1. Earth-Sun Relationship

2. Solar System
Consists of the sun and 8 planets
Most planets have moons

3. Solar System
Gravity from the Sun keeps the planets in the solar system
Gravity from the planets keep their moons orbiting the planets
One complete cycle around any celestial body is called a “revolution”

4. Seasons are caused by a combination of the tilt of the earth’s axis and it’s position around the sun

5. revolution and tilt

6. The Tropics and the Arctic Circles
The Tropics are the area where the sun is directly overhead at some point in the year
The Arctic and Antarctic Circles mark the area where the sun is either above or below the horizon for at least 24 hours.
At least 24 hours of night or 24 hours of daylight

7. Solstices
Solstices happen in winter and summer when the sun’s most direct rays strike either the
Tropic of Cancer –summer solstice (longest Day)
Tropic of Capricorn-winter solstice (shortest day)

8. Equinox
When the sun is directly on the Equator the earth has an Equinox
When you have 12 hours of day (daylight) and 12 hours of night (darkness)
Autumnal Equinox – Sept. 22 or 23
Vernal Equinox – March 21 or 22

9. VIDEO!!