in simple terms does the moon seem to change shape over the month?
The Moon itself does not change shape. If you look at it with a telescope at any point in the lunar cycle you will see that it is all there. What changes is the angle from which the Sun shines on it. The Moon is a sphere which travels once around the Earth every 29 days. As it does so, it is illuminated from varying angles by the Sun. At New Moon, the Moon is between the Earth and Sun, so that the side of the Moon facing towards us receives no direct sunlight, and is only lit by dim sunlight reflected from the Earth. As it moves around the Earth, the side we can see gradually becomes more illuminated by direct sunlight. After a week, the Moon is 90° away from the Sun in the sky and is half illuminated, what we call First Quarter because it is about a quarter of the way around the Earth. A week after this, the Moon is 180° away from the Sun, so that Sun, Earth and Moon form a line. The Moon is fully illuminated by the Sun, so this is called Full Moon. The Earth’s shadow points towards t
