Why Does the Moon Change Shape?

The Moon is always round, but from Earth we see different parts of its sunlit half. As the Moon travels around Earth, the angle between the Sun, Earth, and Moon changes. That is why we see a new moon, crescent moon, half moon, and full moon during one lunar cycle.

A good observation activity is to keep a moon journal for four weeks. Look at the Moon at roughly the same time each evening, draw its shape, and write one sentence about where you saw it in the sky.

This activity builds scientific observation, pattern recognition, and patient data collection, which are important habits for young researchers.