Standards IE d,,k Students will recognize the usefulness and limitations of models and theories. Students will formulate explanations using logic and evidence.

Standards IE d,,k Students will recognize the usefulness and limitations of models and theories. Students will formulate explanations using logic and evidence

Objective 1 Describe 2 lines of evidence for Earth’s rotation

Objective 2 Explain how constellations show evidence for Earth’s rotation

Objective 3 Explain Earth’s seasons

Assessment Chapter Test

Review Daily Bellwork, Science Starters, Standards Practice

Chapter 26, Section 2

Vocabulary

• Create flashcards and study the following words:– Rotation– Revolution– Perihelion– Aphelion– Equinox– Solstice

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

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

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

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

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

AztecMayan

ROMAN

Measuring Time

• Time Zones—24 1 hour periods

Seasons

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

Interactive/Assessment

• Constellation Project!

INTERACTIVE/Assessment

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