It's not quite accurate to say there's a new phase of the moon *every* night. The phases of the moon are caused by the changing angles of sunlight reflecting off its surface as it orbits Earth.

Here's a breakdown:

* The Moon Doesn't Produce Light: The moon doesn't generate its own light; we see it because sunlight reflects off its surface.

* The Moon's Orbit: The moon orbits the Earth, taking about 29.5 days to complete one cycle.

* Changing Angles: As the moon orbits, the angle at which sunlight hits its surface changes, making different portions of the illuminated side visible to us on Earth.

* The Phases: These changing angles result in the familiar moon phases we see: New Moon, Waxing Crescent, First Quarter, Waxing Gibbous, Full Moon, Waning Gibbous, Last Quarter, Waning Crescent, and back to New Moon.

Why It Seems Like New Phases Every Night: The moon's orbit is not perfectly circular, and the angle of sunlight changes gradually. So, we do see subtle shifts in the illuminated portion of the moon each night, making it appear as if the phases are changing. However, it's actually the same moon, just with a different amount of its surface illuminated by the sun.