Prince George's Community College

Fall 2019

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UNLESS OTHERWISE INDICATED, HOMEWORK ASSIGNMENT ARE DUE AT 11:59 PM ON THE DUE DATE. If you wish, you may hand in your homework in class on the day before the due date.

Note: To view the homework PDF files, you will need the Adobe Acrobat Reader, available from

  • Homework #1 (due 9/5/19, 11:59 pm)
  • Homework #2 (due 9/12/19, 11:59 pm)
  • Homework #3 (due 9/19/19, 11:59 pm)
  • Homework #4 (due 10/17/19, 11:59 pm)
  • Homework #5 (due 10/31/19, 11:59 pm)
  • Homework #6 (due 12/4/19, IN CLASS at 6:00 pm)
    • Now includes the correct epoch time for Uranus, T0 = JD 2458800.5
    • You are required to do parts (a)-(m). You may do parts (n)-(p) for extra credit.
    • You may find the Julian day using either NASA tables or the NASA JPL Web site. There is also a simple computer program for computing the Julian day here.
    • If you wish to check your final answer, go outside around dusk and see if Uranus is where you predicted it would be. (You'll need a telescope!) For a more precise check, visit the NASA Jet Propulsion Laboratory HORIZONS System
      • Change the Target Body to “Uranus”
      • Change the Observer Location to “Washington (USNO) DC”
      • Change the Time Span to include Dec. 5, 2019, and set the calculation interval to 10 minutes.
      • Under Table Settings, change “angle format” to “decimal degrees”
      • Click the “Generate Ephemeris” button. Look for the line that reads “2019-Dec-05 01:00” and check the R.A. and DEC. against your right ascension and declination. They won't match exactly, since JPL's calculation is more precise than yours, but it should be close.
    • Hint: Uranus is currently in the constellation Aries.
    • The Flight of Friendship 7

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    Dr. David G. Simpson:

Webmaster: Dr. David G. Simpson
Page last updated: November 27, 2019.