Principle of operation and effect of an equatorial mount, assuming the subject is far enough that parallax is negligible, by CMG Lee. The globe image is from <a class="external free" href="https://commons.wikimedia.org/wiki/File:Eratosthenes_measure_of_Earth_circumference.svg">http://commons.wikimedia.org/wiki/File:Eratosthenes_measure_of_Earth_circumference.svg</a> , telescope from <a class="external free" href="https://commons.wikimedia.org/wiki/File:Astronomy_telescope_on_equatorial_mount-Carl_Zeiss-P5200294-white.jpg">http://commons.wikimedia.org/wiki/File:Astronomy_telescope_on_equatorial_mount-Carl_Zeiss-P5200294-white.jpg</a> and night sky from Stellarium Web.
cmglee, jimht at shaw dot ca, Rama, Stellarium
CC BY-SA 4.0
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