Phases of the moon
Phases of the Moon Study Guide
The moon goes through a series of phases each month as it orbits the Earth. Here are the main phases of the moon:
New Moon:
The moon is positioned between the Earth and the sun, making it invisible from Earth.
Waxing Crescent:
A small sliver of the moon begins to show, gradually increasing in visibility.
First Quarter:
Half of the moon is illuminated. The right side is lit in the northern hemisphere.
Waxing Gibbous:
More than half of the moon is illuminated as it approaches a full moon.
Full Moon:
The entire face of the moon is illuminated, making it fully visible.
Waning Gibbous:
The illumination starts to decrease from the full moon.
Last Quarter:
Similar to the first quarter, but the left side is now illuminated.
Waning Crescent:
A small sliver remains visible as the moon approaches the new phase.
Additional Information:
The cycle from one new moon to the next takes approximately 29.5 days (synodic month).
The moon’s phases are caused by the changing angles of sunlight on the moon as viewed from Earth.