How do you use Right Ascension and Declination to find objects in the sky?

If you know these coordinates for an object, you just use a sky atlas to look up the sky position. But to use these coordinates on any given night, you need to know your local sidereal time, and your latitude. The 'LST' tells you which RA great circle is on your north-south line that passes through your zenith. Your latitude and the declination tells you where to look along this 'meridian' to get to the declination. It's a bit complicated and you should get a book on amateur astronomy to go over the details.


Copyright 1997 Dr. Sten Odenwald
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