Astronomy Final

Card Set Information

Astronomy Final
2012-04-26 15:40:41
Astronomy Final Exam

Astronomy test of terms from whole year.
Show Answers:

  1. Define Science:
    The logical, organized search for an explanation about natural phenomena.
  2. What is the Scientific Method, list its steps in correct order, and who is given credit for the idea?
    • A method for solving problems made by Galileo Galilei.
    • State Problem
    • Research Problem
    • State a Working Hypothesis
    • Test Hypothesis
    • Conclusion
  3. Define Theory
    Best explanation for our present level of understanding supported by a large body of reproducible data
  4. ___________ is the alternative to scientific thought.
    Superstitious Beliefs
  5. List the members of the human line (genus, species)
    • Homo habilis
    • Homo erectus
    • Homo sapiens
  6. Define Astronomy
    Scientific study of position, motion, composition, physical properties of celestrial objects, and origin and structure of the Universe.
  7. ___________ particles vibrate at 90o to the direction that the wave travels and ___________ particles vibrate parallel to the direction that the wave travels.
    • Transverse Waves
    • Compressional Waves
  8. Name 3 ways in which the direction of a wave can be changed:
    • Reflection
    • Refraction
    • Diffraction
  9. ___________ is a massless, chargeless, indivisible sub-atomic particle of electromagnetic radiation.
  10. What is meant by the dual nature of light?
    When light is behaving like a wave, it has no particle-like properties, when light is behaving like a particle, it has no wave-like properties.
  11. What does E=mc2 mean?
    Matter and light are interchangeable
  12. Name the components of the electromagnetic spectrum in correct order:
    Gamma, X-Ray, Ultraviolet, Visible light, Infared, Radio Waves
  13. Name the spectral colors in correct order:
    Red, Orange, Yellow, Green, Blue, Indigo, Violet
  14. What does a telescope do?
    A device that makes objects appear closer, larger, more detailed, brighter.
  15. Give a statement of Kepler's 1st Law of Planetary Motion:
    Planets travel about the Sun in elliptic orbits.
  16. Give a statement of Kepler's 2nd Law of Planetary Motion:
    In a single planet's orbit the closer a planet is to the Sun, the faster it travels; and the farther away it is from the Sun, the slower it travels.
  17. Give a statement of Kepler's 3rd Law of Planetary Motion:
    For a system of planets the closer a planet is to the Sun the faster its average speed is.
  18. Define a Day:
    The lenght of time it takes for a planet to spin one time on its axis.
  19. Define a Year:
    The lenght of time it takes for a planet to travel one time about the Sun.
  20. Define a Month:
    Moon circles the Earth about once a month.
  21. Define a Week:
    One of four lunar phases.
  22. What is the difference between Prograde and Retrograde Rotation?
    Prograde Rotation: Spin counter-clockwise when viewed from north pole so Sun rises in East and sets in West, most planets including Earth, while Retrograde Rotation: Spin clockwise so Sun rises in West and sets in East when viewed from norht pole.
  23. The Earth is wobbling on its rotation axis making one complete wobble every ____________ years and positions the Earth's rotational axis such that _____________, the last star in the handle of the Little Dipper, is presently the "North Star".
    • 25,800
    • Polaris
  24. Why are there Seasons on Earth?
    Due to the 23.5o tilt of Earth's rotation axis to the Earth's ecliptic.
  25. What is the side of the Moon we see called and why do we see only one side?
    • The Near Side
    • Due to the Moon's synchronous rotation about the Earth.
  26. What is the difference between a waxing and waning Moon?
    • Waxing: lunar disk visible and growing larger.
    • Waning: lunar disk visible and growing smaller.
  27. Give a statement that explains relative motion:
    All motion is relative to the observer's frame of reference.
  28. __________ is the Earth's orbital plane.
  29. What is the Solar System comprised of?
    The Sun, the 9 planets and their moons, asteroids, and comets.
  30. _________ an orbiting celestial body's closest approach to the Sun and __________ an orbiting celestial body's farthest approach to the Sun.
    • Perihelion
    • Aphelion
  31. All of the planets orbit the Sun in a ____________ direction when viewed from the "north side" of the Solar System.
  32. Name the Terrestrial Planets and list 4 general features they share in common:
    • Mercury, Venus, Earth, Mars
    • Closest to the Sun
    • Small, relatively dense
    • No or few moons
    • No rings
  33. Name the Jovian Planets and list 4 general features they share in common:
    • Jupiter, Saturn, Uranus, Neptune
    • Large, low density
    • Many moons
    • All have rings
    • Very fast rotation
  34. How far is the Earth from the Sun?
    93,000,000 miles which is 1AU
  35. _________ is the closest star to the Earth outside of the Solar System and it is a distance of __________ away.
