Celestial Coordinates are typically given in Right Ascension and Declination – they are the celestial equivalents in the sky of what longitude and latitude are to the surface of the Earth. Right Ascension is used to denote Eastward or Westerly directions, while Declination measures Northern or Southern directions (like longitude and latitude, respectively).

Right Ascension is measured in hours, minutes, and seconds, because as the Earth rotates, we see different parts of the sky throughout the night. If an object at 6h, 7m, 49s is directly above you, then an hour later it will be at 7h, 7m, 49s… and so on.

Zero hours RA is conventionally the Right Ascension of the sun on the vernal equinox, March 21.

Declination is measured in degrees, arcminutes, and arcseconds. There are 60 arcmin in a degree, and 60 arcsec in an arcmin. The symbols for arcmin and arcsec are the same as for feet and inches.

So your object is 70 degrees, 20 arcminutes, and 30 arcseconds north of the “Celestial Equator” – the projection of the equator on Earth into the sky. The Celestial Equator is the point of 0 degrees Declination, and therefore the North Star is at approximately 90 degrees Declination.

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