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I'm parsing FITS files for a project based on data from a telescope. These files include 'DEC', 'RA' and lat long values. I understand roughly the concept of celestial coordinates and I assume that these values are sufficient to calculate the direction that the telescope is facing and the angle that it's at but my trigonometry is not up to the task.

I am using astropy for the project so any answers which reference that would be great.

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What do you need to calculate? DEC and RA are the celestial coordinates, so they are "where" the telescope is pointing at. – Envite May 21 '14 at 10:34
In order to determine the position of the telescope relative to the earth from RA and declination, you need to know the latitude and longitude of the telescope and the date and time. *** A new question by a different user, @ruadath, has appeared here… . You might want to track that question. – outis nihil May 21 '14 at 19:32
Especially, if it is a space telescope, it is a mess :) you need much more than two coordinates. – Py-ser May 23 '14 at 5:16

PyEphem will get you Alt, Az from RA, Dec, Lat, Lng, Date, Time, and Elevation

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