1. Earth-Moon-Sun System
Chapter 22 Section 2

2. Draw and label all the Phases of the moon.
Daily Objective
Draw and label all the Phases of the moon.

3. Key Questions What perihelion and aphelion?
What is perigee and apogee?
What is the difference between a solar and lunar eclipse?

4. The sun, Earth, and Moon share a special relationship to our perspective.
As the largest celestial bodies in our skies, they’re responsible for many of the solar phenomena we experience.
The way we experience these events depends largely on their individual motions of these bodies and their relative positions in the cosmos.

5. Earth’s Motions Earth has three principle motions: Rotation Revolution
Precession

6. Earth’s Motions
Rotation is responsible for the day and night cycle of Earth.
There are two different types of days.
Mean Solar Day
Sidereal Day

7. Earth’s Motions
The mean solar day is 24 hours long and marks the time it takes for a location to travel from 12am noon to 12am noon.
The sidereal day is 23 hours and 56 minutes and marks the time it takes for the light of a distant star to hit the same location on Earth.

8. Earth’s Motions
Revolution is the motion of Earth around its orbit of the Sun.
At certain points in Earth’s orbit it will be either closer or further away from the sun.
Perihelion – Closest to the sun
Aphelion – Furthest from the sun
Think Pair Share
How might Kepler’s laws of planetary motion apply here?

9. Earth’s Motions

10. Earth’s Motions Precession is the slowest of Earth’s movements.
Precession is the wobble of Earth’s axial tilt.
This has little effect on Earth’s seasons.

11. Earth Moon Relationship
Just like the Earth’s orbit around the Sun, the Moon orbits in an ellipse.
Perigee – Closest to Earth
Apogee – Furthest from Earth

12. Earth Moon Relationship
The position of the moon in relation to the Earth and Sun is responsible for the phases of the moon.
Reflected sunlight is responsible for the moon’s glow.

13. The moon’s bright side is shown to earth when it is on the other side of the Earth.
The moon’s shadow side faces Earth when it lies between the Sun and Earth.

14. Earth Moon Relationship
The synodic month is based on the cycle of the moon’s phases. It lasts 29 1/2 days.
There are two types of Lunar Months.
Synodic Month
Sidereal Month
The sidereal month is the true period of the moon’s revolution around Earth. It lasts 27 1/3 days.

15. Eclipses
The Earth, Sun, and Moon share one last relationship – eclipses.
There are two types of eclipses.
An eclipse occurs when one celestial object moves into the shadow of another.

16. Solar Eclipse
Solar eclipses occur when the moon moves in a line directly between Earth and the sun, casting a shadow on Earth.

17. Lunar Eclipse
Lunar eclipses occur when the moon passes through Earth’s shadow.

18. END