A Walk Through the Phases
The Moon cycles through its phases every 29.5 days. It starts out looking like a thin crescent in the sky. Over the next two weeks, its appearance slowly changes to a luminous Full Moon that lights up the night. The Moon takes another two weeks to shrink back to a crescent before disappearing briefly during New Moon. A few days later, it shows up again as a crescent. This recurring cycle of phases is the basis for our month.
The Far Side of the Moon
We always see the same side of the Moon. The far side was hidden from our view until astronaut photographs and spacecraft images gave us our first look at this lunar wilderness. Those views revealed a more rugged and cratered surface than the face of the Moon we see. Although the far side is sometimes incorrectly referred to as the “dark side of the Moon,” it receives just as much sunlight as the side facing Earth.