Goal of the Lesson
To teach students about the different kinds of galaxies in the heavens.
Objectives
Students will be able to describe the different kinds of galaxies. They will write about the different characteristics of our Galaxy.
Background Information
The Milky way Galaxy is our home and our Solar System is in it. There are billions of other stars in the Milky Way. We are only one of them, and a very little and microscopic part in the middle of one of its arms. Our Milky Way is 100,000 light years in diameter. It would take us 100,000 years to travel from one end to the other 100,000 years at the speed of light. We have some neighboring galaxies visible in the southern skies. These are called the Magellanic clouds. The sky has millions of galaxies. In the northern skies we could see Andromeda, as a faint dot. It is the next large galaxy; a little bigger than our own Galaxy. It looks very much like the Milky Way. Looking at other galaxies in the heavens is a good way to learn about the Milky Way. Our Galaxy, the Milky Way Galaxy, is an example of a spiral galaxy. This type of galaxy has arms unwinding from its center. The letters a, b, or c are attached to the letter S (for spiral). The “a” is for a galaxy that has its arms very close together to the nucleus of the galaxy. The Milky Way is an Sb galaxy.
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There are other types of galaxies in the heavens. There are galaxies with a bar crossing its center. These are called bar galaxies. Other galaxies are elliptical in shape. The majority of galaxies are elliptical galaxies. Star are very old in elliptical galaxies. We also find irregular galaxies, with no particular shape. The local group of galaxies are millions of light years away from us. It is impossible to travel to these places. Waves tell us much information about these galaxies.
In the classroom we constructed a model of our Galaxy. We placed the Solar System in it.
Materials
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Wire
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Metal rods 1/4”
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pulleys
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sparkles
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rope
Students will give shape and form to the Milky Way Galaxy and will place it in the center of the school for all to admire. The structure is simple and lends itself for a good lesson of integrated material: math, science, language and a good portion of art and mechanics. The rods have to be shaped and tied with wires to hold them together. Its shape is that of a spiral galaxy. The center core is round like a ball. This is the place where most of the mass is. The arms of the spiral come out from the core. Here, on the arms, we tie more wires giving it shape, body and form. Students really enjoy doing this type of activity. Most of the activities that we have talked about in this unit were video taped. Students love to be video taped. In our experience students work with more concentration when they know that they are being video taped or recorded. They have a sense of importance. Watching them act is wonderful. Also, it is of great benefit for the student to allow them to watch these video tapes. We took many pictures of their activities and were very happy to get a copy of these unexpected vistas.