Name: ______Date: ______

SciencePeriod ______

Unit 6 – Astronomy

Lesson 1 – Earth’s Motion

Temperature and Latitude

  1. As earth orbits the Sun, only one half of Earth faces the sun at a time.
  2. A beam of sunlight carries energy.
  3. The more sunlight an area receives the warmer that part of Earth becomes.
  4. Earth is curved, so different parts of Earth’s surface receive different amounts of Sun’s energy.

Energy received by a Tilted Surface

  1. The light energy on a surface becomes more spread out as the surface becomes more tilted relative to the light beam.

The Tilt of Earth’s Curved Surface

  1. Earth’s surface becomes more tilted as you move away from the equator.
  2. A beam of light tends to be more spread out the farther you travel from the equator.
  3. This means regions NEAR the poles receive less energy than regions NEAR the equator.
  4. This makes Earth colder at the poles and warmer at the equator.

Seasons

  1. Seasonal changes DO NOT depend on the Earth’s distance from the Sun. It is the tilt of the Earth’s rotation axis, combined with Earth’s motion around the Sun that causes the seasons to change.

Spring and SUMMER in the Northern Hemisphere

  1. Happens when the northernend of the rotation axis is towards the Sun. The northern hemisphere receives more energy from the Sun than the southern hemisphere.
  2. Temperatures will increase in the northern hemisphere and decrease in the southern hemisphere.
  3. Daylight hours will last longer in the northern hemisphere and nights will last longer in the southern hemisphere.
  4. SO when spring and summer happen in the northern hemisphere, fall and winter will happen in the southernhemisphere.

Draw below how the Earth’s axis is tilted during the SUMMER in the northern hemisphere:

Fall and WINTER in the Northern Hemisphere

  1. Happens when the north end of the rotation axis is away from the Sun.
  2. The northern hemisphere will receive less solar energy.
  3. Temperatures will decrease in the northern hemisphere and increase in the southern hemisphere
  4. This is when Fall and Winter happen in the northern hemisphere; and spring and summer happen in the southern hemisphere.

Draw below how the Earth’s axis is tilted during the WINTER in the northern hemisphere:

HOMEWORK

  1. Why is the Earth warmer at the equator and colder at the poles? (Remember to include facts from above!)

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  1. Choose ONE season either Summer or Winter and DESCRIBE THE SEASON IN THE NORTHERN HEMISPHERE.
  2. What is the position of the rotation axis? (towards or away from the sun?)

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  1. How much solar power is this part of the world receiving?

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c. What is the temperature like?

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  1. What is happening the LENGTH of day and night?

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