1. Earth in Space
Section 1-1 P

2. Astronomy The study of space.
The study of the Moon stars and other objects in Space.

3. Movement of Earth and Planets
Rotation: When an object spins on its axis (like a top)
1 rotation = 1 day
Earth 1 day = 24 hours

4. Revolution The movement of one object around another.
Orbit = path around the Sun
1 revolution = 1 year
Earth 1 year = 365 ¼ days

5. Calendars
Ancient Egyptians created one the first Calendars. They had about 365 days in a Year.
The Month is based on the Moon Cycle. 29 ½ days.
Romans had a Calendar with 365 ¼ Days
365 ¼ days? - Leap Year

6. Seasons The Earth has seasons because its axis is tilted 23 ½ degrees.
How the sunlight hits the Earth determines the seasons.
Direct rays = summer Indirect rays = Winter

7. Solstice Winter: The shortest day of the Year (about Dec. 21)
Summer: The longest day of the Year
(about June 21)

8. Equinox Equal day and night
Autumn: Autumnal Equinox - First day of Fall
(about Sept. 21)
Vernal: Spring Equinox – First day of Spring
(about March 21)