Lab 3

Name:________ ______________ Date:________ _________ PHYS 110L Lab # 3 Orbital Motion of the Earth-Moon and Jupiter-Io Systems 1 Learning Objectives: In this lab assignment you will conduct a series of inquiries, using a solar system simulator, about the position and motion of the Earth and the Moon and Jupiter and its moon Io. Equipment: access to https://space.jpl.nasa.gov Please bring a ruler to the lab. Instructions: Please read and follow the steps described below and answer all questions. Part #1 Computer Simulator Setup: Step 1. Go to the website: https://space.jpl.nasa.gov Step 2. In the Targets and Date section, under the Show me drop-down menu, select …the Moon and under the as seen from drop-down menu, select the Sun . Step 3. Under the Field of View section, click the radio button I want a field of view of and change the number of degrees to 0.5 . Step 4. Under the Options section, select -extra brightness and then click the Run Simulator button. Part #2 Exploration of Earth-Moon System: Step 5. The resulting image from running the simulator is what one would see if looking through a special telescope. Question 1: For this image, where is this special telescope located? The telescope is located on the Sun. 1 Modified from Engaging in Astronomical Inquiry , by S. J. Slater, T. F. Slater, and D. J. Lyons, 2010, W. H. Freeman and Company. 1

Question 2: How does the image change if you increase the field-of-view? To answer this, hit the back button on your browser and change the I want a field of view value to be 2 degrees and run the simulator. It zoomed out, so we can see more of the surrounding area. Also, the Moon and the Earth become closer together. Step 6. Now change the field-of-view value back to 0.5 degree and run the simulator. Question 3: What is the exact date of the image given in the upper left-hand corner? 2023 SEP 13 Question 4: Astronomers typically mark images based on the time it currently is in Greenwich, England, called universal coordinated time (UTC). What is the precise time listed on the image? 00:00:00 UTC Question 5: Use a ruler to measure the distance on your monitor or screen between the middle of the Earth and the middle of the Moon. What is the measured distance ? Positive values are measured to the right and negative values to the left . You do not need to know the exact number in kilometers or miles, but simply a ruler measurement ( e.g. inches, mm, etc. ) so that you can compare other measurements you will make later. Record the distance here with the correct sign (+ or −). Distance: -1.2 in Step 7. Use the browser’s back button to return to the Solar System Simulator homepage. Now, advance the time by one hour (under the Targets and Date section), run the simulator, and determine the new distance between the Earth and the Moon. Record the distance here with the correct sign (+ or −). Distance: -1.1 in 2

Step 14. Use the browser’s back button to return to the Solar System Simulator homepage. Now, advance the time by three months from when you started, run the simulator, and determine the new distance between the Earth and the Moon. Record the distance here with the correct sign (+ or −). Distance: -0.4 in Question 6: How long does it take for the Moon to orbit the Earth based on your observations? Recall that the orbital period is the time required for the Moon to complete one full orbit of the Earth ( i.e. the Moon returns to its starting point). Explain. Around 1 month Part #3. Exploration of Jupiter-Io System: Step 15. Consider the research question. “How long does it take one of Jupiter’s moons to orbit Jupiter?” Set the Solar System Simulator to observe Jupiter from the Sun, where Jupiter takes up 10% of the image, and measure the distance between Jupiter and its moon Io shown on the simulator image. On the Solar System Simulator homepage, set Show me to be Jupiter and click on the radio button I want the body to take up ___ percent of the image width . Set the percent value to 10% and then click on the Run Simulator button. Measure the distance between the middle of Jupiter and Io and record the distance measurement with the correct sign (+ or −). If Io is not visible due to it being behind or in front of Jupiter, please add a day to your starting time and try again. Distance: -.08 in 4

Step 16. Use the browser’s back button to return to the Solar System Simulator homepage. Now, advance the time by one day and record the distance between Jupiter and Io. Record the distance here with the correct sign (+ or −). Distance: Step 17. Use the browser’s back button to return to the Solar System Simulator homepage. Now, advance the time by two days from when you started and record the distance between Jupiter and Io. Record the distance here with the correct sign (+ or −). Distance: +1.3 in Step 18. Use the browser’s back button to return to the Solar System Simulator homepage. Now, advance the time by three days from when you started and record the distance between Jupiter and Io. Record the distance here with the correct sign (+ or −). Distance: -2 in Step 19. Use the browser’s back button to return to the Solar System Simulator homepage. Now, advance the time by four days from when you started and record the distance between Jupiter and Io. Record the distance here with the correct sign (+ or −). Distance: +2.6 in Step 20. Use the browser’s back button to return to the Solar System Simulator homepage. Now, advance the time by five days from when you started and record the distance between Jupiter and Io. Record the distance here with the correct sign (+ or −). Distance: -2.5 in Step 21. Use the browser’s back button to return to the Solar System Simulator homepage. Now, advance the time by six days from when you started and record the distance between Jupiter and Io. Record the distance here with the correct sign (+ or −). Distance: +2.25 in 5