Polar

Quadrant Possibilities of use An easy way to determine geographic latitude is to measure with your palms. The palm of the outstretched hand is approximately 10° wide. At 50º north latitude, the Polar Star is at a height equal to the width of 5 hands above the horizon, at the North Pole (90 ° north latitude)

the Polar Star is exactly overhead (that is, forms a right angle with the horizon), and the height from the horizon the zenith here will be 9 palms wide.

At the equator (0° north latitude), the North Star is below the northern horizon. The quadrant is the simplest navigation tool that can measure angles up to 90° (a quarter circle). Travelers and sailors used the quadrant to determine the geographic latitude of an area.

To do this, they measured the angle at which the North Star is located to its projection on the horizon line.

Knowing the latitude of the company allowed the sailors to determine how many kilometers to the north or south they still needed to sail in order to come to your home port
Credit - space.com - astrologyinstars - wikkipedia