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ALIGNMENT WITH THE CELESTIAL POLE
Your refracting telescope oers the advantage of being installed on an equatorial mount. is mount
allows the rotation of the Earth to be oset during observation.
To make the most of this convenient feature, you will need to use a setting called: polar alignment.
Objects in the sky appear to rotate around the celestial poles. (In reality, celestial bodies are xed in
place, and their apparent rotation is caused by the rotation of the Earth). In one 24 hour period, the
stars complete one full revolution of the pole according to the concentric circles of which the pole is
the centre. By aligning the right ascension axis of the refracting telescope with the northern celestial
pole (or for observations in the southern hemisphere, the southern celestial pole), you can follow the
celestial bodies by rotating the refracting telescope around a single axis - the right ascension axis!
POLAR ALIGNMENT
Polar alignment consists of aligning the right ascension axis of the refracting telescope (A - FIG 1)
with the rotation axis of the Earth.
To do so:
1. Set the mount at the desired level (horizontally), by adjusting the height of the legs.
2. Unscrew the azimuth lock (8) from the baseplate (7), so that the refracting telescope and its mount
can turn horizontally. Turn the refracting telescope until the right ascension axis (A) points north. Use
a compass or locate the North star to help you.
3. Determine the latitude of your observation site using a road map, atlas, or via Google Maps . Use the
adjustment screws (21) to turn the mount of the refracting telescope, so that the marker (23) indicates
the latitude of your observation site on the coordinate ring (22)
Your refracting telescope is now set up and suciently well aligned with the celestial pole for visual
observations.
