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Astronomy 104: Stellarium Assignment 1(Estimated time for completion between 1-2 hours)TURN IN ANSWERS ON THESE SHEETS0. Be sure to download Stellarium version 0.15.2 or later (I am using 0.18.2). Instructions to do so are available on the class website.1. Launch Stellarium. The view you see will depend on the actual time you start the program. Let’s begin by taking a quick tour through the program’s controls.2. Move the mouse to the lower left side of the Stellarium window and click your mouse; as you do this, you should see the left sidebar slide into view. The icons on this sidebar will look something like this:01905000The top icon opens the Location window which is used to specify the viewing location (you can also use the F6 key to open this window).The second from top icon opens the Date/Time window which allows you to change the time of obserervation (you can also use F5 to open this window).The third icon from the top opens the Sky and Viewing Options window (you can use F4 to open this window).The fourth icon from the top opens the Search window (or F3).The fifth icon from the top opens the Configuration window (F2).The sixth icon from the top opens the Astronomical Calculations window (F10).And the bottom icon opens the Help window (F1)In this assignment, we will only be using the Location, Date/Time and Help windows.Whenever in doubt of about commands, use the Help window (F1).3. Let’s start by specifying a time and location of observation. Open the Date/Time window (with the mouse or F5). You will see the following window:Enter the date and time specified in the figure above (Feb 21, 2016, and approximately 12:00:00). The seconds will advance at a normal rate as you enter the time, but that is ok. Close the window by clicking the ‘X’ in the upper right.Now, open the Location window (mouse or F6); you should see the following window:In the Search area (where the hand lens icon is visible and immediately above the ‘Reset Location List’ button), enter ‘Ann Arbor’. Then click on Ann Arbor, United States from the selection window in the top right and select Ann Arbor. You should see the names in the status bars in the lower right region of the window update. Close the window (‘X’ in upper right). You should now see a nice view that shows the Sun in a clear blue sky.4. When you are viewing the sky, you can always move your view around with the arrow keys; move left or right until you are looking due South (the directions are shown along the horizon). You should see the Sun almost due South. Move up (up arrow key) to center the Sun in your view and then click on the Sun. You should see a long listing of information in the upper left of the view. Search for the line that says ‘Az/Alt’ (for azimuth/altitude). What is the altitude of the Sun (answer in the space below)? Be sure to note the units. You can erase the info listing by two-finger clicking your mouse.5. Now, ‘turn off’ the sky by typing the ‘A’ key (lower or upper case is fine). The sky should turn dark and you should see many other objects now other than the Sun. What planets are visible in the vicinity of the Sun? Again, use the left/right arrows to move your view in the east/west directions (and up/down arrows too as needed). 6. Open the Date/Time window again (clicking on the icon or F5). Keep all values the same except change the hour to ‘6’. What planets are now visible in the sky? What prominent star is located due South of your location?7. Now advance the date by one sidereal day. This can be done with ‘Option =’ on a Mac, and ‘Alt =’ on a PC. What will happen is that the stars will not move but any objects, such as a planet that is moving relative to the stars, will appear to move. Do this ten times. Use the bright star you noted in section 6 above as a reference point. Describe how the two planets move.8. Repeat the sidereal day advance command (Option = or Alt =) numerous times until the brighter of the two planets changes direction. Where is it located relative to that bright star you noted in Section 6? Continue to move by units of a sidereal day until that planet changes direction again. Where is it relative to that bright star? You have just seen retrograde motion!9. Continue to advance by units of one sidereal day until the Sun shows up in the field of view. The date and time of the view is noted along the bottom of the window. What date is it and about how much time has elapsed since you started watching the planetary motions on Feb 21?10. Use the left or right arrow to move your view so you are facing due North. What prominent star is visible nearest the center of your view as you look in this direction?11. Center that prominent star from question 10 using the up/down, left/right arrow keys and then hit the ‘L’ key 3 times. This speeds up the passage of time in the program. Describe what the stars appear to do. If they move in a certain direction, what direction is that? What does the star noted in part 10 above appear to do? What is the obviously special location visible in this view called? HINT: The name of the star you centered the field on will help answer that last question! Press the ‘K’ key to resume the passage of time to its normal rate.12. Open the Location window and search for ‘Melbourne, Australia’ and select that location when it shows up in the listing. Close the Location window. You should still be looking due North. Use the arrow keys to change your view so you are looking due South. As you did in part 11 above, advance the rate at which time passes by pressing ‘L’ 3 times. Describe the motions of the stars you see in this speeded-up view. How does this view differ from what you saw from Ann Arbor when looking North? What prominent location in the sky is clearly apparent in your current view? When done, press the ‘K’ key to resume normal time.13. As a final test of your new Stellarium skills, set the time to your birthday at around noon and set the location to where you were born. Note both that date and that location in the space below. Now, use the arrow keys to find and center the Sun in your field of view. Press ‘B’ then ‘V ‘to show the boundaries and names of the constellations. If the sky is bright, you should also press ‘A’. In which constellation is the Sun located? Is that the constellation of your Zodiac sign? Often it isn’t. BONUS: Can you discover online what effect could have caused the Sun to move to a different constellation than the one corresponding to your Zodiac sign? ................
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