# Solar System on a Stick

Briefing

On a pad and paper, draw a quick sketch of the Solar System. Show where you think the nine different planets are.

Were they spaced out evenly? Were they all the same size? You'll see how the planets shake out in this Smart Art.

Ready? Go to the activity now!

Activity

WHAT YOU'LL NEED:

Construction paper
Posterboard, newspaper, or rolled brown paper
Scissors
Tape
A yardstick

WHAT TO DO:

PART ONE

First, we'll compare how far the planets are from the Sun. Make nine planets out of construction paper. The planets are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto. Don't worry about making the sizes accurate, but they should all be pretty small ? maybe a couple of inches across.

Next, cut nine pieces of string of different lengths. Tape each piece to the center of one of the planets.

Next, tie the strings for each planet to the yardstick at the following spots:

Mercury: 1/3 inch
Venus: 1/2 inch
Earth: 1 inch
Mars: 1 1/2 inches
Jupiter: 4 3/4 inches
Saturn: 8 1/2 inches
Uranus:18 inches
Neptune: 27 inches
Pluto: 36 inches

Now hold the yardstick straight out, so the planets hang down from their strings. In this model, the Sun is at 0 inches (where your hand is). Give your model to another kid so you can see it.

What do you notice about the way the planets are spaced out?

PART TWO

Now, we'll compare how big the planets are. You'll need some big posterboard, newspaper, or rolled paper for some of these. Make new models of the planets. Each planet should be the following distance across the center (for some planets, you'll have to tape pieces together):

Mercury: 2 inches
Venus: 5 1/3 inches
Earth: 5 1/2 inches
Mars: 3 inches
Jupiter: 63 inches
Saturn: 53 inches
Uranus: 22 1/2 inches
Neptune: 21 3/4 inches
Pluto: 1 inch

Label the planets as you make them. What do you notice?

Compare them to the planets hanging from your yardstick. Why do you think you made these models separately?

Debriefing

Why do you think you made two separate models? What do you think the differences between them were? How can they both be correct in their own ways? (Hint: Think about the difference between a city map and a map of the whole country.)

If you've got your Case Journals, answer the questions in it now!