Solar System Scale Models
Introduction: A scale model is a representation of a real-life object that has been made in exact proportion
to that object. You may have seen a model car or ship that has been made in the exact proportions of a lifesize car or ship, but much smaller. A map is another example of a scale model. Yesterday, we learned that to
make a scale model of the solar system, we need to have REALLY BIG distances. We can’t make a model
of the solar system with the same scale for distance and size within this classroom. Today you will make a
scale DISTANCE model of the planets in the solar system.
Materials:
paper,
colored pencils
meter stick and/or metric ruler
calculator
table of planetary distances
Procedure:
1. Calculate planetary distances from the sun in astronomical units (AU).
Remember, one astronomical unit is equal to the average distance from Earth to the sun, which is
approximately 93 million miles, or 150 million kilometers (km).
Divide each planet’s distance from the sun in km by the number of km in one AU, which is 150 million km.
 Let’s do Mercury together:
distance of Mercury = distance of Mercury from sun in km = 58 million km = 58 = 0.39 AU
from sun in AUs
distance of Earth from sun in km
150 million km 150
 Fill in the rest of Column 4 with the distances from the sun in AUs.
2. SCALE ~ You need to determine the scale you will use for your model.
 If you look in the third column of the table, you will see the scale we used on our solar system
walk yesterday. Every meter in our model was equal to 6,000,000 km in real life. This scale would be too
large for a model that could fit on a piece of paper.
 If we use the scale distance given in the 5th column below, 1 AU will be represented by 10 cm.
That means every 10 centimeters on the scale model represents 1 AU in “real life.” Therefore we would
place the picture of the Earth 10 cm from the drawing of the sun.
3. Multiply each planetary distance in AUs by the scale distance.
 Since Mercury is 0.39 AUs from the sun, we would multiply 0.39 by 10 to find out how many
centimeters on the model are needed to show 0.39 AU. Therefore, at the scale of 1 AU = 10 cm, we would
place our model Mercury at 3.9 cm from our model Sun.
4. Determine the scale distance you will use. Then follow the same steps as above and fill in the last column
of the table.
5. Use a long strip of paper to make your model. Even though we are not making the planets to scale, you
can draw them in the correct place. Use a compass or trace a round object to get nice circles!
Table of Planetary Distances
Planet or
Distance from
Dwarf Planet
Sun (km)
SS Walk
scale distance
Distance from
Sun in AUs
Scale Distance
10 cm = 1 AU
0.39
3.9
1
10
1 m = 6 million km
Mercury
58 million
10
Venus
108 million
18
Earth
150 million
25
Mars
228 million
38
Jupiter
780 million
130
Saturn
1,430 million
238
Uranus
2,890 million
478
Neptune
4,520 million
799
Pluto
5,890 million
983
.
Scale Distance
1 AU = ______ (cm)