention, the top side of a map is north....

 and an object observed from the vessel. If the north used as reference is the true geographical north

True north

True north is the direction along the earth's surface towards the geographic North Pole.True geodetic north usually differs from magnetic north , and from grid north...

 then the bearing is a true bearing whereas if the reference used is magnetic north then the bearing is a magnetic bearing.

An absolute bearing is measured with a bearing compass.

The measurement of absolute bearings of fixed landmarks and other navigation aids is useful for the navigator because this information can be used on the nautical chart

Nautical chart

A nautical chart is a graphic representation of a maritime area and adjacent coastal regions. Depending on the scale of the chart, it may show depths of water and heights of land , natural features of the seabed, details of the coastline, navigational hazards, locations of natural and man-made aids...

 together with simple geometrical techniques to aid in determining the position of the vessel.

See also

• Relative bearing
  Relative bearing
  In nautical navigation the relative bearing of an object is the clockwise angle in degrees from the heading of the vessel to a straight line drawn from the observation station on the vessel to the object....
  
  
• Bearing
  Bearing (navigation)
  In marine navigation, a bearing is the direction one object is from another object, usually, the direction of an object from one's own vessel. In aircraft navigation, a bearing is the actual compass direction of the forward course of the aircraft...