Grade: Grade 5 Subject: Science Unit: Solar System SAT: ProblemSolving+DataAnalysis ACT: Science

Investigation Lab: Scale Model Solar System

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Lab Investigation

Build a scale model to understand the vast distances between planets in our solar system!

Research Question

How can we use a scale model to understand the relative distances between planets in our solar system?

Background Information

Space is enormous! The distances between planets are so vast that they're hard to imagine. Scientists use a unit called an Astronomical Unit (AU) to measure distances in space. One AU equals the distance from Earth to the Sun - about 150 million kilometers (93 million miles)!

In this investigation, you'll create a scale model - a smaller representation where all distances are reduced by the same factor. We'll use 1 meter = 1 AU, making our model something you can actually walk through!

What is Scale? When we say our scale is "1 meter = 1 AU," we mean every 1 meter in our model represents 150 million kilometers in real life. This is a ratio of 1:150,000,000,000!

Planet Distances from the Sun

Planet Distance from Sun (AU) Model Distance (meters) Model Distance (steps*)
Sun 0 0 m Start here!
Mercury 0.4 AU 0.4 m ~1 step
Venus 0.7 AU 0.7 m ~1 step
Earth 1.0 AU 1.0 m ~2 steps
Mars 1.5 AU 1.5 m ~3 steps
Jupiter 5.2 AU 5.2 m ~10 steps
Saturn 9.5 AU 9.5 m ~19 steps
Uranus 19.2 AU 19.2 m ~38 steps
Neptune 30.0 AU 30.0 m ~60 steps

*One step is approximately 0.5 meters (about 1.5 feet)

Materials Needed

  • Measuring tape or meter stick
  • Chalk or cones/markers
  • Index cards (9)
  • Markers or colored pencils
  • Calculator
  • Data recording sheet
  • Large outdoor space (gym or field)
  • Optional: Different sized balls for planets

Safety Reminders

  • Stay within designated boundaries
  • Be aware of your surroundings when walking
  • Handle measuring equipment carefully
  • Follow all instructions from your teacher

Procedure

  1. Prepare Your Planet Cards

    Create an index card for each planet. Write the planet name, draw a picture, and include the distance from the Sun in AU. You'll place these cards at the correct locations in your model.

  2. Set Up Your Starting Point (The Sun)

    Choose a starting location and place a marker or draw a large circle to represent the Sun. This is position 0 in your model.

  3. Measure and Mark Inner Planets

    Starting from the Sun, use your measuring tape to mark Mercury (0.4 m), Venus (0.7 m), Earth (1.0 m), and Mars (1.5 m). Place each planet card at its location.

  4. Measure and Mark Outer Planets

    Continue measuring to place Jupiter (5.2 m), Saturn (9.5 m), Uranus (19.2 m), and Neptune (30.0 m). Notice how the distances get much larger!

  5. Walk Your Solar System

    Walk from the Sun to each planet in order. Record your observations about the distances. How did it feel walking from Mars to Jupiter compared to walking from Earth to Mars?

  6. Calculate and Compare

    Calculate: How many times farther is Jupiter from the Sun than Earth is? (Hint: Divide Jupiter's distance by Earth's distance: 5.2 / 1.0 = ?)

Record Your Observations

Scientists always record what they observe during investigations. Answer these questions in your science notebook:

  1. What patterns did you notice about the spacing between inner planets versus outer planets?
  2. How did building this model change your understanding of our solar system's size?
  3. If you could add dwarf planet Pluto (at 39.5 AU), where would it be in your model?

Practice

Use what you learned from the investigation to answer these questions.

1 In a scale model where 1 meter = 1 AU, how far from the Sun would you place Jupiter?
A 1.5 meters
B 5.2 meters
C 9.5 meters
D 30 meters
2 What is an Astronomical Unit (AU)?
A The distance from Earth to the Moon
B The distance from Earth to the Sun
C The distance across our Milky Way galaxy
D The distance light travels in one year
3 Saturn is approximately 9.5 AU from the Sun and Earth is 1 AU from the Sun. About how many times farther from the Sun is Saturn than Earth?
A About 5 times farther
B About 8 times farther
C About 9.5 times farther
D About 19 times farther
4 Looking at the data table, which statement best describes the pattern in planetary distances?
A All planets are equally spaced from each other
B Inner planets are closer together; outer planets are much farther apart
C Outer planets are closer together than inner planets
D The distances decrease as you move away from the Sun
5 Why do scientists use scale models?
A To make objects look prettier
B To understand very large or very small things that are hard to visualize
C To save paper when drawing diagrams
D Because real measurements are always wrong
6 If Neptune is at 30 AU and you're using a scale of 1 cm = 1 AU, how far would Neptune be in your model?
A 30 cm
B 30 m
C 3 cm
D 300 cm
7 The distance from Mars (1.5 AU) to Jupiter (5.2 AU) is about how many AU?
A 1.5 AU
B 3.7 AU
C 5.2 AU
D 6.7 AU
8 Which best explains why there is a large gap between Mars and Jupiter in our solar system?
A Scientists made a measuring error
B The asteroid belt occupies the space between Mars and Jupiter
C Mars and Jupiter repel each other
D There is no gap between them

Check Your Understanding

Scale Models

Reduce everything by the same factor to compare relative sizes and distances accurately.

Astronomical Unit

1 AU = distance from Earth to the Sun (about 150 million km).

Inner vs Outer

Inner planets are close together; outer planets are spread far apart.

Making Predictions

Use ratios to calculate distances in different scale models.

Key Takeaways

  • Scale models help us visualize things too large (or small) to see directly
  • The inner planets (Mercury, Venus, Earth, Mars) are relatively close to the Sun and each other
  • The outer planets (Jupiter, Saturn, Uranus, Neptune) are much farther away with greater spacing
  • Neptune is 30 times farther from the Sun than Earth is!

Next Steps

  • Try making a scale model using 1 cm = 1 AU and compare how it differs
  • Research where the dwarf planet Pluto would be in your model (39.5 AU)
  • Explore how long it takes spacecraft to travel to different planets
  • Continue to the Data and Graphs lesson to analyze planetary data