Year 7 Science · Unit 4 · Lesson 17
Master Worksheet
Learning Goals
Read the data table
The table shows the number of known moons for some of the planets. Read it carefully, then answer the questions below.
| Planet | Type of planet | Approximate number of known moons |
|---|---|---|
| Mercury | Rocky inner planet | 0 |
| Venus | Rocky inner planet | 0 |
| Earth | Rocky inner planet | 1 |
| Mars | Rocky inner planet | 2 |
| Jupiter | Gas giant | Around 95 |
| Saturn | Gas giant | Around 145 |
(a) Describe the pattern in the table. How does the number of moons of the rocky inner planets compare with the number for the gas giants?
Compare and justify
Scenario
A student writes: "Moons, asteroids and comets are basically all the same thing, just rocks floating in space." This is a common mistake. Your job is to use what you have learned to show how these three kinds of body are actually different, and where each one is found.
(a) Complete the comparison table. Write one short fact in each empty box.
| Body | What it is made of or how it behaves | Where it is usually found |
|---|---|---|
| Moon | ||
| Asteroid | ||
| Comet |
(b) Explain why the student's statement is not correct. Use at least two clear differences between moons, asteroids and comets to support your answer.
(c) Scientists are very interested in studying asteroids and bringing back tiny samples, such as the grains from asteroid Itokawa that landed at Woomera in South Australia. Justify why studying these ancient rocky leftovers can tell us about how the Solar System formed.
Wrap Up
In one sentence, what was the main idea of this lesson?