7th Grade Chapter 2 Section 1 notes

Here are the notes for Wednesday 8/11.

Mr. Clark

Our Planet, Earth
Chapter 2
Section 1
Earth and Sun
• Orbit- A path one body makes as it circles another
• Revolution- Circular motion
• Axis- an imaginary line running north and south through Earth
• Rotation- each complete turn on its axis
• The earth is tilted 23.5 degrees on its axis.
• The time it takes earth to rotate on its axis is 24 hours
• When it is day in the Eastern hemisphere it is night in the Western hemisphere
• It takes the earth 365 ¼ days to make a revolution around the Sun
Time Zones
• The day starts at a different time all over the Earth
• Time Zones were created to solve this problem
• There is a new time zone every 15 degrees longitude
• One hour between each time zone
Revolution of the Earth
• The earth tilts on its axis a total of 47 degrees per year
• When the N.H. is tilted towards the sun, Summer occurs
• When the N.H. is tilted away from the Sun, Winter occurs
• In between the 2 extremes, Fall and Spring occur
• The Earth is in a constant state of tilting, it is never in one place
• The closer to the Sun the less extremes between the season (Equatorial Region)
• The further from the Sun the more extreme the seasons (Middle Latitude Regions)
• Tropic of Cancer and Tropic of Capricorn represent the tops of the Equatorial Region
• June 21st represents the First day of Summer
• March 21st represents the first day of Spring
• December 21st represents the first day of Winter
• September 23rd represents the first day of Fall
• Solstice- The Sun’s intensity is fully in the Tropic of Cancer or Tropic of Capricorn or Middle Latitude Region
• Equinox- The Sun’s intensity is fully in the Equatorial Region
• Winter and Summer are Solstices
• Fall and Spring are Equinoxes