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ASP: Miranda: A Jigsaw Puzzle World

The Universe in the Classroom

Miranda: A Jigsaw Puzzle World

Activity Corner

Constellation Activities

by John R. Percy, University of Toronto

Constellations are star patterns on the sky — celestial "connect the dots'' activities that the ancients used to help them keep track of the heavens. Today, astronomers have given constellations another (but related) meaning; they are regions of the sky, defined by boundaries, like countries on the Earth. Every star or galaxy we see can then be located on one of the 88 constellations into which we have divided the sky (coincidentally, the same number as there are keys on the piano.) Each of the 88 regions takes its name from the best-known star group or picture in that region, so the constellation Orion is the sector of the sky that includes the easily recognized star-pattern of Orion the Hunter.

Usually, the stars in a constellation have no physical connection with each other. They are at quite different distances from Earth, and it is only by accident that we see them in the same general direction on the "dome'' of the sky.

Different civilizations have seen very different patterns among the stars, inventing different constellations and attaching their own characteristic stories to them. Indeed, the constellations are like a cosmic Rorschach Test, by which cultures put their own psychological imprint on the heavens. Most of our constellations have been passed down from the ancient Greeks and Romans, although a few were invented in later times when European seafarers first mapped the Southern sky.

Probably the best known constellation is Ursa Major, a large pattern of stars that represents a great bear. Within Ursa Major, seven stars make up a smaller pattern (or "asterism'') called the Big Dipper.

Memorizing the constellations from a book and then trying to find then outside can be a very frustrating experience to most students. Here are a series of activities to enhance learning, teaching, and enjoying the constellations.

Visit a Planetarium

The best place to learn the constellations is where the ancients learned them — outside on a clear, dark night under the dome of the sky. For a variety of reasons — not the least of which is light pollution from our cities — this learning experience is not practical for most classes. An excellent alternative is your local planetarium, where a complex projection instrument simulates the sky. Most planetaria have a regular program for school visits or can set one up if you request it in advance. If you are not sure where the closest planetarium is, call a nearby science museum or college physical science department.

Constellation Stories

An interesting classroom or homework activity is to have your students investigate the stories attached to the different constellations. This can be particularly rewarding if it can be connected with the study of myths and legends from around the world in another course.

Some good references for constellation stories include:

Invent a Constellation

To demonstrate that there is nothing sacred about the star patterns after which the constellations are named (and to have some fun), you might have your students invent their own constellations. Provide them with a star chart that does not have the standard constellations marked on it and ask them to find star patterns that appeal to them on the chart and to make up stories to go with them. (The Sky Challenger Star Wheels kit — see below — includes a blank star chart for just this purpose.)

Constellations on Computer

For schools that have microcomputers there are several good programs on learning the constellations, available for such popular machines as Apple, IBM, and Commodore.

Constellation Slides

Although I do not recommend that your students memorize (and be examined on) the appearance of dozens of constellations, it is worthwhile to reinforce the appearance of a few of them. Ursa Major, Orion, Leo, and Pegasus, for instance, are relatively easy to find, and can be useful for locating other constellations or celestial objects. Constellation slides can be a useful visual aid for learning the basic star patterns.

1. Real Constellation Slides

Color slides of the constellations capture the subtle brightness and color differences among the stars, as well as showing their patterns. Commercial constellation slides can be purchased from various suppliers, such as:

You might want to try taking your own constellation slides. This is fairly easy to do, provided you are away from the light pollution of a city. You will need a camera with a time exposure setting, a wide-open lens, fast color film (that means a high ASA number), and a tripod to keep your camera steady. Point your camera at the desired constellation and then expose the film for 20 to 40 seconds. At these short exposure times, you will not have to guide the camera to compensate for the motion of the Earth. An inexpensive cable release may be useful for not rocking the camera as you hold down the shutter button.

Some handy references:

2. Pinhole Constellation Slides

These are fun to make and can be used in standard slide projectors. You will need stiff cardboard such as Bristol Board, sewing pins, and star charts or other diagrams of constellations.

  1. Cut out enough 5 cm by 5 cm (2 x 2 inch) squares of card board for each student.
  2. Have each student choose a constellation and copy the significant stars in the pattern onto a square of cardboard, leaving a barder about 0.5 cm (1/4 ") around the edge.
  3. Depending on the age of the students (and safety considerations) either you or they can then make holes in the cardboard slides for each star using the sewing pin or needle. Make a larger hole for the brighter stars by pushing the pin all the way into the cardboard; use only the point of the pin to make smaller holes for the fainter stars.
  4. Put the slides into the projector and show them on a screen. Remember that to show the constellations right side up, the slide must be turned upside down. On the other hand, students can try their hand at identifying constellations in a variety of orientations.
  5. Younger students can play a game identifying constellations. One or more students can be responsible for learning and telling the stories attached to each constellation. For older students, each group may also want to learn something about the stars that make up the constellation pattern and even about other objects (galaxies, nebulae, double stars, etc.) that can be found within the boundaries of that constellation.

Resources for Learning About the Constellations

Tours of the Night Sky (Designed for home use, to teach the constellations while you are looking at the night sky, includes a sky tour for each season, full transcripts, and seasonal star maps.)

Sky Challenger Star Wheels (Activity kit developed by the Lawrence Hall of Science, with 6 interchangeable star wheels for teaching constellations, including: Invent Your Own Constellations, Native American Constellations Binocular Treasure Hunt and Star Clock.) Available at many museum or science stores.

Burnham, R. The Star Book. 1983, Kalmbach or Cambridge U. Press.

Chartrand, M. Starguide. 1982, Golden Press.

Menzel, D. & Pasachoff, J. A Field Guide to the Stars and Planets, 2nd ed. 1983, Houghton-Mifflin.

Rey, H. The Stars: A New Way to See Them. 1976 Houghton-Mifflin. (A good basic book for the novice.)

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