Science Focus Lesson SC.4.E.5.4 Rotation Polk County Public Schools

SC.4.E.5.4 Benchmark: Relate that the rotation of Earth (day and night) and apparent movements of the Sun, Moon, and stars are connected. Essential Question: How does the movement of the Earth affect what we see in the sky? Vocabulary: rotationaxis revolutionmoon phases

Earth’s Rotation Rotation is a movement similar to a spinning top Rotations are PREDICTABLE and REGULAR The Earth rotates on its axis once every 24 hours The Earth’s axis is an imaginary line that passes through Earth’s center from the North Pole to the South Pole

Apparent Movement Earth rotates from west to east on its axis. This makes the sun, moon and stars look as though they are moving from east to west. We say that the sun, moon, and stars rise in the east and set in the west. However…it is actually the Earth’s rotation that causes this apparent movement. Click on Earth for a link

Day and Night Earth rotates on its axis once every 24 hours. As the Earth spins on its axis, we are carried in and out of the sunlight that is always shining on half the planet. This is why we have day and night once every 24 hours. Click on this link

Summarizing Collaborative Pairs: Partner A: Tell partner B one result of the Earth’s rotation Partner B: Tell partner A another result of the Earth’s rotation

Earth’s Revolution A revolution is a complete trip around the sun One revolution equals a year The Earth makes one revolution in 365 days The path of a revolution is called an orbit, it’s shape is an ellipse (like a flattened circle) Click for link

The Night Sky Because of the Earth’s revolution we see different star patterns in different seasons Because of the Earth’s revolution we have four seasons

Moon’s Movement The Moon’s movements are similar to Earth’s movements The Moon rotates (spins) as it revolves around the Earth The moon’s rotation and revolution both take about 28 days The shape of the moon appears to be different as a result of the Moon’s movements which change the part of the moon that reflects light from the Sun to Earth. These are called Moon Phases

Summarizing Collaborative Pairs: Partner A: Tell partner B one result of the Earth’s revolution around the Sun Partner B: Tell partner A another result of the Earth’s revolution around the Sun

Guided Instruction: Talk to your shoulder partner about the answer to each question. Check your work. Children all over the earth experience night and day. At the same moment, it can be morning in America and nighttime in China. What causes day and night? A The tilt of the earth on its axis B The rotation of earth on its axis C The phases of the moon D The Sun revolving around the earth

The answer is The rotation of earth on its axis causes day and night. One rotation of Earth equals one day. At any time, half of Earth faces the sun. That half has daytime. At the same time, the other half of Earth faces away from the sun. That half has nighttime.

Guided Instruction: Which of these is a result of the spinning of Earth on its axis? A.The apparent motion of the Sun in the sky B.The motion caused by Earth’s revolution C.The length of a year D.The change from spring to summer

The answer is The apparent motion of the Sun in the sky is caused by the Earth’s rotation from west to east on its axis. This makes the sun look as if it were rising in the east and setting in the west.

Guided Instruction: How long does Earth take to rotate once? A.365 hours B.24 hours C.12 hours D.365 days

The answer is Earth rotates on its axis once every 24 hours. One rotation of Earth equals one day.

Summarizing Stand and Share:  In 30 sec. groups write answers to the essential question  Compile all of the answers on the board Essential Question: How does the movement of the Earth affect what we see in the sky?

Check Your Understanding What causes the phase of the Moon to change each night during a 28 day period? A. The Moon changes its actual shape throughout the course of the month. B. The alignment between the Earth, Moon, and Sun determines the amount of light reflected by the Moon. C. The season of the year determines the phase of the Moon. D. The closer the Moon is to Earth, the more light the Moon reflects.

Check Your Understanding Keisha wants to show Amy what happens during one Earth day. Keisha holds a small globe representing Earth, and Amy holds a large ball representing the Sun. What should Keisha do to show Amy what happens during one Earth day? A. Keisha should move the globe in one complete circle around Amy. B. Keisha should move the globe toward Amy and then away from her. C. Keisha should slowly lift the globe above her head and then lower it. D. Keisha should slowly spin the globe one complete time about its axis.

Check Your Understanding Charles learned that Earth rotates on its axis. What evidence supports the theory that Earth is rotating on its axis? A. There is a day and a night. B. There are 365 days in each year. C. There are four phases of the Moon. D. There are different seasons of the year.

Check Your Understanding What evidence is there that the Earth is revolving around the Sun? A. There is day and night B. The sun appears to rise in the east and set in the west C. The moon cycles through its phases every 28 days D. Different stars are visible in the night sky during different seasons

Check Your Answers 1. B 2. D 3. A 4. D

In your science journal, write an answer to the essential question: How does the movement of the Earth affect what we see in the sky? Summary Question