



HOMEWORK ASSIGNMENTS
UNLESS OTHERWISE INDICATED, HOMEWORK ASSIGNMENT ARE DUE AT 11:59 PM ON THE DUE DATE.
Note: To view the homework PDF files, you will need the Adobe Acrobat Reader,
available from http://www.adobe.com.
 Homework #0 (Due 8/28/23, 11:59 pm)
This is a “warmup” homework, to check your mathematical and logic skills.
Homeworks are to be turned in on paper in class.
Also, give this a try (no credit, just bragging rights): A Message to Extraterrestrials
 Homework #1 (due 9/6/23, 6:00 pm)
 Homework #2 (due 9/12/23, 6:00 pm)
 Homework #3 (due 10/2/23, 6:00 pm)
 Homework #4 (due 11/1/23, 6:00 pm)
 Homework #5 (due 12/4/23, at 6:00 pm) This homework is optional, and will count as extra credit if you wish to do it.
 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 Jupiter is where you predicted it would be.
For a more precise check, visit the NASA Jet Propulsion Laboratory HORIZONS System
 Make sure the Target Body is “Jupiter”
 Change the Observer Location to “Washington (USNO) DC”
 Change the Time Span to include Nov. 30, 2023, 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 “2023Nov30 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.
 You can expect to be off by a couple of degrees or so.
 Your azimuth answers will differ by 180 degrees from JPL's answers, since JPL measures azimuth clockwise from North, and our algorithm measures
azimuth clockwise from South. (Unfortunately, there's no universally agreedupon convention for azimuth angles.)
 Hint: Jupiter will be in the constellation Aries.
Contact Information
Dr. David G. Simpson:

