Lunar Phases and Eclipses

• The moon revolves around the Earth once every 27 days.

• Only ½ of the moon is lit by the sun.

• The different phases that we see result from our seeing the Moon from different angles.

Reasons for the Phases

Names of the Phases• The phases in chronological order

1. New Moon

2. Waxing Crescent

3. First Quarter

4. Waxing Gibbous

5. Full Moon

6. Waning Gibbous

7. Third Quarter

8. Waning Crescent• The term ‘waxing’ means

growing. • The term ‘waning’ means

shrinking.

The Waxing Cycle of Phases

Waxing Crescent First Quarter Waxing Gibbous Full Moon

The Waning Cycle of Phases

Waning Gibbous Third Quarter Waning Crescent New

Rotation: Spinning on an axis of rotation. (Creates day and night.)

Revolution: Movement of a body around something else.(Creates a year or a lunar cycle.)

Solar Eclipse

• The moon casts a shadow on the Earth.• Occurs during new moon phase• Inclination model

Lunar Eclipse• The Earth casts a shadow on the moon.• Occurs during full moon phase.

Anatomy of a Shadow• Penumbra

– Region of partial shadow

– Partial eclipse will be seen

• Umbra– Region of total shadow– Total eclipse will be

seen.

Umbra

Penumbra

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Lunar eclipse information