Name: _______________________________________________ Date: ___________________ Bell #: __________________ Unit 2 Solar System Study Guide Part I: Define the following terms. You may use your note cards, notes, or book to find the correct answers. 1. Orbit: Earth’s curved path that it follows around the sun 2. Rotation: Planet spinning on an axis; takes the Earth 24 hours or 1 day to complete one rotation 3. Revolution: Earth’s yearly orbit around the sun; about 365 days to complete once 4. Axis: imaginary vertical line that passes through Earth’s center creates a North and South pole 5. Winter season: a cold season with shorter daylight hours 6. Summer season: a hotter season with longer daylight hours 7. Maria: a large dark spot or area on the moon 8. Crater: round or bowl-like pits that are found on the moon’s surface 9. Umbra: the darker part of the shadow during an eclipse 10. Penumbra: the lighter part of the shadow during an eclipse 11. Comet: chunks of ice and dust particles; orbits are very long 12. Meteoroid: a piece of rock and dust particles (similar to the materials from the planets) 13. Asteroid: rocks that revolve around the sun 14. Asteroid belt: large collection of asteroids located between the orbits of Mars and Jupiter Part II: Answer the following questions using complete sentences. You may use your notes, quizzes and book to find the answers. 1. Describe Aristotle’s model of the universe. Believed that the Earth was the center of the solar system; universe was perfectly circular 2. Describe Copernicus’s model of the universe. Believed that the sun was the center of the solar system; first to suggest the sun was the center; placed planets in correct order 3. Describe Ptolemy’s model of the universe. Believed that the Earth was the center of the solar system like Aristotle; Earth was slightly off to one side; order of the planets – Mercury, Venus, Sun, Mars, Jupiter and Saturn 4. Describe Galileo’s model of the universe. Believed the sun was the center of the solar system; used the telescope to discover Venus went through phases, saw craters and marias. Found that Jupiter had four moons. 5. Explain the third and most common theory of the origin of the moon. The earth ejected molten material that formed into the moon. 6. Explain the moon’s rotation and revolution. The moon takes 27.3 days to rotate on its axis and 27.3 days to revolve around the earth. 7. Give 3 facts about Mercury. Closest planet to the sun; greatest range of climate/temperature in the solar system; and made up of dense material. 8. Give 3 facts about Venus. Reterrograde rotation – rotates backwards; called the morning and evening star – because it is sometimes the brightest object in sky; called Earth’s twin because it is similar in size. 9. Give 3 facts about Earth. Only planet that has water in the form of a solid, liquid and gas; only planet to support life; and has three main layers 10. Give 3 facts about Mars. Reddish in color because of the rust on its surface; 1% of earth’s pressure; people thought there were canals on its surface 11. Give 3 facts about Jupiter. Has a very thick atmosphere; great red spot = storm larger than earth; largest planet in the solar system 12. Give 3 facts about Saturn. Second largest planet in the solar system; has several rings; and it’s atmosphere is mostly hydrogen and helium 13. Give 3 facts about Uranus. Rotates on its side; a gas giant; and has five large moons with icy craters 14. Give 3 facts about Neptune. Atmosphere contains visible clouds; has storm activity like Jupiter – on dark spots; and 30 times farther from the sun than the earth 15. Give 3 facts about Pluto. A dwarf planet; smallest planet; and has one moon 16. How are the inner planets different from the outer planets? The outer planets are gas giants and the inner planets are mostly solids; inner planets are closer to the sun than the outer planets; and the inner planets are hotter than the outer planets. 17. How are the inner planets similar to the outer planets? They all follow an elliptical orbit around the sun; all in the same solar system and they are all planets Part III: Illustrate the following using your book, notes, or quizzes. 1. Solar eclipse: label the sun, moon, earth, penumbra and umbra. 2. Lunar eclipse: label the sun, moon, earth, penumbra and umbra. 3. Label the parts of a comet. 4. A meteoroid getting closer to the Earth. 5. 8 moon phases and write a brief description for each.