How Astronomers Know — Evidence Lab
Crater Counter
- Estimated time
- ~10 min
Saved locally on this device
Learning goals
- Surfaces with more craters are usually older, because craters build up over time when nothing erases them.
- 5-ESS1-2 — Students analyze daily patterns in shadow, day/night and sky.
Help & glossary
- Use the hint ladder before checking your answer — hints get more specific.
- Incorrect answers can be retried. Feedback explains why.
- Constructed responses (CER) are self-checked — nothing is sent to a server.
Question 1 of 2
Region A has 24 craters. Region B has 4 craters. Which region is likely older?
Craters form when meteoroids hit the surface. On the Moon there is almost no wind or water, so craters stay put for billions of years.
Sources
- Impact Craters — NASA Moon — NASA · NASA Science · Accessed 2026-09-01