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

Future Moon: The Footsteps of Explorers

Adapted from part B of The Scoop on Moon Dirt, Explore! To the Moon and Beyond – with NASA's LRO Mission, Lunar and Planetary Institute.


Children drop impactors onto layers of graham crackers! The process models how impacts throughout the Moon's history have broken rocks down into a mixture of dust, rocks, and boulders that covers the lunar surface. They consider how the dust will continue to hold a record of human exploration — in the form of astronaut bootprints — for countless years in the future. Children may examine a type of Earth soil ("lunar soil simulant") that is similar to what is found on the Moon’s surface and that would have been shaped by the processes explored here. The children create their own records of exploration by making rubbings of their shoes to decorate the library or take home.

What's the Point?


The following materials are for one The Footsteps of Explorers activity setand will serve approximately 10 children working in teams of two to three.
Two sets are recommended for a station:

For each child:

For the facilitator:

Facilitator's Note: Children may investigate lunar dust and the problems it poses for exploration in the Explore! To the Moon and Beyond! activity, The Scoop on Moon Dirt.



Described in the children's guide.


The children should identify the rock or baking soda box as an asteroid. Just as the graham crackers were crushed over time, the impacts over billions of years have ground the lunar rocks into a fine, brittle dust. Unlike on Earth, the Moon's surface is not broken down by water, wind, and other processes. The footprints of the Apollo astronauts remain preserved in the dust on the lunar surface.

A Little Background for the Facilitator

The Moon is covered with circular patches. Some of these are huge, covering more area than the state of Texas. Some are miniscule, smaller than the tip of a pin. All are caused by the innumerable meteoroids and comets bashing into the surface of the Moon over its 4.5-billion-year lifetime. The large ones you can see from your backyard were created when large meteoroids — asteroids — or comets impacted the Moon. Smaller ones were made by smaller meteoroids. Impactors come in all sizes, and they create circular depressions — craters — of all sizes. These impacts pulverized rocks on the lunar surface, reducing them to a dusty, rock material called regolith that covers the Moon's surface — in some cases deeper than 50 feet (15 meters).

The Moon has no atmosphere, so there is no wind, and there is no flowing water on the Moon to weather away the surface The Apollo astronauts explored six small areas on the Moon and left their footprints preserved in the dust.

Scientists at the Colorado Center for Lunar Dust and Atmospheric Studies are investigating the nature of lunar dust and its impact for human exploration of the Moon. The Lunar Reconnaissance Orbiter (LRO) mission is currently orbiting the Moon and mapping the presence of different elements and characterizing the regolith. The Lunar Atmosphere and Dust Experiment Explorer (LADEE) mission, scheduled to launch in 2011, will collect data about lunar dust while orbiting the Moon.