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Remember that co-ordinates in the sky are measued by 2 references RA (right ascension) and Dec (declination)
Dec uses degrees, minutes and seconds and measures how far from the celestial equator the object is, so something directly above the equator of the earth is at 0deg in dec, something halfway between the equator and the South Celestial pole is at -45deg in dec and the South Celestial Pole is at -90deg Dec. Each degree in dec is divided into 60 minutes and each minute is divided into 60 seconds.
RA is measured in TIME and is in Hours, Minutes, and seconds. Think of its as the distance an object moves in the sky in that time period. Obviously an object over the equator moves Faster than one closer to the pole.
The one hour equaling 15deg only applies at the equator. Logically a star sitting directly on one of the poles won't move no matter how long you wait!
Malcolm
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