1) Describe the motions of the moon relative to the Earth and the sun. Explain how this causes us to see phases of the moon, and identify these phases by name.

Explanation:

The moon is a natural satellite of the earth, which performs rotational and revolutionary motions simultaneously. As the earth rotates about its axis, the moon rotates round it. But revolves round the Sun, as the earth also revolves round the Sun.

The motion of the moon causes series of its phases. Some major phases of the moon are, new moon, 1st quarter, full moon, and 3rd quarter (last quarter).

Since the moon reflects the light from the Sun, the face of the moon reflecting the light from the Sun changes gradually with respect to its motion.

At new moon, the face of the moon reflect no light. But reflects 100% at full moon. While both 1st and 3rd quarters show partial reflections.