Why does the moon have holes (craters)?
The short answer first, then the real reason — and a version for younger kids. Guess before you scroll to make it stick.
✅ Space rocks smashed into it and left dents
But why?
The moon has no atmosphere to burn up incoming rocks and no rain, wind, or plate tectonics to erase scars. Early in the solar system, impacts were frequent, so the surface saturated with craters — the dark ‘seas’ are ancient lava floods that smoothed some regions. Earth got hit just as much, but water, weather, and geology continually resurface it — that’s why our planet looks young and the moon looks ancient.
🧒 For younger kids: Rocks from space SMASHED into the moon and left dents — and with no wind or rain, dents stay forever!
🤯 Wow fact: The moon has no weather — astronaut footprints from 1969 are still crisp and may last millions of years.
Good guesses kids make
“Volcanoes made the holes” — Old idea! Volcanoes shaped a few moon features long ago, but almost all craters are impact dents.
“Because it’s drying out and cracking” — The moon was never wet enough to dry-crack — those circles are collision scars.
“Aliens drilled them” — Fun — but no drill marks. Only rock-on-rock crashes, mapped in detail by orbiters.
More space why questions
- What are shooting stars?
- Why do comets have tails?
- Why does Earth have air but the Moon doesn’t?
- Why is Venus hotter than Mercury, though it’s farther from the Sun?
- Why is the sky blue?