Why do the moon's phases look like they do?

Answer 1

The moon's phases look the way they do because it takes one monthe for the moon to rotate around the Earth. You can only see certain parts of the moon because the light of the sun shines only on the part of the moon not covered by the Earth.

Answer 2

The moon's phases are the result of its changing position relative to the sun and Earth. As the moon orbits Earth, the amount of sunlight it reflects back to us changes, creating the different phases we see from Earth. These phases include new moon, first quarter, full moon, and last quarter.