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5: Measuring and Mapping the Sky

  • Page ID
    25246
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    Observation and recording what we see in an accurate way is the foundation of all scientific knowledge. Map making is one of the oldest scientific activities, it certainly predates written language and recorded history by many millennia. The oldest known drawings of constellations are on clay tablets more than 15,000 years old; maps of the lunar phases date back more than 30,000 years. Even though map making is a very ancient activity, it is not a natural one. Map making is an acquired skill that requires practice, but with the use of simple tools even very young students can do a remarkable job of it.

    Maps are also great teaching tools. Keep in mind that younger students are very visual learners. Young students who possess only basic literary and logical skills often find it difficult to follow ideas or arguments that are presented through language – this is also a fundamental problem for the ESL student.

    Maps put information in an easy to understand visual format, as well as putting information into context which helps the student build a mental framework. Helping students to integrate new knowledge in with what they already know can be a daunting challenge. Map making helps make this process easier, and more effective.

    • 5.1: Altitude and Azimuth – Your Place in the Sky
      This activity is also best conducted in the daytime, and can even be done indoors although it works best out in the school yard or playground. After your students learn to use these tools properly, the Being an Astronomer section will give them an activity they can use to try their new skills out after dark at home in their own back yards.
    • 5.2: Measuring the Nightly Path of the Moon
      This activity is simple enough in concept, and can be conducted any night the Moon is visible for several hours in the sky; practically speaking, this works best in the week between first quarter moon and full moon. Students will be taking an altitude and azimuth measurement of the Moon every hour for 4-5 hours. At least four separate measurements are needed for best results. The Moon’s diurnal motion will be plotted on a simple graph after the measurements are taken.
    • 5.3: Measuring the Moon’s Orbital Motion
      Try activity 9 again, but this time measure the Moon’s position in altitude and azimuth at the same time for several days beginning shortly after new moon, you will find that the graph is similar except that the points move eastward showing orbital motion and that the phase will change over several days! In order for this activity to be successful, students must remember to take their measurements at approximately the same time every day.
    • 5.4: Measuring the Earth with Eratosthenes
      An ancient Greek astronomer named Eratosthenes was the first man to measure the size of the Earth accurately. His method was very simple: he measured the angle made by a shadow cast from a vertical stick in two different cities on the same day and time. With the help of another teacher, you can recreate Eratosthenes’ experiment and your students can measure the size of the Earth for themselves! All you will need is two yardsticks, a protractor, a magnetic compass, and a bit of string.
    • 5.5: Mapping the Constellations
      The device that we will build is called a pantograph. This device is based upon an old-fashioned drawing tool that allowed the user to copy down drawings and make them different sizes without distortions. We will use our pantograph to accurately copy the constellation patterns that we see in the sky. All we need to do is measure distances between points with a ruler, and copy down angles!


    This page titled 5: Measuring and Mapping the Sky is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Daniel E. Barth via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.