Motions of the Planets: Rotation, Revolution, Gravity, Inertia BY: BRIANNA SHIELDS
DO NOW 1. Which planet exhibits retrograde rotation? 2. Which type of “space debris” consists of a ball of ice, snow and dust? 3. Which planet has soil containing iron oxide, a component of rust?
GOAL To be able to describe the bodies found in our solar system and the way in which they move
Gravity and Inertia Gravity Holds planets in orbit around sun, prevents them from flying off
Gravity and Inertia Inertia Allows them to continue in forward motion An object in motion stays in motion, an object at rest stays at rest, unless acted on by a force
Gravity and Inertia WEBSITES Exploring Gravity Keeping Satellites in Orbit Science Monster Gravity and Inertia Game
Rotation versus Revolution Spinning on its axis Causes day and night 24 hours Side facing sun = day REVOLUTION Going around another object Causes seasons 365 1/4 days Hemisphere tilted toward sun has summer
What causes day & night on Earth?
Rotation
Rotation
What causes seasons on Earth?
Seasons Summer Solstice Summer= June 21 (longest day of year) N. hemisphere tilted farthest toward sun N. hemi gets more direct sunlight causing intense warming of earth’s surface
Seasons Winter Solstice Winter= Dec 21 (shortest day of year) N. hemisphere tilted farthest away sun N. hemi gets more spreading of sunlight causing weak rays to hit earth’s surface
Seasons Autumnal Equinox Fall= Sept 21 Earth’s axis is not tilted toward or away from sun After summer, before winter
Seasons Vernal Equinox Spring= March 21 Earth’s axis is not tilted toward or away from sun After winter, before summer
Seasons WEBSITES How does the earth’s tilt cause seasons?
Seasons WEBSITES Seasons Observing Motions in the Sky 1 Orbit Simulator Current Day and Night on Earth
Sketching the Rotation of the Earth Create a sketch of the Earth in your notebook, but make sure you do the following: 1. Draw the sun in the center 2. Draw four Earths in four positions around the sun (summer, winter, spring and fall) 3. Make sure the Earth is tilted correctly for each season 4. Label each Earth with the season and write an explanation as to the cause of each of the seasons
Assessment: Poster Pick your favorite planet and create a poster with the following requirements: Explain each of the following terms by drawing a picture. Accompany each term with a brief explanation. Gravity Inertia Rotation Revolution Now color the planet and record the following for your planet: Amount of gravity Period of rotation Period of revolution
Assessment: Questions Answer each of the following questions in your notebook: 1. How much of the Earth is facing the sun at any given time? 2. How do you know what side of the Earth is experiencing day? 3. When does summer occur in the southern hemisphere (what month). What is going on with the Earth to cause this? 4. What is the name of the Earth’s motion that describes why we have night and day? 5. Explain the positioning of the Earth during the winter solstice
Assessment: Questions Answer each of the following questions in your notebook: 6. What occurs during both the autumnal and vernal equinoxes? 7. Why does the Northern Hemisphere experience winter during November - February? Why is it colder during these months? 8. How long does day last on June 21 in the arctic circle? 9. Where on Earth does the length of day and night never change?