Hi all.(adsbygoogle = window.adsbygoogle || []).push({});

I have been looking for a formula that gives me the angular separation of two stars.

So far I just found this one :http://www.skythisweek.info/angsep.pdf

but it uses the RA and DEC of the 2 stars, and I need to use the hour angle and DEC. Is it the same thing? Do I just replace HA by RA?

Also I need the equation that gives me the angular separation given the altitude and azimuth of two stars. Can I use the same equation by replacing RA by azimuth and so on?

My goals is to see if the angular distance between two stars given the RA, DEC is different from the angular distance given the ALT, AZ. I think it should be the same but I want to prove it. Also I want to know how that distance (given the ALT, AZ) changes over time. Does it stay the same or does it change?

I would appreciate answers but I really need the equations for a computer code.

Thank you

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# Angular separation of 2 stars

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