The Moon’s Cycle Objective: Students will be able to identify and classify the phases of the moon, the related orbit times and its relationship to seasons by analyzing and summarizing text by the end of the lesson.

The Moon’s Cycle Essential Question: What are the phases of the moon?

The Moon’s Cycle

The Moon When you look up at the night sky, you may see the moon. It sometimes appears like a large, bright circle, full of light. In fact the moon has no light of its own. The moon is illuminated because it reflects the light from the sun. The part of the moon facing the sun is lit up. The part facing away from the sun is in darkness.

The Moon’s Revolution The revolution of the Moon around the Earth makes the Moon appear as if it is changing shape in the sky. From Earth we see the Moon grow from a thin crescent to a full disk (or full moon) and then shrink back to a thin crescent again before vanishing for a few days.

Moon Phases The phases of the Moon depend on its position in relation to the Sun and Earth. As the Moon revolves or orbits (makes its way around) the Earth, we see the bright parts of the Moon's surface at different angles. These are called "phases" of the Moon. The moon has eight (8) phases.

The New Moon The first phase of the moon is called the New Moon. To the naked eye it appears as if there is no moon at all. This is because the shadow cast by the sun completely obscures (blocks out or covers up) the view of the moon. If the sun is east of Earth, then the new moon will be on the right in the 3 o’clock position. This moon will last 3.5 days, then the next phase begins.

Waxing Crescent Moon The second phase of the moon is called the Waxing Crescent Moon. To the naked eye it looks like a giant, white thumb nail on the right. This is because the shadow cast by the sun obscures about 90% of the moon’s surface. The word ‘waxing’ means ‘getting larger’ and the word ‘crescent ‘ is the name given to the thumb nail shape. If the sun is east of Earth, then the waxing crescent moon will be on the right between the 1 and 2 o’clock positions. This moon will last 3.5 days, then the next phase begins.

First-Quarter Moon The third phase of the moon is called the First-Quarter Moon. To the naked eye it looks like a giant, black and white cookie with the right side being vanilla. This is because the shadow cast by the sun obscures about 50% of the moon’s surface. If the sun is east of Earth, then the first-quarter moon will be at the top at the 12 o’clock position. This moon will last 3.5 days, then the next phase begins.

Waxing Gibbous Moon The forth phase of the moon is called the Waxing Gibbous Moon. To the naked eye it looks like a black thumbnail has been cut from the left side of the moon. This is because the shadow cast by the sun obscures more than 50% of the moon’s surface. The word ‘gibbous’ is the name given to the moon shape that is more than half but less than full. If the sun is east of Earth, then the waxing gibbous moon will be on the left between the 10 and 11 o’clock positions. This moon will last 3.5 days, then the next phase begins.

Full Moon The fifth phase of the moon is called the Full Moon. To the naked eye it looks like a giant, bright circle. This is because the shadow cast by the sun does not obscures any of the moon’s surface. The full moon always rises and sets at the same time as the sun. If the sun is east of Earth, then the full moon will be on the left at the 9 o’clock position. This moon will last 3.5 days, then the next phase begins.

Waning Gibbous Moon The sixth phase of the moon is called the Waning Gibbous Moon. To the naked eye it looks like a black thumbnail has been cut from the right side of the moon. This is because the shadow cast by the sun obscures more than 50% of the moon’s surface. The word ‘waning’ means ‘getting smaller’. If the sun is east of Earth, then the waning gibbous moon will be on the left between the 7 and 8 o’clock positions. This moon will last 3.5 days, then the next phase begins.

Third-Quarter Moon The seventh phase of the moon is called the Third-Quarter Moon. To the naked eye it looks like a giant black and white cookie with the left side being vanilla. This is because the shadow cast by the sun obscures about 50% of the moon’s surface. If the sun is east of Earth, then the third-quarter moon will be at the bottom at the 6 o’clock position. This moon will last 3.5 days, then the next phase begins.

Waning Crescent Moon The eighth and final phase of the moon is called the Waning Crescent Moon. To the naked eye it looks like a giant, white thumb nail on the left. This is because the shadow cast by the sun obscures about 90% of the moon’s surface. Remember, the word ‘waning’ means ‘getting smaller’, so this ‘crescent ‘ is the getting smaller. If the sun is east of Earth, then the waxing crescent moon will be on the bottom right between the 4 and 5 o’clock positions. This moon will last 3.5 days, then the cycle will start again. The lunar cycle last about 28 days (nearly a month).

Lunar Cycle