one of the aspects of the moon as we see it from Earth, relating to how much of it is visible at different times of the months.
One of the aspects of the moon as we see it from Earth is its changing phases, which determine how much of the moon's illuminated side is visible to us at different times of the month. These phases are primarily due to the positions of the moon, Earth, and the sun in relation to each other.
The moon orbits around the Earth, and as it does so, we see different portions of its illuminated surface depending on where it is in its orbit. The moon's phases are categorized into eight distinct stages:
1. New Moon: In this phase, the moon is positioned between the Earth and the sun, with its dark side facing us. As a result, the moon appears completely dark and is not visible during this phase.
2. Waxing Crescent: As the moon moves slightly away from the sun, a small crescent-shaped portion of its illuminated side becomes visible. The lit area gradually increases over the following days.
3. First Quarter: While half of the moon's illuminated side is visible during this phase, it appears as a half-moon shape. The term "first quarter" refers to the fact that the moon has completed approximately one quarter of its lunar cycle.
4. Waxing Gibbous: Following the first quarter, the moon continues to wax, meaning its illuminated portion grows larger. In this phase, more than half of the moon is visible, but it is not yet a full moon.
5. Full Moon: When the moon is positioned opposite the sun, its entire illuminated surface is facing us. Thus, a full moon appears as a complete, round disk in the sky. Full moons occur roughly every 29.5 days.
6. Waning Gibbous: After the full moon, the moon begins to wane, meaning its illuminated portion starts to decrease. During this phase, more than half of the moon is still visible, but it is not a full moon anymore.
7. Third Quarter: The third quarter phase occurs when the moon has completed approximately three-quarters of its lunar cycle. In this phase, exactly half of the moon's illuminated side is visible, but it appears as a half-moon shape opposite to the first quarter phase.
8. Waning Crescent: As the moon approaches its new moon phase, only a thin crescent-shaped portion of the illuminated side is visible. The lit area continues to decrease until it becomes completely dark again, marking the start of a new lunar cycle.
The moon's changing phases are a result of its position relative to the sun and Earth. As it orbits the Earth, sunlight falls on different areas of its surface, leading to the varying visibility of its illuminated side.