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EspañolBEARING (NAVIGATION)
In navigation, a 'bearing' is the clockwise angle between a reference direction (or a datum line) and the direction to an object. Unless otherwise specified, the reference direction is generally understood to be magnetic North, in which case the term ''compass bearing'' is also used.
If navigating by gyrocompass, the reference direction is true north, in which case the terms ''true bearing'' and '' geodetic bearing'' are used. In stellar navigation, the reference direction is that of the North Star, Polaris.
Generalizing this to two angular dimensions, a 'bearing' is the combination of antenna azimuth and elevation required to point (aim) an antenna in a given direction. The bearing for geostationary satellites is constant. The bearing for polar-orbiting satellites varies continuously.
Moving from A to B along a great circle can be considered as always going in the same direction (the direction of B), but not in the sense of keeping the same bearing, which applies when following a rhumb line. Accordingly, the direction at A of B, expressed as a bearing, is not in general the opposite of the direction at B of A (when traveling on the great circle formed by A and B). For example, assume A and B in the northern hemisphere have the same latitude, and at A the direction to B is eastnortheast. Then going from A to B, one arrives at B with the direction eastsoutheast, and conversely, the direction at B of A is westnorthwest.
Bearings are in these terms 0°= north, 45°=Northeast, 90°= East, 135°=southeast, 180°= South, 225°= Southwest, 270°= West, 315°= Northwest and 360°= North.
★ Track (navigation)
★ webpage with program to calculate Distance & Bearing
★ Calculate distance and bearing between two Latitude/Longitude points and much more
If navigating by gyrocompass, the reference direction is true north, in which case the terms ''true bearing'' and '' geodetic bearing'' are used. In stellar navigation, the reference direction is that of the North Star, Polaris.
Generalizing this to two angular dimensions, a 'bearing' is the combination of antenna azimuth and elevation required to point (aim) an antenna in a given direction. The bearing for geostationary satellites is constant. The bearing for polar-orbiting satellites varies continuously.
Moving from A to B along a great circle can be considered as always going in the same direction (the direction of B), but not in the sense of keeping the same bearing, which applies when following a rhumb line. Accordingly, the direction at A of B, expressed as a bearing, is not in general the opposite of the direction at B of A (when traveling on the great circle formed by A and B). For example, assume A and B in the northern hemisphere have the same latitude, and at A the direction to B is eastnortheast. Then going from A to B, one arrives at B with the direction eastsoutheast, and conversely, the direction at B of A is westnorthwest.
Bearings are in these terms 0°= north, 45°=Northeast, 90°= East, 135°=southeast, 180°= South, 225°= Southwest, 270°= West, 315°= Northwest and 360°= North.
| Contents |
| See also |
| External links |
See also
★ Track (navigation)
External links
★ webpage with program to calculate Distance & Bearing
★ Calculate distance and bearing between two Latitude/Longitude points and much more
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