What is the Moon's ground covered with?

Have you ever run your fingers through soft sand? It slips and tickles as it falls. Now picture the round, bright Moon high in the night sky.

From far away, the Moon looks smooth, like a silver plate. But astronauts have walked on it, step by step. So what is the Moon's ground covered with?

A thick gray layer lies over the whole Moon. It is moon dust, which means a fine gray powder covering the Moon's ground. It looks as fine as flour.

Let's look closer at moon dust. Every speck of it is rock, in teeny tiny bits. Each bit is smaller than a grain of sand.

On Earth, wind and water rub sand grains until they turn smooth and round. The Moon has no wind and no water. So every bit of moon dust stays sharp and pointy.

This sharp moon dust lies deep, deeper than you are tall. But dust is not the only thing on the ground. If you dug your hands in, what else do you think you would find?

You would find rocks! Small pebbles and bigger stones lie all through the moon dust. Some are boulders, which means rocks bigger than you.

Some boulders are as big as a house. No wind or rain ever rolls them away. So the boulders rest right where they are, sitting in the gray dust.

Moon dust, made of tiny sharp bits of rock, covers the Moon's ground. Big boulders rest in that dust.

High in the night sky, the bright Moon glows. Across its ground, the gray moon dust lies thick and fine. Here and there, a big boulder sits in the dust, resting right where it is.