Solar System Mass Distribution

This demonstration uses 10 potatoes as a model to show how mass is distributed in the solar system. Almost all of the solar system’s mass is contained in the sun, while Jupiter, Saturn, Uranus, and Neptune account for most of the remaining fraction, with the smaller planets, moons, and other objects contributing very little.

1. Place 10 potatoes in a basket to represent the total mass of the solar system.
2. Calculate the relative mass of the sun (99.85%), and cut off part of one potato to represent the rest of the solar system.
3. Further divide this part to represent the masses of the largest planets (use https://en.wikipedia.org/wiki/List_of_Solar_System_objects_by_size to help with calculations).

📄 List of Solar System objects by size - Wikipedia: https://en.wikipedia.org/wiki/List_of_Solar_System_objects_by_size

• Use apples, beads, or other classroom-friendly objects instead of potatoes.
• Compare with a pie chart or bar graph of solar system mass distribution.
• Have students build their own mass distribution models with food or objects.

• Use caution when cutting potatoes; knives should be handled by an adult or under supervision.
• If food is used, avoid waste by cooking or composting afterward.

• What percentage of the solar system’s mass is in the sun? (About 99.8%.)
• Why do Jupiter and Saturn account for most of the remaining mass? (They are gas giants made mostly of hydrogen and helium, which makes them very massive.)
• How does Earth’s mass compare to Jupiter’s? (Jupiter is about 318 times more massive than Earth.)
• Why do smaller bodies like asteroids and moons contribute so little to the solar system’s mass? (Because they are tiny compared to the planets and the sun, even though there are many of them.)