* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Seasons and the Tilted Earth Name TEK 8.7A Date Period _____
Survey
Document related concepts
Formation and evolution of the Solar System wikipedia , lookup
History of Solar System formation and evolution hypotheses wikipedia , lookup
Extraterrestrial life wikipedia , lookup
Copernican heliocentrism wikipedia , lookup
Rare Earth hypothesis wikipedia , lookup
Tropical year wikipedia , lookup
Astronomy on Mars wikipedia , lookup
Extraterrestrial skies wikipedia , lookup
Astronomical unit wikipedia , lookup
Comparative planetary science wikipedia , lookup
Hebrew astronomy wikipedia , lookup
Geocentric model wikipedia , lookup
Dialogue Concerning the Two Chief World Systems wikipedia , lookup
Transcript
Seasons and the Tilted Earth TEK 8.7A Name ____________________________ Date __________________ Period _____ Most places on Earth experience four seasons every year. These are spring, summer, fall and winter. The seasons are caused by a combination of things: The Earth being tilted as it moves around the sun. Direct sunlight producing more heat than indirect light. The Earth moving around the sun in a non-circular way. This is how it works. Remember that the Earth is tilted all the time that it is moving around the Sun. The Earth moves around the Sun once every year. It follows an elliptical orbit. This means that it goes almost in a circle around the sun, but gets a little further away at some times. The path it takes is like an oval. When the Northern hemisphere is pointing at the sun, sunlight falls most directly on it. This is summer in the Northern Hemisphere because direct light causes more heat than indirect. As the Earth moves around to the other side of the Sun the Northern Hemisphere is tilted away from the Sun. Now the light falls indirectly on it. It is winter. When the Northern Hemisphere has summer, the Southern Hemisphere has winter, and the other way round. The Earth's axis is tilted 23.45°. This tilting is what gives us the four seasons of the year: Summer, spring, winter and fall. Since the axis is tilted, different parts of the globe are pointed towards the Sun at different times of the year. Summer is warmer than winter (in each hemisphere) because the Sun's rays hit the Earth at a more direct angle during summer than during winter and also because the days are much longer than the nights during the summer. During the winter, the Sun's rays hit the Earth at an extreme angle, and the days are very short. These effects are due to the tilt of the Earth's axis. Adapted by KA Baker, Godley Middle School, 2012, from M. Poarch – 2001 http://science-class.net Now you think the teacher is daft, because it seems like she has said the same thing many times. I have and I hope you get it. Before you begin lab: 1. What is the shape of the Earth’s orbit? ___________________________________ 2. Does the Earth’s distance from the sun change very much during the year? _________ 3. If the Earth did move closer or farther from the Sun, would it be colder or hotter everywhere on Earth at the same time? ________ What evidence did you use to support your answer?_________________________________________________________ Materials: Styrofoam Earth model light source Procedure: 1. Label the color of the dots below to match the earth model. Spin Axis 2. Hold your model with the spin axis in a vertical position. Slowly spin counterclockwise the model and watch the dots go from daylight to night and back to daylight. When the spin axis is vertical, do the dots stay in the light the same amount of time during rotation? _______________________ 3. Is this how the Sun-Earth system really works? Why or why not? _______________ __________________________________________________________________ __________________________________________________________________ Adapted by KA Baker, Godley Middle School, 2012, from M. Poarch – 2001 http://science-class.net 4. Tilt the Earth toward the sun, roughly halfway down. Spin the Earth model again and observe the dots. Compare what is happening at the red dot (mid-latitude North) and the black dot (mid-latitude South). ___________________________________________ __________________________________________________________________ __________________________________________________________________ 5. What is happening to the blue dot? ______________________________________ __________________________________________________________________ __________________________________________________________________ 6. What is happening at the South Pole? ____________________________________ __________________________________________________________________ __________________________________________________________________ 7. Compare what is happening in the two Northern cities. _______________________ __________________________________________________________________ __________________________________________________________________ 8. What season is it on the red dot? _______________________________________ 9. What season is it on the blue dot? ______________________________________ 10. How are they different? ____________________________________________ __________________________________________________________________ 11. All of the Northern hemispheres in our models are tilted toward the Sun, and have summer. Is this how it really is? _____________Explain _______________________ __________________________________________________________________ __________________________________________________________________ Adapted by KA Baker, Godley Middle School, 2012, from M. Poarch – 2001 http://science-class.net 12. How does the season change from summer to fall to winter to spring and back to summer during the year?________________________________________________ _________________________________________________________________ _________________________________________________________________ _________________________________________________________________ 13. As the Earth moves around the Sun, the North Pole always points toward the North Star. Point your model toward the “North Star.” North Star 14. Label each hemisphere with the appropriate season. Adapted by KA Baker, Godley Middle School, 2012, from M. Poarch – 2001 http://science-class.net