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Milky Way Galaxy
The Sun and all the stars we can see in the night sky belong to the Milky Way Galaxy. It got its name because ancient people thought it looked like milk spilled by a goddess while she fed her baby. This glow of light actually comes from a cluster of billions of stars. Our entire galaxy is made up of over 200 billion stars. Even though they seem like they are close together, these stars are very far from each other. Since the earth and the solar system are part of the Milky Way, we can't take a picture of it. so to help us figure out what it looks like, we take pictures of other galaxies. If we could travel into space and see our galaxy, it would look like an enormous and dazzling spiral pinwheel of lights stretching out over 100,000 light-years. Our entire galaxy is actually turning in space at a high rate of speed. As a matter of fact, did you know that the Sun and all of the planets are zooming around the center of it at 250 kilometers per second? That seems pretty fast but the entire galaxy itself is traveling through space at a speed of about 1 million miles per hour. The galaxy that earth is located in is defined as a spiral galaxy because of its shape. Different kinds of galaxies The Milky Way Galaxy was the only known galaxy until 1924. In that year, astronomer Edwin Hubble was able to prove that there were several distant galaxies. We now know that galaxies can be many differrent shapes and sizes. A galaxy is generally classified by its shape and can be elliptical or spiral. Elliptical galaxies are egg-shaped and usually contain all old stars and very little gas. Spiral galaxies contain relatively young stars and more gas. |
