Welcome to this experimental science test. We hope that you will find it interesting and worthwhile. Carefully read through these directions and the directions on the next page before you begin to work.

You may be part of a group for the first part of this exercise. Each group should carry out the experiment and collect the data together, but each student must record the data in his or her own booklet. Be sure to record the data exactly as you observe them. After the data have been collected, each student should answer the questions independently.

After you have finished your experiment and have recorded all of the data, you will be asked to answer some questions about the experiment and the data you recorded. Your answers must be written in this test booklet in the space provided. Make sure that you understand each question before you begin to write. At any time while you are writing your answers, you may look back at the directions for the experiment and the data you collected. Be sure that your answers are written as clearly and neatly as possible.

Before you turn the page, read the list of materials given below and check to make sure that your group has everything listed.

Materials in the Kit 5 stick-on dots Materials Supplied by the School pen or pencil

Scale Model of Solar System

The National Aeronautics and Space Administration (NASA) is sponsoring a contest for students. The student who creates the best map of the planets in our solar system will get to go to a NASA Space Camp for a week. As a part of the contest, students are asked to make an accurate representation of the relative distances of the planets from each other. The average distances between the Sun and the planets are shown on the chart below, measured in kilometers.

Planet Distance Chart

Planet	Mean distance from Sun (km)
Mercury	5.8 x 107
Venus	10.8 x 107
Earth	15.0 x 107
Mars	22.8 x 107
Jupiter	78.0 x 107
Saturn	143 x 107
Uranus	228 x 107
Neptune	451 x 107
Pluto	592 x 107

1. Look at Figure 1 on page 5. You will notice that the Sun is placed in the upper right corner of the page. Determine where Earth, Mars, Jupiter, Saturn, and Pluto should be placed. Put a stick-on dot at the appropriate location and label the dot. Be sure to include a legend showing your scale. Your model should be drawn to scale.

Figure 1

2. Suppose you were planning a space flight from Earth to Venus. The distance between the planets is 42,000,000 km. A friend of yours proposes traveling along a straight line between the planets. Explain why a straight line of travel between Venus and Earth is not practical. Be sure to justify your answer.

3.(a) The length of a planet's "year" can be defined as the amount of time, in Earth years, it takes a planet to go once around the Sun. If the average speed of a planet around the Sun decreases with distance from the Sun, which planet has the longest year and which planet has the shortest year? (Note: You do not have to specify the length of the planet's year.) Be sure to justify your answer.

3. (b) Which planet has a "year" that is closest in length to Earth's year? Explain your answer.