Compass rose

A compass rose or compass star, sometimes called a wind rose or rose of the winds, is a polar diagram that shows the directions we use to find our way. It displays the four main directions, called the cardinal directions: north, east, south, and west. These directions help us understand where we are and where we are going.

You can find compass roses on many tools that help with navigation. They appear on compasses, including magnetic ones, which show which way is north using a magnet. They are also used on maps, like those with compass rose networks, and on monuments that celebrate navigation.

Compass roses are very important in many navigation systems. They are used in nautical charts for ships, non-directional beacons (NDB), VHF omnidirectional range (VOR) systems for airplanes, and even on modern satellite navigation devices such as the "GPS". These tools help people and vehicles move safely from one place to another.

Types

Most groups of people know four main directions, often named after local features like hills or the sea, or after celestial bodies like the sun. These directions help people find their way.

The ancient Greeks had different systems for directions and winds. Over time, these mixed, and wind names began to mean directions. Scholars like Aristotle and Timosthenes created systems of winds to help with navigation. The Romans later used and changed these systems, using Latin names.

The sidereal compass rose uses the positions of stars to mark directions. Arab navigators in the Red Sea and Indian Ocean used a 32-point system based on stars before the year 1000. In the Northern Hemisphere, the Pole Star, Polaris, helped mark north and south, while the Southern Cross was used in the Southern Hemisphere.

In Europe, seafarers made their own 8-wind system using names from Mediterranean languages. This system was later expanded to 32 points, with special names for the main directions and combinations for the others.

Depiction on nautical charts

In old maps from the 1300s, compass roses were simple lines showing directions. These lines were colored to show different wind directions. One of the first fancy compass roses was drawn by Cresques Abraham from Mallorca in his Catalan Atlas from 1375.

Later, map makers added many fancy compass roses to their charts. They used special signs to show north, like a star or an arrow. Some even used a cross to point toward Jerusalem. Compass roses were also drawn on special ship boards to track directions.

Modern depictions

A modern compass rose has two rings, one inside the other. The outer ring shows the true directions, and the inner ring shows magnetic directions. True north is where the North Pole is on Earth, and magnetic north is where a compass needle points. These directions can be different, and this difference is called variation.

Most modern compasses show eight main directions, like North, Northeast, East, and so on. Some maps and signs use fewer directions, such as just North, East, South, and West. Airports often use a compass rose with twelve directions to help with airplane compasses. There are also compass roses with sixteen or thirty-two directions for very exact locations.

Use as symbol

The compass rose is used as a symbol in many places. For example, the NATO symbol uses a four-pointed rose, and Outward Bound uses it as a logo for schools around the world. An 8-point compass rose was the logo of Varig, a big airline in Brazil, and it is also a feature in the logo of the Seattle Mariners Major League Baseball team.

Other groups use it too, like the Hong Kong Correctional Services, the worldwide Anglican Communion of churches, and IBM for its System/360 products. It is also the logo of Spain’s distance learning university, UNED, and appears on the seal and flag of the Central Intelligence Agency in the United States. The blog LessWrong also uses a compass rose as its logo.

In popular culture

The Compass Rose is a book of short stories written by Ursula K. Le Guin in 1982.