63. A TRIP TO THE PLANETS

SUBJECT: Science
GRADE: 7,8,9
GROUP SIZE: Small
TIME: Several periods
TYPE OF ACTIVITY: Student Investigation
TEACHING STRATEGY: Open Discovery Guided Discovery
CONCEPTS: Solar System Planet Environment
SKILLS: Reading for Information Presenting Data
Objectives: To provide students with an understanding of some of the similarities and differences between the planets; to provide an understanding of the environmental conditions of the planets.

Jupiter image

Materials: Books, pamphlets, etc., on the various planets; discussion sheet.
Teacher Background Information:

The ancient astronomers observed points of light in the sky which appeared to wander among the stars. They called these objects planets, which means “wanderers,” and named them after great mythological deities – Jupiter, king of the Roman gods; Mars, the Roman god of war; Mercury, messenger of the gods; Venus, the Roman god of love and beauty; and Saturn, father of Jupiter and god of agriculture.

In the past 25 years of the Space Age, knowledge about the solar system has advanced farther than in all the previous centuries since civilization began. Revolutionary views of the planets have been provided, mostly by NASA spacecraft but also by NASA-supported telescopic, balloon, sounding rockets and high altitude aircraft studies.

Mercury has been seen by Mariner 10 spacecraft and sharp pictures of about half of the planet’s surface have been provided. The Pioneer Venus mission dropped five probes into the Venusian atmosphere and put an orbiter around the planet. Earth has been viewed from space in a number of ways including weather satellites, Landsat and, of course, by our astronauts standing on the Moon. Viking spacecraft have brought information of Mars and raised as many questions as they have answered.

These are exciting times for astronomers and your students can begin a look at this solar system of ours at a time when news is abundant and ever changing.
Procedure:

1. Write the word PLANET on the chalkboard and ask what the word means. Arrive at a workable and accurate definition and write it on the board.
2. Ask what the planets of our solar system are called. Write them on the board.
3. Ask what solar system means. Clarify its meaning with students and write it on the board.
4. Have the students put the planets in relative order from the Sun. As the class discusses the planets in the solar system, work through the definitions of at least these words before they proceed: planet, star, solar system, galaxy and universe. Write any questions that come up during the discussion on the chalkboard and let students know they will be finding information on some of these questions.
5. Divide the class into groups and assign them a specific planet. They are to search for information on the environmental conditions of their planets.

They should look for such things as:

• the atmosphere of the planet
• any rocks or minerals the planet contains
• any forms of life
• the range of temperatures
• how the planet might have originated
• when astronomers first found it
• its distance from the Sun and from the Earth
• how the planet compares to other planets, especially to the Earth
• any moons or rings it may have
• what spacecraft or techniques were used to gather data about the planet

Once the data is gathered, each group is responsible for providing a detailed booklet complete with pictures or diagrams for the other groups to read. This is a big responsibility so information must be accurate and up-to-date. Make sure your students know that this writing is to be read and will be accepted as factually and honestly presented.

After the class has had the opportunity to read all the booklets, hold a general class discussion and discuss some of the questions on the activity sheet found on the following page.
Extension:

Have students write a travelogue script from the point of view of the planets; that is, in the first-person, i.e., “I am Mercury. I … etc.) Select photos of the various planets from the NASA web site, find music appropriate for a planetary travelogue and put together a presentation for other classes to see and hear.

Jupiter looms ahead of the Voyager 1 spacecraft. The Great Pied Spot is visible at the lower left. Slightly above the feature, and to the right, is the volcanically active moon Io.
A TRIP TO THE PLANETS

Questions for Discussion

1. What are some of the similarities between the inner planets?
2. What are some of the differences?
3. Why do ground telescope observers have difficulty in studying Mercury?
4. Why is life on Mercury impossible?
5. Describe Venus’ cloud cover and atmosphere.
6. Describe the planetary theory regarding a planet’s loss of the original gases in its atmosphere.
7. Which of the four inner planets apparently has no magnetic field?
8. What do you think would happen to Earth if all of the carbon dioxide locked up in its rocks suddenly escaped into its atmosphere? What could cause this cataclysm?
9. There are three hypotheses on how the inner planets acquired potentially volatile materials: primary atmosphere, grain accretion, and external source. Describe them and explain why you think a particular one is most likely.
10. Why are conditions on Earth favorable to life?
11. Why has Earth’s atmosphere caused the premature fall of the Skylab space station?
12. Give and explain your theory of the Moon‘s origin?
13. Discuss why you think or don’t believe that there is or was life on Mars?
14. Why do geologists enjoy studying Mars?
15. Why does the Mars moon Phobos interest scientists?
16. How does the nature of the solar system change beyond Mars?
17. How many satellites has Saturn?
18. What are the most popular hypotheses concerning the origin of Saturn’s rings?
19. How does Saturn resemble Jupiter? Uranus? Neptune?
20. What is the solar system’s largest satellite? It’s smallest? It’s most (environmentally) like the Earth? It’s most likely to have resources the Earth can recover and use?