This type of mount is used in transit telescopes, designed for precision astronomical measurement. This allows the telescope to view the whole sky, but only when the Earth's rotation allows the objects to cross ( transit) through that narrow north-south line (the meridian). Transit mounts are single axis mounts fixed in azimuth while rotating in altitude, usually oriented on a north-south axis. They can cover the whole sky but only observe objects for the short time when that object passes a specific altitude and azimuth. Fixed altitude mounts įixed-altitude mounts usually have the primary optics fixed at an altitude angle while rotating horizontally (in azimuth).
Fixed telescope mounts are entirely fixed in one position, such as Zenith telescopes that point only straight up and the National Radio Astronomy Observatory's Green Bank fixed radio ' horn' built to observe Cassiopeia A.
