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Chapter 7 Homework

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Scholars Online Astronomy - Chapter 7: Basic Planetology


Reading Preparation

Reading: Astronomy, Chapter 7: Our Solar System

Study Notes: notes on your assigned reading from the text

We move now from methods of observing and basic physics of orbital motion to examining the physical bodies in the solar system: the planets, their moons and rings, stray bits called asteroids, occasional visitors called comets. The sun we treat as a special case of a star. In chapter 7, we have an overview and look at the current theories proposed for the formation of the solar system.

Key Formulae to Know

  • Average Density: ρ average   =   m total V total
  • Kinetic energy and temperature E K   =   ½ m v 2   =   3 2 kT
  • Average speed of gas atom or molecule v   =   3 kT m
  • Escape velocity v   =   2 GM R

Web Lecture

Read the following weblecture before chat: The Solar System

Study Activity


Use your planetarium program to view magnified images of the terrestrial planets (Mercury, Venus, Earth, Mars), and the asteroid Ceres from different positions in space. Alternatively, The Nine Planets website has an interactive solar system model. It takes awhile to load so be patient.

  • Which planets have clouds?
  • Which planet or asteroid shows the heaviest cratering?
  • Which of these planets show evidence of liquid water?

Now use your planetarium program to look at the Jovian planets (Jupiter, Saturn, Uranus, and Neptune).

  • Which planet has the greatest color contrast in its cloud tops?
  • Which has the least color contrast?
  • What can you say about the thickness of the rings of each planet compared to the diameter of the planet?

UNL Tools Exercises

  • Interactives:
    • Under Miscellaneous, rank planet densities.
  • ClassAction:
    • Under Solar System Objects, concentrate on planetary densities (5-7), orbit characteristics and planetary types (8-10, 15), classification of planets (14)
  • NAAP Labs:
    • Review Kepler's Laws and Newton's laws, then use the Planetary Orbits simulator to explore the modern theory of orbits (ellipses).

Optional Websites: Bill Arnett is a software engineer by profession. Early on in the adventure of the web, he started putting together The Nine Planets site, where collected lots of information about the planets. This is a good starting place for almost everything named in the solar system: the planets, their moons, major comets and asteroids, and exploration. I usually don't recommend sponsored sites (this one is sponsored by Google Ads) because I can't count on the information or presentation being appropriate in all cases for students, but I've never seen anything offensive here (annoying yes -- ads are inherently so); still, visit this at your own risk.

Chat Preparation Activities

Chapter Quiz

Lab Work

Read through the lab for this week; bring questions to chat on any aspect of the lab, whether you intend not perform it or not. If you decide to perform the lab, be sure to submit your report by the posted due date.