c The Moon does not make its own light; it reflects the light from the Sun
The Sun continuously illuminates half of the Moon’s surface, but varying amounts of it are visible from Earth at any moment
Changes in visibility of the Moon’s surface follow a predictable pattern called the lunar cycle
The positions of the Sun, Earth, and Moon as they move through space cause the lunar phases to occur to viewers from Earth
The Moon revolves around the Earth about every 28 days
he lunar phases change about every 3.5 days