Celestron 11074-XLT, Instruction Manual

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2. Slew the telescope to one of the original alignment stars, or another bright star if the original alignment stars are no longer
in a convenient location. Press the
Align button and use the Up/Down buttons on the hand controller to select Alignment
Stars from the list.
3. The hand control will ask you which of the original alignment stars you wish to replace. Use the Up/Down buttons to select
the desired star and press
Enter.
4. Once again center the star in the finderscope and press Enter.
5. Then center the star in the eyepiece and Press Align.
6. Repeat the process on a second alignment star.
Display Align – the user can now display the polar alignment error in the RA and DEC axes. These values show how close
the mount is pointed at the celestial pole based on how accurately the user centered the alignment star with the hand control
and with the mount adjustment. To display the alignment error:
1. Press the Align button and use the Up/Down buttons on the hand controller to select Display Align from the list, and press
Enter .
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In each hemisphere, there is a point in the sky around which all the other stars appear to rotate. These
points are called the celestial poles and are named for the hemisphere in which they reside. For
example, in the northern hemisphere all stars move around the north celestial pole. When the
telescope's polar axis is pointed at the celestial pole, it is parallel to the Earth's rotational axis.
Many methods of polar alignment require that you know how to find the celestial pole by identifying
stars in the area. For those in the northern hemisphere, finding the celestial pole is not too difficult.
Fortunately, we have a naked eye star less than a degree away. This star, Polaris, is the end star in the
handle of the Little Dipper. Since the Little Dipper (technically called Ursa Minor) is not one of the
brightest constellations in the sky, it may be difficult to locate from urban areas. If this is the case, use
the two end stars in the bowl of the Big Dipper (the pointer stars). Draw an imaginary line through
them toward the Little Dipper. They point to Polaris (see Figure 6-6). The position of the Big Dipper
changes during the year and throughout the course of the night (see Figure 6-5). When the Big Dipper
is low in the sky (i.e., near the horizon), it may be difficult to locate. During these times, look for
Cassiopeia (see Figure 6-6). Observers in the southern hemisphere are not as fortunate as those in the
northern hemisphere. The stars around the south celestial pole are not nearly as bright as those around
the north. The closest star that is relatively bright is Sigma Octantis. This star is just within naked eye
limit (magnitude 5.5) and lies about 59 arc minutes from the pole.
The north celestial pole is the point in the northern hemisphere around which all stars appear to rotate. The
counterpart in the southern hemisphere is referred to as the south celestial pole.
Definition