Exploring the Universe, Fall 00, Test 2

NAME______

Please indicate the best answer to the following questions on the answer sheet provided. Each question is worth 2 points.

1. The oldest rocks found on Earth are about ______years old.

a. 10 billion, b. 5.3 billion, c. 4.6 billion, d. 3.9 billion, e.6.2 million

2. Which of the following is not a characteristic of the terrestrial planets?

a. low average density, b. orbits inside the asteroids

c. craters in old surfaces, d. small diameters, e. very few satellites

3. A ______is a solar system object that enters Earth's atmosphere and becomes very hot due to friction between the object and Earth's atmosphere.

a. asteroid, b. meteor, c. comet, d. meteoroid, e. planetesimal

4. The condensation sequence suggests that ______should condense closest to the sun.

a. Jovian planets, b. metals and metal oxides, c. silicates

d. ices of water, methane, and ammonia, e. low density materials

5. The planets all lie in nearly the same plane resulting in a disk like structure for the solar system. This disk like structure is believed to exist because

a. the original solar nebulae had a disk-like structure.

b. the bipolar flow from the young sun cleared all material out of the nebula except that in the disk.

c. Jupiter's gravity was great enough to pull all of the other planets to the plane of its orbit.

d. planetesimals settled into the plane.

e. the sun's magnetic field slowed down the rotation of the solar nebula.

6. Which one of the following objects is most like the planetesimals that formed in the solar nebular?

a. asteroids, b. Earth, c. Saturn, d. Venus, e. the sun

7. The large planetesimals would have grown faster than the smaller planetesimals because

a. they were moving faster in their orbits than the smaller planetesimals.

b. their stronger gravity would pull in more material.

c. there was more material located near them that could be accreted.

d. the smaller planetesimals were covered by a layer of material that was lost during collisions.

e. all of these

8. Earth's magnetic field is generated by the dynamo effect in the

a. molten metallic core, b. solid central core,

c. plastic mantle, d. the crust, e. aurora

9. The greenhouse effect occurs because

a. carbon dioxide is transparent to visible light and opaque to infrared radiation.

b. carbon dioxide is transparent to infrared radiation and opaque to ultraviolet radiation.

c. ozone is transparent to infrared radiation and opaque to ultraviolet radiation.

d. ozone is transparent to visible light and opaque to infrared radiation.

e. the sun emits more infrared radiation than ultraviolet radiation.

10. The gas that is most responsible for the greenhouse effect on Earth is

a. oxygen (O2), b. nitrogen (N2), c. carbon dioxide (CO2),

d. ozone (O3), e. ammonia (NH3)

11. Earth possesses few visible craters and the moon possesses many. This is because

a. Earth formed later than the moon and, therefore hasn't encountered as many meteoroids.

b. the moon doesn't have an atmosphere that could burn up many of the meteorites before impacting.

c. erosion and plate tectonics have slowly removed evidence of past cratering on Earth.

d. all of the above

e. Both the moon doesn't have an atmosphere that could burn up many of the meteorites before impacting, and erosion and plate tectonics have slowly removed evidence of past cratering on Earth.

12. The ozone layer is

a. transparent to ultraviolet radiation.

b. opaque to ultraviolet radiation.

c. opaque to visible light.

d. opaque to infrared radiation.

e. responsible for producing most of the oxygen that animal life needs.

13. The energy that moves the plates of Earth's crust comes from

a. the solar wind.

b. convection from the hot interior.

c. tides in the oceans.

d. friction between wind and the land surface.

e. Earth's magnetic field.

14. The lunar maria are

a. the lava plains of the lunar lowlands.

b. the smooth plateaus of the lunar highlands.

c. less than one billion years old.

d. moving plates of lunar crust.

e. older than the lunar highlands.

15. That Mercury has a large iron core is evidenced by

a. the large lobate scarps.

b. the large mean density of Mercury.

c. the lava flows near Caloris Basin.

d. all of the above

e. none of these

16. Which hypothesis concerning the formation of the moon makes predictions that best fit the observed lunar data?

a. The large impact hypothesis

b. The fission hypothesis

c. The capture hypothesis

d. The condensation hypothesis

e. The regolith hypothesis

17. The geology of Venus appears to be dominated by

a. volcanism.

b. plate tectonics.

c. erosion by flowing water.

d. impact cratering.

e. strip mining.

18. The flow patterns found on the surface of Mars suggest

a. that Mars is a water-rich world.

b. that the climate on Mars was different in the past.

c. that volcanism is occurring on Mars.

d. that the polar caps are made of water.

19. Which of the solar system objects listed below is most similar to Earth in terms of mass and density?

a. Mercury, b. Moon, c. Venus, d. Mars, e. Deimos

20. Jupiter does not have

a. a hot interior.

b. convection occurring in its atmosphere.

c. crustal plates on its surface.

d. a dynamo effect.

e. any rings.

21. Europa has few craters because

a. it is protected from impacts by Jupiter's gravity.

b. it does not have a solid surface.

c. it has erased craters nearly as fast as they have formed.

d. its surface is not strong enough to support craters.

e. it keeps one face always pointed toward Jupiter which screens it from incoming meteorites.

22. Which of the Galilean satellites are geologically active?

a. Io and Callisto

b. Ganymede and Titan

c. Titan and Callisto

d. Europa and Io

e. Ganymede and Callisto

23. The rotation of Uranus is peculiar in that

a. it is much slower than is typical for Jovian planets.

b. it is much faster than is typical for Jovian planets.

c. the equator rotates much faster than the poles.

d. the axis is nearly parallel to the plane of its orbit.

e. it can not be measure because Uranus has no surface features.

