Types of telescopes:
There are three main types of telescopes. The traditional telescope is made up of two lenses with a tube in between them. The furthest lens from your eye is called the objective lens because it is closest to the object you are looking at. These telescopes are called refracting telescopes. When they are small, they are useful because they offer more power than other types of telescopes, but they get too heavy and too awkward if they are very large.
Most larger telescopes are called reflecting telescopes because they use a mirror that reflects images instead of an objective lens. They kind of look like a bucket with a mirror in the bottom. You usually look through a hole on the side of the telescope. These telescopes are an excellent choice once you get into bigger telescopes.
The third type of telescope is called a Cassegrain Telescope. These telescopes combine the refractors with reflectors. They get all the positive benefits from each type, and cancel out most of the negatives. But they are also very expensive. If you can afford a Cassegrain telescope they are the best type to buy. They do have one draw back, and that is they do not look like what people expect telescopes to look like. They do not have long tubes but instead are short and stubby. They have both an objective lens and a mirror.
In the last three astronomy packets we have focused on one part of the sky. We have looked for the constellations Ursa Major, Ursa Minor, Cassiopeia, and the stars Polaris, Mizar and Alcor. All these objects are pretty much in the same area in the sky.
Now we are going to look to a completely different part of the sky to find a very bright constellation named Orion. This constellation is much brighter than the ones we have found so far. Orion was a great hunter. He bragged that he could kill all of the Earth’s wild animals. Gaia, the goddess of the Earth, did not like this. She put Orion in the stars in order to save all the Earth’s precious creatures.
Look for three bright stars in a straight line. This is Orion’s belt. Now using a skymap, find the rest of the constellation. In Astronomy Packet 6 we are going to find some objects within this constellation.
Assignment # 6
Find the constellation Orion.