Why do we see different phases of the Moon?
A) The illuminated half of the Moon becomes more or less visible from Earth as the Moon orbits Earth.
B) The Moon's distance from Earth changes as it moves in its elliptical orbit, thereby changing its apparent brightness.
C) Earth's shadow gradually moves over the Moon's surface as the Moon orbits Earth.
D) The Moon's rotation brings more or less of the illuminated hemisphere into view from Earth.

Question

Quizplus · Accepted Answer

The phases of the Moon are caused by the changing angles of illumination by the Sun as the Moon orbits Earth, making different portions of the illuminated half visible from Earth.

Why Do We See Different Phases of the Moon