Every month Earth's moon goes through its phases, waning and waxing in its constant transformation from new moon to full moon and back again.

This lunar cycle happens in part because the moon does not produce its own light; the silvery glow we see comes from sunlight reflecting off the moon's monochrome surface. In addition, our view of the moon is governed by a gravitational quirk called tidal locking. In essence, it takes roughly the same amount of time for the moon to spin once on its axis as it takes for our celestial companion to complete an orbit around Earth. That means the same side of the moon always faces Earth, although both sides get illuminated as the