Homework Assignment #1

Name:

Section number:

Date Due: Sept. 15

1. If you were standing on the earth's equator, where would you look to see the north celestial pole? Could you see this pole from Australia? Why/why not?

2. Where would you look in the sky to find the ecliptic/zodiac? What object(s) would be useful as guides?

3. Describe the changing position of the rising sun on the eastern horizon throughout a year, with special emphasis on the solstices and equinoxes.

4. Sketch the retrograde motion of a superior planet (e.g., Mars) relative to background stars. Label the east and west directions clearly on your diagram.

5. The Sun is roughly 400 times the diameter of the Moon. Yet, the Sun and Moon have the same apparent angular diameter (0.5 degree), as seen from Earth. How is this possible?

6. The moon circuits the zodiac in about 27 days (a sidereal month). What is its average angular speed per day? Why does the sidereal period differ from the moon's cycle of phases (a synodic month), which is 29.5 days?