Milky Way : Galactic Quadrant

The Milky Way is the galaxy that contains the Solar System.  It is a barred spiral galaxy containing 200-400 billion stars, with 100,000 light years in diameter, and 1,000 light years thick.  It is estimated to be about 13.2 billion years old, nearly as old as the Universe.

Edwin Hubble, in 1920s observed that the Milky Way is just one of around 200 billion galaxies in the observable universe.

Galactic Quadrant

A galactic quadrant refers to one of four circular sectors in the division of the Milky Way galaxy.

Ancient Mesopotamian formulae spoke of “the four corners of the universe” & ”the heaven’s four corners”;

Biblical Book of Jeremiah echoes this phraseology : “And upon Elam will I bring the four winds from the four quarters of heaven” ( Jeremiah 49:36 )

Galactic quadrants within fictional Star Trek are based around a meridian that runs from the center of the galaxy through Earth’s solar system. 

                                                

Real world :  

Sun as center                                       

Described using ordinals, as               

1^st galactic quadrant                              

2^nd galactic quadrant                         

3^rd galactic quadrant                          

4^th galactic quadrant                         

Star Trek :
Galactic Core as center

Designated by Greek letters, as
Gamma Quadrant   
Alpha Quadrant
Beta Quadrant
Delta Quadrant