I am a little confused. I am under the impression that Xephem derives
its AZ/EL data from RA/DEC and Earth position. Strangely, xephem
disagrees with Cartes du Ciel on Polaris' RA/DEC, but agree exactly on
AZ/EL. How could this be?
Also, Cartes du Ciel is very close to data derived at the USNO website
for RA/DEC.
Any clarification would be helpful.
Thanks,
Chris Maness
