1. TOPIC #1: Chapter 22 Origin of Modern Astronomy

2. Section 2: The Earth, Moon, Sun System Earth has two forms of motion: Rotation, which is the turning of an object on an axis. Revolution, which is the motion of a planet or moon along its orbit.

3. Section 2: The Earth, Moon, Sun System The Earth rotates on a tilted axis. (This gives us the seasons.) It takes the Earth about 24 hours to make one rotation.

4. Section 2: The Earth, Moon, Sun System The Earth makes one orbital revolution in about 365 days. When the earth is farthest from the sun it is at its apihelion About July 4 each year. When the earth is closest to the sun it is at its perihelion About January 3 each year.

5. Section 2: The Earth, Moon, Sun System The direction of the tilt of Earths axis determines the seasons.

6. Section 2: The Earth, Moon, Sun System The moon rotates around the earth in a similar way to the earth rotating around the sun. When the moon is closest to the earth it is at perigee. When the moon is farthest from the earth it is at apogee.

7. Section 2: The Earth, Moon, Sun System Due to this rotation we witness phases of the moon on a monthly basis.

8. Section 2: The Earth, Moon, Sun System A waxing moon is when the moon appears to be growing in visibility. A wanning moon is when the moon appears to be shrinking in visibility A crescent moon is a moon that is less than half visible. A gibbous moon is a moon that is more than half visible

9. Section 2: The Earth, Moon, Sun System During the full moon and new moon phases the moon must pass in line with the earth and the sun. At the correct angle Solar and Lunar eclipses may occur. Solar Eclipse, when the moon moves directly between the earth and the sun blocking the sun from view. Lunar Eclipse, when the earth moves directly between the moon and the sun shadowing the moon from the suns light.