1. Standards IE d,,k Students will recognize the usefulness and limitations of models and theories. Students will formulate explanations using logic and evidence Objective 1Describe 2 lines of evidence for Earth’s rotation Objective 2Explain how constellations show evidence for Earth’s rotation Objective 3Explain Earth’s seasons AssessmentChapter Test ReviewDaily Bellwork, Science Starters, Standards Practice Chapter 26, Section 2

2. Vocabulary Create flashcards and study the following words: – Rotation – Revolution – Perihelion – Aphelion – Equinox – Solstice

3. The Rotating Earth The spinning of the Earth on its Axis is called ROTATION. Rotation creates Day and Night Evidence of Rotation— – Foucault Pendulum – Coriolis Effect – Day and Night

4. The Revolving Earth Earth spins on its axis (rotation) and it also travels or REVOLVES around the sun Complete revolution of the sun takes 365 ¼ days. Every four years we add a day…leap year Perihelion=point in orbit closest to the sun Aphelion =point in orbit farthest from the sun

5. Evidence of Earth’s Motion Evidence of Rotation If you watch the night sky over a couple of hours, the stars and constellation patterns appear to move in the sky The moon and sun also appear to change places in the sky Evidence of Revolution Over several weeks a constellations place in the sky will appear to change and at different times of year, different constellations will be visible. See pictures page 669

6. Measuring Time Earth’s motion is the basis for measuring time One day is 24 hours—the amount of time it takes Earth to rotate (spin on its axis) One year is 365 ¼ days –the amount of time it takes to travel (revolve) around the sun

7. Calendar Ancient civilizations: – Egyptians first to use a solar year – Aztecs used a stone calendar to know when to plant – Julius Caesar began leap year Modern Calendar: – 1500s, Pope Gregory XIII created a calendar to fit the seasons

8. Measuring Time Time Zones—24 1 hour periods

9. Seasons Fall and Spring begin on an EQUINOX Winter and Summer begin on a SOLSTICE Brain Pop—Seasons and Solstice and Equinox

10. Interactive/Assessment Constellation Project!

11. INTERACTIVE/Assessment Use the diagram on page 562 or the one below and copy and label it in your notes.