    • Alpha-centuri
    • 4.25 light years
  36. The accepted age of the Earth (and the Solar System) is _______________________.
    4.6 b.y.
  37. How did the Moon form?
    Moon formed in another region of the Solar System as a Mars-sized planetesimal which had a grazing collision with the Earth.
  38. The Earth's crust is in motion due to ____________ in the mantle.
  39. How is the Earth's magnetic field formed?
    Independent movement of Inner Core generates an electric current in the core and, all electrical currents generate magnetic fields about their conductors (core).
  40. The ____________ and the _____________ form when charged particles released from the Sun ionize gases in the Earth's upper atmosphere.
    • Aurora Borealis (Northern Lights)
    • Aurora Australis (Southern Lights)
  41. What is a Solar Eclipse?
    Moon passes between Earth and Sun casting a shadow on Earth's surface; therefore, the Moon eclipses the Sun.
  42. What is a Lunar Eclipse?
    Moon moves into Earth's shadow and becomes dark because cannot reflect sunlight; therefore, the Earth eclipses the Moon.
  43. What are asteroids?
    Small planetairy bodies that orbit the Sun in a belt between Mars and Juiter.
  44. When and what caused the extinction of the dinosaur and 3/4 of all species on Earth?
    65,000,000 years ago when a 10-km size asteroid hit the Earth created an explosion equal to several billion nuclear explosions a global fire and a winter that lasted several years.
  45. ____________ and _______________ are ocean planets of liquid hydrogen and liquid helium.
    • Jupiter
    • Saturn
  46. __________ and ___________ are icy slush planets.
    • Uranus
    • Neptune
  47. ______________, one of Jupiter's moons, is the only other place in the Solar System besides the Earth where active volcanoes occur; furthermore, they erupt molten sulfur lava.
  48. Pluto is no longer considered to be a planet; Pluto and its moon Charon are now classified as a(n) ________________.
    Astroidal double
  49. ________________ icy planetesimals beyond Pluto and are concentrated in a loosely defined group called the ____________.
    • Comets
    • Oort Cloud
  50. Comets orbiting the Sun form a _____________ and are not confined to the ecliptic.
    Spherical shell
  51. Give 3 unique features of Mars:
    • Atmosphere contains oxygen
    • 1 Martian day about 24 hours
    • Polar Ice Caps
  52. Give 3 unique features of Jupiter:
    • Largest of all planets, 72 times the mass of all other planets combined.
    • Lightning observed in the atmosphere.
    • Great Red Spot (and other spots) -giant eddies; first observed by Galileo.
  53. Give 3 unique features of Saturn:
    • Pronounced polar flattening and equatorial bulge- due to rapid rotation and fluid planet.
    • Density- planet with the lowest density of all planets; density less than that of water.
    • Best developed system of rings of all planets.
  54. The Sun contains _______________ of the mass of the entire Solar System.
  55. Why is the size, shape, and luminosity of the Sun constant?
    The Sun remains stable because a balance exists between the outward push caused by thermal pressure and the inward pull due to gravity.
  56. The temperature of the Sun's surface is ____________ oC and the core's temperature is ____________ oC.
    • 6,000
    • 15,000,000
  57. What is thermo nuclear fusion?
    The joining of light nuclei in to heavy nucleus.
  58. What are the requisites of thermonuclear fusion?
    • Matter int he plasma state
    • High temperatures
    • High Pressure
    • Adequete confinement time
  59. All Main-Sequence Stars are ______________- fusing stars where 4 ___________ nuclei are fused into 1 ___________ nucleus.
    • Hydrogen
    • Hydrogen
    • Helium
  60. The Sun is _______________ years old and has enough fuel to continue for another _____________ years.
    • 4.6 billion
    • 5 billion
  61. The _____________ is the site of thermonuclear fusion in a star like our Sun.
  62. ________________ a unit of length roughly equal to 6 trillion miles.
    Light Year
  63. 90% of the observable stars are ______________.
    Main- Sequence Stars
  64. All of a star's intrinsic properties can be related to its _______________.
  65. What is the chemical composition of the Sun (with relative abundance)?
    • 92% hydrogen
    • 7.8% helium
    • 0.2% all other naturally ocurring elements
  66. Define Brown Dwarfs
    < 0.07 Solar Masses, failed stars
  67. Define Red Dwarfs
    0.07 - 0.4 Mo, Spectral class M, P+ - P+ chain reaction
  68. Define Sun like stars
    0.4 - 3 Mo, Spectral classes K-F, P+- P+ chain reaction
  69. Define Upper Main Sequence Stars
    3 - >9 Mo, Spectral classes F-O, CNO-cycle reaction
  70. The life expectancy of a ________________ is from 60-100 billion years and the Universe is only _____________ billion years old so all of them that have ever formed are still in existence.
