Below is a model of the Earth-Sun-Moon system to describe the cyclic patterns of lunar phases as viewed from Earth.
The Earth-Sun-Moon system is a dynamic celestial dance influencing lunar phases. In this model, the Earth orbits the Sun, and the Moon orbits the Earth. The Sun, a radiant energy source, illuminates the Moon's surface, causing varied lunar phases.
From Earth, we observe these phases as the Moon's position relative to the Sun changes during its orbit. New Moon occurs when the Moon aligns with the Sun, casting the dark side toward us. Waxing and waning crescents and gibbous phases follow as we witness different illuminated portions.