Compass rose
From Free net encyclopedia
| Image:Modern Nautical Compass Rose.png |
| Image:Jfader dryden.jpg |
A compass rose or wind rose, is a figure displaying the orientation of the cardinal directions, north, south, east and west on a map or nautical chart. Naming all 32 points on the rose is called boxing the compass. A fleur-de-lis figure, evolved from the initial T in the north wind's name Tramontana, is sometimes used to indicate the north direction. Similarly, on old maps the east was marked with an L for Levante, or with a + indicating the direction of Jerusalem from the point of view of western Europe's countries.
The "rose" term arises from the fairly ornate figures used with early compasses. Today the use and idea of a compass rose is found on or featured in almost all navigation systems, including nautical charts, NDB and VOR systems, some GPS sets and similar.
The contemporary compass rose appears as two rings, one smaller and set inside the other. The outside ring denotes true cardinal directions while the smaller inside ring denotes magnetic cardinal directions. True north refers to the geographical location of the north pole while magnetic north refers to the direction towards which the south pole of a magnetic object (as found in a compass) will point. The angular difference between true and magnetic north is called variation, which varies depending on location. The angular difference between magnetic heading and compass heading is called deviation which varies by vessel and it's heading.
HMS Compass Rose is the name of a fictional Royal Navy corvette in the novel The Cruel Sea.
External links
Template:Water-stubca:rosa dels Vents
de:Himmelsrichtung
es:Rosa de los vientos
fr:Rose des vents
he:שושנת הרוחות
it:Rosa dei venti
pl:Róża_wiatrów
pt:Rosa dos Ventos