Galactic quadrant

A galactic quadrant or quadrant of a galaxy called one of four circular sectors as the division of the Milky Way.

Quadrant of the galactic coordinate system

In astronomical practice, the galactic quadrants are defined in the galactic coordinate system by the sun as a pole (for practical reasons instead of the galactic center ), since all astronomical observations ( of people ) to date come from the earth or the solar system.

Demarcation

Quadrants are designated by ordinal numbers, for example " first galactic quadrant ", " second galactic quadrant " or " third quadrant of the galaxy ." Seen from the north, the galactic poles arise from 0 degrees (°) as a starting beam passing by the sun and the galactic center. After that, the quadrants are defined as follows:

Visibility of quadrant

Due to the orientation of the Earth in relation to the rest of the galaxy, the second galactic quadrant is visible from the northern hemisphere in the first place, while the fourth is usually only visible from the southern hemisphere. Therefore, the classification according to quadrant is usually more practical for amateur astronomers, however, international astronomical organizations are therefore not bound to the earth horizon.

From Earth, you may ( as a rough guide ) recognize the limitations of the quadrants based on the following major constellations:

• After 0 ° you look, when you look in the direction of the constellation Sagittarius.
• After 90 ° you look, when you look in the direction of the constellation Cygnus.
• After 180 ° you look, when you look in the direction of the constellation of Fuhrmann.
• After 270 ° you look, when you look sails of the ship in the direction of the constellation.