There are three kinds of galaxies: elliptical, irregular, and spiral. Elliptical galaxies have most of their stars in a sort of lemon-shaped (elliptical) area. You could make a model of an elliptical galaxy by making a ball of Play-Doh, then rolling it just a little flat in one direction. Irregular galaxies are just a bunch of stars grouped together in no particular shape. You could make a model of an irregular galaxy by dropping a handful of dry rice grains in the center of a plate, then dropping another handful across the whole plate. (And then you'd want to imagine the whole thing in three dimensions instead of flat.)
The third kind of galaxy is the kind we live in--a spiral galaxy. The Milky Way has hundreds of billions of stars scattered around in three main parts: the nucleus, the spiral arms, and the disk. Learn lots more about what kinds of stars are in each of these parts here.
To make your own galaxy art, get a piece of paper, two pencils, and a partner. Have one partner hold a pencil in the center of the paper and spin the page slowly and steadily while the other partner draws lines from the pencil in the center out toward their body. As the paper spins, the lines you draw will make nice curves like the spiral arms of our galaxy!
Next, attach your paper to a piece of black construction paper or card stock. Take a push pin and carefully poke holes through both pieces of paper along your spiral arms. Poke extra holes in the center to make the nuclues. Try to make different sizes of stars with your pin or the point of a sharp pencil. Label the nucleus, the disk, and the spiral arms of your galaxy, then hang it in a window (or hold it up to a glowing computer screen) and check out your beautiful galaxy!
For more on galaxies, check out NASA's galaxy page or at kidsastronomy.com.
How fun! I'm going to have to try this.
ReplyDelete