24. The rings of Uranus were discovered

a. during an occultation of a star.

b. during an eclipse of one of the moons by the rings.

c. during an eclipse of Uranus by the rings.

d. as Uranus and the rings passed behind Jupiter.

e. by Voyager 1.

25. A bit of matter that enters Earth's atmosphere and survives to reach the ground is called

a. a meteor.

b. a meteoroid.

c. a meteorite.

d. a minor planet.

e. an asteroid.

26. A meteor shower is produced when

a. a large number of sporadic meteors are observed.

b. Earth passes through the asteroid belt.

c. massive particles are carried outward from the sun by the solar wind and enter Earth's atmosphere.

d. Earth passes through the orbital path of a comet.

e. meteors cause condensation in the upper atmosphere that leads to early morning rains.


27. Most of the asteroids orbit the sun in a belt between the orbits of

a. Venus and Earth, b. Earth and Mars, c. Jupiter and Saturn.

d. Mercury and Venus, e. Mars and Jupiter.

28. An asteroid could produce an iron core and a silicate mantle if it

a. differentiated, b. outgassed, c. condensed, d. accreted, e. sublimed.

29. The gas tail of a comet always

a. trails behind the head along the orbital path.

b. extends ahead of the head along the orbital path.

c. points toward the sun.

d. points away from the sun.

e. points perpendicular to the orbital path.

30. The short-period comets do not have randomly oriented orbits because

a. they are affected by the sun's gravity.

b. they are affected by the solar wind.

c. they formed in the Kuiper Belt, a belt shaped region in the plane of the solar system.

d. their orbits are altered by the drag of their tails in the solar wind.

e. they all were originally objects ejected from the asteroid belt.

31. The impact of a large comet with Earth has been suggested to have caused the extinction of the dinosaurs. The impact site of this comet is in or near

a. Iowa

b. Hudson Bay

c. Crater Lake, Oregon

d. Canberra Australia

e. Chicxulub Mexico

32. The graph below plots the escape velocity of each planet along the vertical axis and its surface temperature along the horizontal. The lines plotted in the figure are the average speeds of gas particles as a function of temperature for various gases. Which of the gases plotted in the diagram could be retained in the atmosphere of Mars?

a. only CO2

b. only NH3

c. CO2, NH3, and O2

d. only H2

e. H2 and He

33. This planet's density is so small it could float in a bathtub if you had one big enough.

a) Venus, b) Earth, c) Jupiter, d) Saturn

34. The greenhouse effect has raised the temperature of this planet several hundred degrees.

a) Venus, b) Earth, c) Jupiter, d) Saturn

35. This planet has a distinctive northern and southern hemisphere with winds that blow large amounts of dust around.

a) Venus, b) Mars, c) Earth, d) Mercury

36. This planet has multi-colored cloud bands and a storm which has raged for over 300 years.

a) Venus, b) Jupiter, c) Saturn, d) Neptune

37. Most think this planet is not really a planet after all, but we will keep the designation for historical reasons.

a) Mercury, b) Neptune, c) Uranus, d) Pluto

38. We thought this was our sister planet with clouds and such, but we didn't realize it rains sulfuric acid there.

a) Venus, b) Mars, c) Jupiter, d) Neptune

39. When it comes to density, we rule the solar system.

a) Terrestrial planets, b) Jovian planets, c) asteroids, d) comets

40. When it comes to total mass, we rule the solar system

a) Terrestrial planets, b) Jovian planets, c) asteroids, d) comets

41. We would have formed a planet, but Jupiter's gravity kept disrupting us.

a) asteroids, b) comets, c) Kuiper belt objects, d) Oort cloud objects

42. People all over the world use to fear us, but we are so fragile we couldn't even hold our own weight on

a) comets, b) meteors, c) asteroids, d) aurora

43. The Roche limit is

a) distance from the Sun where life cannot exist

b) distance from a planet where moons cannot exist

c) the boundary layer between the solar system and the rest of the galaxy

d) the maximum distance a spacecraft can be sent from Earth

44. What produces aurora?

a) chemical reactions in the upper atmosphere, b) meteors

c) collisions of high energy particles with atmospheric gas, d) reflection of Sunlight by high clouds

45. What accounts for the seasonal changes in the coloration of certain regions on Mars?

a) the covering and uncovering of the regions by dust, b) melting and refreezing of permafrost

c) changes in cloud cover, d) migration of large herds of quadrupeds

46. What is the order of the four Galilean moons of Jupiter in increasing distance from the planet?

a) Ganymede, Callisto, Io, Europa, b) Callisto, Io, Europa, Ganymede

c) Io, Europa, Ganymede, Callisto, d) Europa, Ganymede, Callisto

47. The light given off by a comet:

a) is reflected sunlight,

b) is caused by chemical reactions set in place by the intense sunlight

c) due to nuclear energy from the comet's nucleus

d) due to frictional forces in the Earth's atmosphere


48. The orbital planes of the planets in the solar system are

a) randomly orientated, b) each inclined by 10 degrees more than the previous one

c) all lie in the same plane, d) constantly change

49. What is the most abundant constitute in the Earth's atmosphere

a) Oxygen, b) CO2, c) Hydrogen, d) Nitrogen

50. How do we know the Earth has a liquid core?

a) it sloshes around when the Earth rotates,

b) only compression waves make it through,

c) we have drilled down and sampled some,

d) we can see it at the bottom of some oceans