Know the phases of the Moon

The Moon is the satellite of the Earth that we can see in the night sky. The Moon is about a quarter (27%) the size of Earth and is a dusty, rocky place. Other planets also have their own moons or satellites.

The phases of the Moon occur for two reasons: the Moon orbiting around the Earth and because the Moon reflects light from the Sun like a mirror.

The Moon is illuminated by the Sun as it orbits (rotates) the Earth, which means that sometimes people can see the entire Moon and other times only small parts of it. This is because the Moon does not emit its own light like the Sun. What we see of the Moon are the parts that are being illuminated by sunlight. These different stages are known as phases of the Moon.

New Moon: occurs when the Moon passes between the Earth and the Sun. In this phase we cannot see it because the unlit part of the Moon faces the Earth.

First quarter: we see half of the moon. This phase gets its name because over the days the illuminated portion of the Moon grows in size.

Full Moon: The half of the Moon facing the Earth is illuminated and we see the full Moon.

Last quarter: we see the half of the Moon that was not visible in the first quarter. It is called waning because with the passing of days its light decreases.

The Moon takes about 29.5 days (29 days, 12 hours, 44 minutes) to orbit the Earth. The complete cycle, called a lunation, occurs when the Moon goes from large and bright to small and dark and back to large and bright.

Did you know . . . ?

✔ Eclipses occur when the Sun, Earth, and Moon are in perfect alignment. A solar eclipse occurs when the Moon passes in front of the Sun, and can only occur on a new moon. A lunar eclipse occurs when the Moon passes through the Earth’s shadow, it can only occur on a full moon.
✔ The first calendars were created based on the lunar cycle.
✔ Gravity on the Moon is one-sixth of the gravity on our planet, which means something will be six times lighter on the Moon than it is on Earth.