Lab_3_Phases_of_Moon___Tides_S24

Lab 3: Phases of the Moon & Tides Name: Group Name: Lab 3: Phases of the Moon & Tides The Moon is one of the most noticeable features in the sky. When there is a full Moon, the sky is lit up much more brightly and is up at night. When there is what is called a new Moon, the Moon is not illuminated by the Sun, and is also not up at night—it instead rises in the sky at dawn with the Sun and sets at sunset (you can see the new Moon if you look for it on a clear day). With a little bit of watching, one can see the Moon’s appearance go through a regular pattern of new to waxing to full to waning to new again. We'll explore the cause of these monthly variations today. Credit: Griffith Observatory If you are very observant and watch the Moon over long periods of time, you might notice we always see the same side of the Moon. We'll also explore today why that is! Now, we are going to set up some activities and work in our lab groups to explore why these phases happen and see how tides and the Moon are related. 1

Lab 3: Phases of the Moon & Tides PART A: GROUP MOON ACTIVITY 1. Place the styrofoam ball on the wooden rod. 2. You will be given a flashlight on a stand. The flashlight represents the sun, the white ball represents the moon and your head represents the earth. Imagine your nose as a giant mountain on the Earth's northern hemisphere with a tiny person standing on it, looking at the Moon. 3. Hold the wooden rod with the white ball on it at arm's length in front of you and a little above your head. Slowly rotate your body, keeping the “Moon” in front of you and watching as various parts of the white ball become lit and/or shaded. 4. Switch off with your groupmates, and see how the moon looks different from a different perspective. You won’t be able to see the phases very well when you are not the “Earth”. Questions: A1. Draw diagrams showing the positions of the flashlight, your head, and the white ball (all as seen from the ceiling) for each of the following phases: (3 pts) a. Full Moon (the part of the ball that you can see is fully lit): b. Quarter Moon (the part of the ball that you can see is half lit): c. New Moon (the part of the ball that you can see is not lit): 2

Lab 3: Phases of the Moon & Tides A5. Watch this short video https://www.youtube.com/watch?v=6jUpX7J7ySo and then answer the following questions. What is tidal locking? What does that mean for how we view the Moon on Earth? Is it common or rare that a planet’s moon is tidally locked in our solar system? (4 pts) 4

Lab 3: Phases of the Moon & Tides PART B: TIDES Instructions: 1. Open the Tides Simulator - https://beltoforion.de/en/tides/simulation.php#idStart 2. Change “Look at” from the “Center of Mass” to “Earth” 3. Make sure only “Show Moon”, “Show Ocean”, and “Enable Rotation” are checked (uncheck all others) 4. You can click the Start/Stop button at any time to freeze and restart the simulation Questions: B1. What do you notice about the ocean (blue blob in the simulator) as the Moon orbits around the Earth? (2 pts) B2. Why do you think high and low tides occur on Earth? Draw a picture of the Earth + ocean + Moon. Mark where on Earth there is a high tide and where on earth there is a low tide. It may help to play around with checking and unchecking different options in the simulator. Hint: Be careful you aren’t mixing up Spring/Neap tides with High/Low tides. Ask your instructors if you are uncertain. (4 pts) 5

Lab 3: Phases of the Moon & Tides PART C: NAAP SIMULATOR Instructions: Now, let's try playing with a simulator that demonstrates how the Earth-Sun-Moon geometry gives rise to the phases of the Moon as seen from Earth. A distant view of an observer looking down on Earth as well as a perspective of an observer looking into the sky are used in the simulator. It makes extensive use of materials from the Astronomy Education at the University of Nebraska-Lincoln Website. Go to https://astro.unl.edu/nativeapps/ and download the version of NAAP Labs - v1.1 appropriate for your Operating System. It will install an Application on your computer, which you should be able to open. In the NAAP Labs application, click on 6. Lunar Phases and then read the Background Material. There are helpful animations embedded in the Background Material, which you are encouraged to explore. When you are ready, launch the Lunar Phase Simulator . The items below will help familiarize yourself with the controls and usability features of the simulator. ● The main panel has sunlight, the Earth, and Moon. The Earth and Moon can be dragged with the mouse. ● Below the main panel, there are animation controls. You can 'start animation', or the increment buttons move both the Moon and Earth by the specified time. ● The Moon Phase panel shows the current Moon phase at top right. Drop down menus will jump to a predefined position. Note that the phases, such as crescent and gibbous, are broader than the particular point chosen by the presets. ● The Horizon Diagram panel at bottom right displays the point of view of the observer (and you are a second observer looking down on that observer). The observer's horizon diagram can be dragged to allow for the most convenient viewing orientation.The sun and moon on the globe can be dragged around. ● In the Diagram Options panel, the show angle option shows the Earth-Moon-Sun angle. The phases are technically defined in terms of this angle. ● In the Diagram Options panel, the show lunar landmark option draws a point of reference to more easily observe lunar rotation and revolution. ● In the Diagram Options panel, the show time tickmarks option displays the time of day of the observer. 7

Lab 3: Phases of the Moon & Tides When observing the Moon, one thing we might like to know is when it is visible—what time it sets, rises, and crosses the meridian (or reaches its highest point in the sky). The applet can help find these times. That is the subject of the first question. Questions: C1. Fill in the following table with the times of Moon rise, the moon's highest point in the sky (meridian crossing), and moon set as a function of moon phase. See below for examples. ROUND TO THE NEAREST HOUR . Example: 11:53 AM → 12:00 PM. (6 pts) RISING MERIDIAN CROSSING SETTING WAXING CRESCENT FIRST QUARTER WAXING GIBBOUS FULL 6:00 AM WANING GIBBOUS LAST QUARTER WANING CRESCENT NEW 12:00 PM Example A: What is the meridian crossing (transit) time for a new Moon? Move the Moon to its new position. Rotate the Earth until the Moon is centered on the meridian (the observer should be located on the earth directly facing the Moon). For finding transit times, it helps to change the perspective of the horizon diagram (by clicking and dragging on it) so that we are looking straight down on the diagram. Note that the transit time of the new Moon is 12:00 PM (noon). Complete the rest of the meridian times in the table above. Example B: What is the setting time for a full Moon? First we move the Moon to the full position by dragging it, or selecting "Full Moon" in the phase name drop-down list. Next, click on and rotate the Earth while keeping an eye on the horizon diagram in the lower right corner. Rotate the Earth until the Moon just disappears below the western horizon. You should verify that this occurs at 6:00 AM. Complete the rest of the rising and setting times in the table above. 8

Lab 3: Phases of the Moon & Tides C5. The most recent full Moon occurred on Jan 25. What is your best estimate of the date of the full Moon in March 2024? State your answer in terms of a range of dates that could be consistent with your data (such as Mar 3 to Mar 13; providing a range is also an estimate of your observational uncertainty. Think carefully about how large the range should be. Does your answer to #C4 translate to you knowing exactly the date of the February full moon? How does this uncertainty grow as you project out two months from Janunary, to March?). Provide a detailed explanation of your reasoning. (4 pts) 10