Overall, the appearance of the moon phase correlates with the value of the angle between the sun and moon.

Answer 1

Yes, that's correct! The appearance of the moon phase is determined by the relative positions of the sun, moon, and Earth. The value of the angle between the sun and moon changes throughout the lunar month, causing the visible portion of the moon to appear differently from Earth. This is what gives rise to the different phases of the moon, such as new moon, crescent moon, half moon, gibbous moon, and full moon.