Education and
Public Engagement
at the Lunar and Planetary Institute
Explore! Marvel Moon

Rocks Tell Us the Moon's Story



What's the Point?


For the group:

For the facilitator:


A Word on Words . . .

The term "soil" is being used in this activity because children are familiar with "soil." "Regolith" is a more appropriate term and is explored in the activity The Scoop on Moon Dirt.
Soil: the unconsolidated (loose) top layer of material on Earth's surface that is made of minerals and, usually, organic matter in which plants grow.
Regolith: a general term for the layer of loose rock material that forms the surface of a planet — including Earth! — and covers the rock. Soil is a type of regolith. Other types of regolith include volcanic ash, materials deposited by a glacier or river, sand dunes, the red rocky surface materials of Mars, and the layer of material on the lunar surface. 

Dirt: a term often used to describe soil.


1. Show the Lunar Sample Disk to the children and explain that these rocks and "soil" are actual samples that were brought back from the Moon by Apollo astronauts! Describe the technological effort and national pride involved in sending those astronauts to the Moon. Tell the children that the samples are very valuable, so they were set in acrylic so that they could travel around the country, visiting schools and libraries.

Clarify that they might have heard of radiometric dating using the element carbon-14 (carbon dating), but carbon is only one of the elements scientists can use to determine the age of a substance. Carbon dating is useful for determining the ages of relatively young materials — up to about 50,000 years old. Other elements must be used to date older materials, including Moon rocks.

2. Use Snapshots of Distant Time to guide your conversation with the children and relate the samples to the station activities they explored in Growing Up Moon. Discuss each sample, explaining how it was formed and asking the children questions about it.

Add that breccias and soils have been forming throughout the Moon’s history, and they will continue to form through ongoing impacts.

3. As you discuss each sample, invite the children to touch an Earth rock or soil of the same type. Have them use magnifying glasses and their hands, noses, and eyes to note their features.

3. Show the children the images of Earth's oldest rocks as well as the oldest lunar rocks.

Add that lunar rocks record not only the Moon's tumultuous past, but Earth's early and turbulent history. Since there no 4.5-billion-year-old Earth rocks have ever been found to show us that history, we can learn about those impacts from the Moon.


The Moon rocks are treasures to scientists and patriots! Tell the children that scientists are continuing to investigate the lunar samples using new techniques and tools.

If they haven't already done so, invite the children to explore the processes that created each kind of lunar sample through the Growing Up Moon stations and through the night-viewing activity Moon in Action.