1. Notes 15 – The Seasons Mrs. Gordon Earth Science Saturday, March 05, 2016Saturday, March 05, 2016Saturday, March 05, 2016Saturday, March 05, 2016

2. 1. The Basics A. Earth’s Rotation = 1 DAY or 24 hoursA. Earth’s Rotation = 1 DAY or 24 hours B. Earth’s Revolution = 1 YEAR or 365.25 daysB. Earth’s Revolution = 1 YEAR or 365.25 days

3. 2. Sunrise / Sunset A. The Sun ‘rises’ in the….. –E–E–E–EAST B. The Sun ‘sets’ in the….. –W–W–W–WEST C. But the Sun does not really rise and set because…….. We live in a HELIOCENTRIC system (Sun-centered). D. This apparent motion of the Sun is due to Earth rotating on its axis.

4. 3. Why does Earth have seasons? A. Earth has seasons because the planet has a TILT to it axis (23.5°)A. Earth has seasons because the planet has a TILT to it axis (23.5°) –Because of this TILT the NH & SH of our planet receive different amounts of solar energy as we revolve around the Sun.

5. 4. Special days of the Year Note: All of the following are referencing the Northern Hemisphere. ~ Vernal Equinox – March 21 st, 12 hours of day / 12 hours of night (sunlight hits the equator directly)~ Vernal Equinox – March 21 st, 12 hours of day / 12 hours of night (sunlight hits the equator directly) ~ Summer Solstice ~ June 21 st, longest day / shortest night (most direct sunlight of the year)~ Summer Solstice ~ June 21 st, longest day / shortest night (most direct sunlight of the year) THEN DAYS GET SHORTER THEN DAYS GET SHORTER ~ Autumnal Equinox – September 21 st, 12 hours of day / 12 hours of night (sunlight hits the equator directly)~ Autumnal Equinox – September 21 st, 12 hours of day / 12 hours of night (sunlight hits the equator directly) ~ Winter Solstice – December 21 st, shortest day / longest night (most indirect sunlight of the year)~ Winter Solstice – December 21 st, shortest day / longest night (most indirect sunlight of the year) THEN DAYS GET LONGER THEN DAYS GET LONGER

6. Add the seasons diagram to your notebook: Shade in the nighttime side of Earth.Shade in the nighttime side of Earth. Label SUN.Label SUN. Label PolarisLabel Polaris Label the following positions/dates for the Northern Hemisphere:Label the following positions/dates for the Northern Hemisphere: June 21 - Summer solsticeJune 21 - Summer solstice September 21 - Autumnal equinoxSeptember 21 - Autumnal equinox December 21 - Winter solsticeDecember 21 - Winter solstice March 21 - Vernal equinoxMarch 21 - Vernal equinox