Space
Why Does the Moon Have Phases? The Science Explained
Half the Moon is always sunlit; phases are how much of that lit half we see as the Moon orbits Earth. The synodic month lasts 29.5 days, moving through new, crescent, quarter, gibbous, and full phases. Phases are NOT Earth's shadow—that's an eclipse. The Moon always shows us the same near side due to tidal locking, a gravitational dance between Earth and Moon.