The Moon Project: Topic 4 – Synodic and Sidereal Months MP–1 The Moon by Mary Barrett1 The Moon is really just one size The light grows larger every day It always stays the same, Exactly as it ought'er, But here on Earth before our eyes, But logic tells us we must say We see it wax and wane. What looks like half is quarter. The new moon we don't see at all, And then there's gibbous on its way But then there is a sliver, To full, the brightest face, The crescent moon is what we call Then swiftly it begins to wane This slice that makes us quiver. 'Til gone without a trace. These changes happen every night; Each month we see each phase The moon intrigues us with its light It truly does amaze. Dear God, It is great the way you always get the stars in the right place. Why can't you do that with the moon? Jeff (a young child) Organization of the Moon Project (Worth a total of 150 points) Part of Project Point Value Specific Requirements are on… Observations and Graphs 30 points MP–2 through MP–4 Teaching of the Lesson 10 points MP–5 Written Reflection on the Lesson 20 points MP–5 through MP–6 Explanations of Concepts (your topic) 60 points MP–7 through MP–11 Completed Lab Activities (all topics) 30 points MP–11 Information, Tables, Graphs and Rubrics Where to find them Grading Rubric for the Explanation of Concepts MP–13 Tables in which to record your observations MP–15 through MP–20 Graphs for you to complete MP–21 through MP–36 Tables of Moon Facts MP–37 through MP–48 Lab Activities for all Four Topics C–73 through C–98 1 Mary Barrett is a school teacher in Berkeley, CA. This poem appeared in the Fall/Winter 1999 GEMS Network News. If you plan to teach elementary or junior high school, check out all the wonderful GEMS (Great Explorations in Math and Science) K–8 teacher’s guides in math and science at http://www.lhs.berkeley.edu/gems/gems.html.MP–2 The Moon Project: Topic #4 – Synodic and Sidereal Months Purpose: This assignment is designed to give you the opportunity to… • become intimately familiar with the various changes that the moon goes through each month and season. • conduct a genuine scientific research project: to make systematic accurate observations and to use those observations to derive scientific conclusions WITHOUT “looking it up” somewhere. • teach a lesson that guides others to discover scientific concepts for themselves. • reflect on your teaching efforts, documenting successes, problems and ideas for improvement. • write clear, complete, well-illustrated explanations of scientific concepts. Questions to Answer for Topic #4 1. The amount of time that the moon is out on any given day (or night) varies considerably. In Chico, the amount of time the moon is out ranges from less than 9 hours to more than 16 hours. We know that the sun is out the longest on the summer solstice (± June 21). After that date, the days gradually get shorter and shorter until the winter solstice (± December 21), the shortest day of the year. After the winter solstice, the days gradually get longer and longer until the next summer solstice. In scientific terms, the number of hours that the sun is out increases and decreases in a cycle with a periodicity of one year. The number of hours that the moon is out also increases and decreases in a cycle. What is the periodicity of that cycle? Is it one synodic month? One sidereal month? One year? Or something else altogether? Use one of your graphs to prove your answer. Why does that cycle have the length that it does? Draw diagrams to illustrate your answers. 2. What do the longest moon days of all moon cycles have in common (this should “fall out” of one of your graphs)? Why? What do the shortest moon days of all moon cycles have in common? Why? What do the average-length moon days of all moon cycles have in common? Why? Draw diagrams to illustrate your answers. 3. The moon, like the sun, travels through the constellations of the Zodiac. How long does it take the moon to go through all of the constellations of the Zodiac? Does it take a synodic month? A sidereal month? A year? Or something else altogether? Why? 4. How do we know that it takes the moon exactly 27 1/3 days to complete a 360° orbit of Earth (a sidereal month)? Hint: one of your graphs should provide the information you need.The Moon Project: Topic #4 – Synodic and Sidereal Months MP–3 Observations to Make for Topic #4 Where to Make Your Observations: The best place to make each observation is in a large open area (a sports field or large parking lot, for example). Required Number of Observations: You must observe the moon on at least 20 different dates; for at least 10 of these observations, you must sketch in the stars and planets that surround the moon. In addition, at least 7 of your observations must be made during the waning phases of the moon.2 BEGIN YOUR OBSERVATIONS IMMEDIATELY. If you have trouble at first, keep trying; it gets easier. Suggested Times of Observations: Be sure to make each observation when the moon is actually out. The time period when the moon is out varies from day to day. Use the moonrise and moon-set times in the “Moon Facts” tables to figure out when the moon will be out. Plan carefully to be able to see the moon in the dark at least 10 times, so that you can see the surrounding stars and planets. Data to Record: Record your data in the given tables. 1. Record the time of each observation. Be sure to include a.m. or p.m. as appropriate. 2. Under “Sketch of Moon,” sketch the moon the way you see it in the sky by blackening the part of the moon that you can NOT see; leave the visible part of the moon white. Be sure to clearly show how the visible portion is “tilted” relative to the horizon (On the data table, imagine the horizon as a horizontal line on the bottom of the page.). 3. In the far right column of the moon observation tables, show the moon and any stars (or planets) that you see around the moon, whether or not you can recognize the constellation. Include in your sketch the apparent distances of these objects from the moon (use “widths of the moon” as your measuring unit). Note: it is easiest to see the stars around the moon when the moon is a crescent. Try to time your 10 observations accordingly. 4. If it is cloudy out or if you forget to look, make a note of that, but do not sketch the moon