Finding the North Celestial Pole

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 13). The position of the Big Dipper changes during the year and throughout the course of the night (see Figure 12). 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 13). 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.

Definition

Figure 12 - The position of

the Big Dipper changes

throughout the year and the

night.

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.

Figure 13

The two stars in the front of the bowl of the Big Dipper point to Polaris which is less than one degree from the true (north) celestial pole. Cassiopeia, the “W” shaped constellation, is on the opposite side of the pole from the Big Dipper. The North Celestial Pole (N.C.P.) is marked by the “+” sign.

Using the Setting Circles

Setting Circles are dials (or gauges) for right ascension and declination that allow you to locate celestial objects easily from their coordinates as listed in a star chart or atlas.

1.The declination setting circle (#2) is scaled in degrees and the right ascension setting circle is incremented in minutes. The circles will get you close to your target but not directly on it. Also, the accuracy of your polar alignment will affect how accurate your setting circles read.

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Celestron 80 manual Finding the North Celestial Pole, Using the Setting Circles

80 specifications

The Celestron 80, commonly referred to as the Celestron Astromaster 80, is a popular choice among amateur astronomers and nature enthusiasts alike. This versatile telescope combines portability, ease of use, and impressive optical performance, making it an excellent introduction to the world of astronomy.

One of the primary features of the Celestron 80 is its 80mm aperture. This size allows for a bright and clear view of celestial objects, even in less-than-ideal conditions. The telescope employs a fully coated optical system, which enhances light transmission and improves image clarity. As a result, users can enjoy sharp, detailed views of planets, the moon, and various deep-sky objects such as star clusters and nebulae.

The design of the Celestron 80 is particularly user-friendly. The telescope is equipped with a simple alt-azimuth mount, providing both vertical and horizontal movement. This makes it easy to track objects across the night sky. The mount is also lightweight and portable, making the telescope an ideal companion for on-the-go stargazing adventures or nature observation excursions.

Another standout characteristic of the Celestron 80 is its versatility. It comes with a couple of eyepieces, allowing users to switch magnification levels to suit their viewing preferences. The included finderscope simplifies locating celestial objects, ensuring that even novice users can quickly find and observe various targets.

The Celestron 80 also showcases advancements in technology, including its sturdy, adjustable tripod that ensures stability during use. Additionally, the telescope is designed with user comfort in mind, featuring an adjustable height to accommodate various viewing positions.

For those interested in astrophotography, the Celestron 80 offers several opportunities for capturing images of the night sky. With the proper accessories, users can attach a camera to the telescope, making it a suitable option for wide-field astrophotography.

In summary, the Celestron 80 is an excellent entry-level telescope that offers a powerful combination of features, technology, and portability. Its impressive optical performance, user-friendly design, and versatility make it a favorite among both beginners and seasoned enthusiasts. Whether you wish to observe the craters of the moon or the rings of Saturn, the Celestron 80 is poised to provide an enjoyable and fulfilling viewing experience.