Earth Science Chapter 27 Study Guide

Transcription

1 Name: KEY Vocabulary: Match each term with the best description. 1. A solar system 2. C nebula 3. B Planetesimal 4. I Protoplanet 5. Q Exoplanet 6. O Dwarf planet 7. P Asteroid belt 8. F Kuiper belt 9. D Differentiation 10. J Outgassing 11. E Ozone 12. L Axis 13. H Rotation 14. K Orbit 15. M Revolution 16. G Solstice 17. N Equinox a. A star and all the planets and bodies that travel around it b. Small body from which a planet originated in the early solar system c. Rotating cloud of gas and dust from which solar systems form d. Process that solid Earth went through to form the core, mantel, and crust e. Ammonia and water vapor broke down to form this substance which protects Earth from solar radiation f. Region beyond Neptune and has objects made mostly of ice g. When tilt of Earth s axis is directed towards or away from the Sun h. Spin of a body on its axis i. Planetesimals join together through collisions make larger bodies j. Process that formed early Earth s atmosphere from volcanic eruptions k. Path an object takes as it revolves l. Imaginary line that runs from the North to South pole of Earth, tilted at 23.5 m. When an object moves around another object n. When there is 12 hours of sunlight and 12 hours of night time o. Object that orbits the sun, is round, has not cleared its orbital path of debris, and is not a moon p. Region between Mars and Jupiter where most asteroids are q. Planets that circle stars in other solar systems

2 18. Describe the nebular hypothesis. A nebula collapsed due to the force of gravity and started to spin, from the spinning planetesimals, then protoplanets and finally planets formed and orbited around the star. The star formed where the graviy collapsed. 19. How is the original hypothesis of the origin of the solar system different from the nebular hypothesis? Originally thought Sun formed and then materials were thrown off from the Sun and formed the planets. This is different from current nebular hypothesis which says Sun and planets formed at same time. 20. Who hypothesized the nebular hypothesis? Pierre Simon 99% 21. Approximately how much matter of the original nebula would be contained in the star that becomes the center of a solar system? 22. Summarize the steps of solar system formation (6 steps). 1.) Solar nebula begins to collapse because of gravity 2.) Solar nebula rotates, flattens, and becomes warmer in the center 3.) Planetesimals begin to form within the swirling disk 4.) As planetesimals grow, their gravitational pull increases. The largest planetesimals begin to collect more of the gas and dust of the nebula 5.) Small planetesimals collide with larger ones and the planets begin to grow. 6.) the excess dust and gas is gradually removed from the solar nebula, which leaves planets around the sun and thus creates a new solar system

3 23. How is a planetesimal and protoplanet different from each other? Planetesimals are smaller particles colliding to form a larger mass Protoplanets are several planetesimals colliding to form a larger mass 24. State all 8 planets in order from the Sun to exterior of the solar system. Divide them into the inner and outer planets. Inner: Mercury, Venus, Earth, Mars, Outer: Jupiter, Saturn, Uranus, Neptune 25. What do scientists believe happened to the lighter element of the inner planet s atmosphere? Inner planets didn t have a strong enough force of gravity to keep the gases in the atmosphere so: 1.)blown away by solar winds 2.) boiled away by solar radiation 26. Describe two pieces of evidence that there could have been life on Mars at some point. 1.) A lot of frozen water stuck in icecaps 2.) Evidence of water erosion on surface 3.) Found minerals that could only form in liquid water 27. Why is Mars red? The surface rock contains a lot of iron that oxidizes (rusts) and turns red 28. Most water on Mars is in what state of matter? Solid ice 29. Why are the inner planets called inner and the outer planets called outer? Inner because they are inside the asteroid belt and outer because they are outside the asteroid belt 30. What are the second names for the inner and out planets groups, why do they have these second names? Inner= Terrestrial --- name due to being made mostly of solid rock Outer= gas giants --- name due to them being larger in size than inner planets and composed mainly of gas

4 31. Describe the asteroid belt location and what is found there. Located between Mars and Jupiter and is where most asteroids are found and orbit the Sun. 32. Each planet is thought to have a core made of metal. 33. What is a ring system? Where do scientists think the rings came from? Rings of dust and ice debris that s located around each outer planet 34. What is Earth s orbital period and axis rotation? Orbit: 365 ¼ days axis: 24 hours 35. What three features of Earth make it unique and capable of supporting life? Liquid water Stable temperature High amount of oxygen 36. Solid Earth formed three distinct layers of the crust, mantel, and core through a process called differentiation, which separated the planet into layers based on material density. 37. State what the three layers of the core, mantle, and crust are primarily composed of. Core iron and nickle Mantle iron and magnesium Crust silica rich rock 38. Today s interior of Earth is very hot, while the surface of earth is colder. 39. The original atmosphere of Earth had a lot of Hydrogen and Helium, but today s atmosphere does not. State the two possible explanations for this. Inner planets didn t have a strong enough force of gravity to keep the gases in the atmosphere so: 1.)blown away by solar winds 2.) boiled away by solar radiation 40. What process formed the early Earth s atmosphere? Outgassing release of gases from volcanic eruptions

