What is the origin of 'sleep tight'? One of the mysteries of the English language finally explained.
The moon doesn't glow in a very real sense. It reflects the Sun's light. (Or the Earth's light if you're not on Earth and in the right position.) As Quora User says, the moon has a high albedo. So it reflects pretty well.
Moonlight is sunlight bouncing off the Moon's surface. As the Moon orbits Earth, the Sun lights up whatever side of the Moon is facing it. To the Sun, it's always a full Moon! If you were looking down upon Earth and its Moon from way out in space over the North Pole, you would see a Moon that looked like one of these: