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Observation - The Night Sky
The night sky is full of objects to view. A telescope is not necessary to view some of the more prominent objects, but first it is important to introduce the most important feature: the stars.

The stars appear to form a sphere surrounding the Earth, so it is not by accident that it is named the Celestial Sphere. However, in reality there is no sphere, and the stars are actually in a variety of distances from the Earth. It is also important to understand that all of the stars visible in the night sky are a part of our galaxy - the Milky Way. The most distant stars make up a faint band of our galaxy that is viewable from the darkest locations.

In order to help find our way around the night sky, various groupings of stars are identified as constellations. These constellations make up mythic characters like Pegasus, Andromeda, and Orion for the northern hemisphere, and objects like Telescopium, Tucana and Crux for the southern hemisphere.

In total, there are 88 constellations. With the exception of the constellations of the Zodiac, there are no specific arrangements to the constellations. For more information on the Zodiac, click here.

Because the Earth is tilted by 23.45º, the northern hemisphere (United States, Canada, Europe, Asia, and Russia) can see some of the southern hemisphere (Australia, New Zealand, South America, Antarctica and the southern parts of Africa) stars and visa versa, it can be difficult to differentiate what can and cannot be seen from your exact location so please consult your local almanac.

I have divided the sky into the northern and southern hemispheres: For the location of the northern hemisphere celestial sphere, I chose San Francisco, California. For the southern hemisphere, I chose Sydney, Australia.

These pages are designed to introduce you to the night sky, but I highly recommend a good star chart or computer software star charting program to help increase your familiarity. Of course, nothing takes the place of actually stepping outside and looking for yourself!

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