5 41. What gasses were in early Earth s atmosphere? Nitrogen, water vapor, ammonia, methane, argon, sulfur dioxide, carbon dioxide 42. How did ozone form? Ammonia and water vapor broke down from solar radiation and the remaining atoms formed ozone 43. What does ozone do for planet Earth? Forms shield around Earth so not too much ultraviolet radiation hits the surface allowed simple life forms to evolve. stabilized the temperature 44. What were some of the early life forms on Earth? Cyanobacteria and green plants 45. Why were early life forms able to survive? They were autotrophs that didn t require oxygen 46. What process did the early life forms go through and how did it change the atmosphere? Photosynthesis allowed oxygen to enter the atmosphere 47. What is the current composition of Earth s present atmosphere? 78% nitrogen, 21% oxygen, 1% other gases 48. How do scientists think Earth s oceans became salty? Rocks weathered from rainfall, rock minerals entered oceans, chemical reaction formed salts and over time the water became salty 49. Why does Earth have seasons? The Earth s axis is tilted so during its orbit sunlight hits parts of the planet at different angles, creating different temperatures on Earth s surface giving the seasons 50. Describe Earth s rotation and axis. Earth spins on its axis (rotates) giving us daylight and nighttime. Axis is slanted at 23.5 degrees and extends from south to north poles of Earth

6 51. What accounts for the temperature difference in summer versus winter? Summer is when sunlight directly hits a certain location on Earth, Winter is when indirect sunlight (more angled light) hits Earth at a certain location Winter 52. If its summer in the Northern hemisphere what season is it in the Southern hemisphere? 53. How often do solstices and equinoxes occur? Both happen twice a year 54. State the dates of the solstices and equinoxes. Why are they approximate dates? Solstices: Dec. 21 winter June 21 Summer Equinoxes: March 21 spring Sept. 21 fall Approximate dates because orbital period not exactly 365 days. There is a 14 of a day that causes the beginning of the seasons to change slightly from year to year. We try to synchronize the seasons and our calendar by having a leap year. 55. How are solstices and equinoxes different? Solstices are when one hemisphere of Earth is tilted directly toward the Sun and the other directly away. Happens when Earth is farthest from Sun in its orbit. Equinoxes occur when both hemispheres evenly face the Sun so that the equator is in line with the Sun s / solar system celestial equator. This causes Earth to have exactly 12 hours of daylight and 12 hours of darkness 56. What is the current definition of a planet? Object orbits Sun Object is round due to its gravitational force Dominates its neighborhood by clearing it of debris 57. Why is Pluto no longer a planet? It does not dominate its neighborhood/ clear orbit path of debris 58. Why was Pluto a strange planet when it was considered a planet?

7 Had a highly elongated orbit path and it was tilted out of line of the other planets orbit plane Smaller than Earth s moon 59. What does Pluto consist of? Primarily frozen methane, rock and ice 60. Pluto is currently a dwarf planet, what does this mean? a. Orbits the sun. b. Has enough mass to assume a nearly round shape. c. Has not cleared the neighborhood around its orbit. d. Is not a moon. 61. Where do comets usually orbit? KEUPER BELT Identify the following as characteristic of inner or outer planets by placing a I for those that describe inner and O for those that describe the outer planets. 62. Are smaller I 63. Made mostly of rock I 64. Have a lot of moons O 65. Contain lighter elements O 66. Are denser I 67. Are less dense O 68. Have ring systems O 69. Contain a lot of helium and hydrogen O 70. Contain zero to two moons I 71. Are extremely cold due to distance from Sun O 72. Are more massive in size O 73. Made mostly of gas O 74. Have a lot of impact craters I Identify which of the 8 planets the following unique characteristics pertain to. 75. Temperature range between 427 C and -173 C MERCERY 76. Has marsquakes MARS 77. Similar to Earth in size and density VENUS

8 78. Has a runaway greenhouse effect VENUS 79. Surface has a reddish color MARS 80. Atmospheric pressure is 90x that of Earth VENUS 81. Great Red Spot JUPITER 82. Great Dark Spot NEPTUEN 83. Has atmosphere that is 92% hydrogen and helium but not nuclear fusion JUPITER 84. Has rings 2x its diameter SATURN 85. Shortest orbital period MERCURY 86. Longest orbital period NEPTUNE 87. Least dense planet SATURN 88. Largest planet JUPITER 89. Smallest planet MERCURY 90. Has large amount of methane in its atmosphere URANUS