Declination is measured as an angle.

• There are 360 degrees of arc in a circle.
• Each degree of arc is subdivided into 60 minutes of arc.
• Each minute of arc is further subdivided into 60 seconds of arc.

Example: The North Celestial Pole is at a declination of 90 degrees of arc.

Example: The South Celestial Pole is at a declination of - 90 degrees of arc.

Example: A star halfway between the Celestial Equator and the North Celestial Pole would be at a declination of 45 degrees of arc.

Example: If an object is seen to move from a declination of 45 degrees to a declination of 45 degrees, 3 minutes, then the object is moving toward the North Celestial Pole and away from the Celestial Equator.

Right Ascension is measured in terms of units that are related to time through the rotation of the earth.

Example: If you point a telescope at an object that is at zero Ascension and do not adjust it, the earth's rotation will change where it is pointed. After two hours and thirty minutes, the telescope will have turned to point at a location whose right ascension is 2^h30^m.

Notice that the earth turns in a direction that is counterclockwise when viewed looking down from above the North Pole. The rotation carries the direction of a fixed telescope towards the east. Thus, the right ascension increases going eastward.

The north-south line that is at zero Ascension is called the Vernal Equinox Line.

Example: The star Betelgeuse is at a declination of 7 degrees and 24 minutes or 7°24' and at a right ascension of 5^h52^m.