Sprial Galaxy, Messier 101, with right ascension, declination explanations

http://www.seds.org/messier/m/m101.html

Right Ascension	14 : 03.2 (h:m)
Declination	+54 : 21 (deg:m)
Distance	27000 (kly)
Visual Brightness	7.9 (mag)
Apparent Dimension	22.0 (arc min)

Right Ascension --> Longitude
Declination--> Latitude

• An object on the celestial equator has a declination of 0°.
• An object at the celestial north pole has a declination of +90°.
• An object at the celestial south pole has a declination of −90°.

For "right ascension, the zero point is known as the first point of Aries, which is the place in the sky where the Sun crosses the celestial equator at the March equinox."

"Since a complete circle has 360 degrees, an hour of right ascension is equal to ¹⁄₂₄ of this, or 15 degrees of arc, a single minute of right ascension equal to 15 minutes of arc, and a second of right ascension equal to 15 seconds of arc.

Earth's equator, as shown below