    • Red Dwarf
    • 15 billion
  71. What is a Red Giant?
    Large, Cool star which has an inert core supported by degenerate electron-gas pressure surrounded by fusing shells.
  72. What is a Horizontal Branch Star?
    Large relatively hot stars which have fusion in their cores; they fuse the heavy elements from carbon to iron.
  73. For a White Dwarf to form, the stellar remnant must be ____________ solar masses.
  74. For a Neutron Star to form, the stellar remnant must be between ___________ solar masses.
    1.4 - 3.0
  75. The Neutron Star is supported by _______________
    The outward push of degenerate neutron gas pressure.
  76. If the stellar remnant is _____________ solar masses, nothing can support the core forming a Black Hole.
  77. What is a Black Hole?
    A stellar remnant with "zero radius" and "infinite density."
  78. The "surface" of the Sun is the ______________.
  79. Define Galaxy:
    A great concentration of billions of stars that orbit a common center and move through space as a single unit; the largest "single objects" in the Universe.
  80. The Solar System is a member of the ______________ Galaxy which is a(n) _______________ galaxy approximately ______________ years old.
    • Milky Way
    • Spiral
    • 14 billion
  81. What is the structure of a galaxy?
    • Nucleus
    • Galactic Disk
    • Halo
  82. What is the difference between a Population I Star and a Population II Star?
    • Population I stars are young main-sequence stars in the galactic disk, contain short-lived OB types, chemically enriched in heavy elements.
    • Population II stars are very old stars that are in the Halo and are not chemically enriched in heavy elements.
  83. The Solar System moves in a ____________ direction about the galactic nucleus when viewed from the north side of the Sun where 1 revolution takes _____________.
    • Clockwise
    • 225 million years
  84. Name the types of galaxies:
    • Elliptical
    • Spiral
    • Barred Spiral
    • Irregular
  85. What happens when galaxies collide?
    As galaxies collide, there is little chance that stars will collide because the distance between stars within a galaxy is too great; however, this will change their courses.
  86. ______________ - most galaxies are found in small groups that are gravitationally bound to each other so orbit a common center and move through Outer Space as a single unit.
    Galactic Clusters
  87. _____________ - the most distant observable objects that are proto-galaxies 12 billion light-years away from the Earth; 1000 time brighter than a normal galaxy.
  88. Define Cosmology:
    The scientific study of the origin, evolution, and structure of the Universe.
  89. The age of the Universe is estimated to be _____________ years old.
    15 billion
  90. What are the 2 fundamental properties of the Universe?
    • The curvature of the space-time continuum
    • The expansion of the Universe
  91. What is the difference between an Open and Closed Universe?
    • Universe is Open means expansion of the Universe continues to infinite time. Inflationary Universe Theory (Big Bang Theory)
    • Universe is Closed means expansion ceases and gravity causes the Universe to contract reforming the singularity. Oscillating Universe Theory (Bang, Bang, Bang Theory)
  92. What is the Big Bang?
    Creation marking the beginning of energy, matter, time, and universal expansion.
  93. What are UFO's?
    Unidentified Flying Objects, most are reflections off airplanes and weather balloons, or due to atmospheric phenomena like mirages and ball lightning.
  94. What are ET's?
    Extra-Terrestrials, aliens from other celestrial objects, they almost certainly exist as carbon-based intelligent life that conforms to the cell theory.
  95. Why is intersetellar travel unlikely?
    Space is too vast and expensive to cross.
  96. Name the possible ways life may have originated on the Earth and identify which one is (ones are) scientifically testable:
    • Extraterrestrial origin
    • Special creation by a divine force
    • Life originated on an abiotic Earth from inanimate matter; the only idea permitting testable hypothesis
  97. List the characteristics that all life shares in common:
    • All life is carbon based
    • All life conforms to the Cell Theory
    • All life experiences growth, metabolism
    • All life reproduces itself and passes on traits through heredity
    • All life responds to stimuli
  98. Define fossil:
    Any evidence of past life preserved in the rock record.
  99. Define the Theory of Biological Evolution:
    Extinction with replacement with respect to species.
  100. List the body of evidence that supports the Theory of Biological Evolution:
    • Law of Superposition
    • Law of Faunal Succession
    • Uniformitarianism
    • Genetics
    • Radiometric age dates that verify the depth of geologic time
  101. List Darwin's contributions to the Theory of Biological Evolution:
    • Migration
    • Isolation
    • Adaptation
    • Genetic Mutation
    • Natural Selection
    • Diversification
    • May lead to new species
  102. ___________ makes possible what seems impossible.
  103. Define Natural Selection:
    Struggle to survive and only the fit survive to reproduce and pass on genetic traits.
  104. What does SETI stand for and explain what it is?
    The search for Extraterrestrial Intelligence trying to intercept stray radio transmissions from alien civilizations.