Multiple Choice Identify the letter of the choice that best completes the statement or answers the question.
1. Most star names, such as Aldebaran and Betelgeuse are
a. Latin. b. Greek. c. Arabic. d. English. e. Italian. [answerC]
2. During a total lunar eclipse, which of the following are true?
I. The photosphere of the sun is obscured by the moon. II. The moon is in Earth's umbra. III. The moon is new. IV. The moon is full.
a. I, III b. II, IV c. I, II, III d. II, III e. I, II, III, IV [answerB]
3. What is the angle between the noon sun on the winter solstice and the southern horizon for an observer at a latitude of 38° N? a. 38° b.52° c. 75.5° d. 28.5° e. 14.5° [answerD]
4. Galileo's observations of the gibbous phase of Venus proved a. that Venus orbited the sun. b. that Earth orbited the sun. c. that all of the planets orbited the sun. d. that the moon orbited Earth. e. that Venus had an atmosphere. [answerA]
5. An atom that is excited a. is also ionized. b. is an isotope. c. has had its electron moved to the lowest energy level. d. can emit a photon when the electron moves to a lower energy level. e. can emit a photon when the electron moves to a higher energy level. [answerD]
6. Why don't we see hydrogen Balmer lines in the spectra of stars with temperatures of 3,200 K?
a. There is no hydrogen in stars this cool. b. The stars are hot enough that most of the hydrogen is ionized and the atoms cannot absorb energy. c. These stars are so cool that nearly all of the hydrogen atoms are in the ground state. d. Stars of this temperature are too cool to produce an absorption spectrum. e. Stars of this temperature are too hot to produce an absorption spectrum. [answerC]
8. The sun's magnetic field is evident in the looped shapes of
a. solar flares. b. sunspots. c. the corona. d. granules. e. prominences. [answerE]
9. As the moon covers the solar disk during a solar eclipse, a flash spectrum of the sun's chromosphere can be recorded. This flash spectrum reveals an emission spectrum and provides information on the properties of the chromosphere. As the moon moves from the inner chromosphere to the outer chromosphere, the spectral lines present in the flash spectrum change. What is going on in the chromosphere that produces the changes in the flash spectrum?
I. The temperature of the chromosphere decreases as the distance from the photosphere increases. II. The temperature of the chromosphere increases as the distance from the photosphere increases. III. The density of the chromosphere decreases as the distance from the photosphere increases. IV. The density of the chromosphere increases as the distance from the photosphere increases.
a. I & III b. I & IV c. II & III d. II & IV e. I [answerC]
10. d Circini is an O 8.5 V star. Based on this information which of the following are true?
I. Circini has a surface temperature less than the sun. II. Circini has a diameter that is greater than that of the sun. III. Circini is more luminous than the sun. IV. Circini is located near the upper left hand corner in the HR diagram.
a. I & II b. II & IV c. II, III, & IV d. I, II, & III e. I, II, III, & IV [answerC]
11. The density of a __________ is greater than the density of a __________.
a. white dwarf; neutron star b. neutron star; black hole c. pulsar; neutron star d. pulsar; white dwarf e. white dwarf; black hole [answerD]
12. The rotation curve of a galaxy can be used to determine
a. the relative number of hot young stars in the galaxy. b. the relative amount of gas and dust in the galaxy. c. the radius of the galaxy. d. the luminosity of the galaxy. e. the mass of the galaxy. [answerE]
13. __________ is (are) observed when light from a distant quasar travels past a massive galaxy between us and the quasar, and this light is focused to form two or more images of the same quasar.
a. A double-lobed radio galaxy b. Superluminal expansion c. The gravitational lens effect d. A blazar e. Gravitational waves [answerC]
14. Seyfert galaxies
a. are more common in close pairs of galaxies than in isolated systems. b. emit more energy at x-ray, ultraviolet, infrared, or radio wavelengths than normal spiral galaxies. c. generally show red shifts greater than 6. d. a and b e. a, b and c [answerD]
15. If a galaxy is found receding from us at 894 km/sec and it is located at a distance of 12 Mpc, what is the age of the universe if the universe is flat?
a. about 20 billion years b. about 1.3 billion years c. about 13 billion years d. about 9 billion years e. about 90 billion years [answerD]
16. 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 [answerA]
17. __________ are believed to have formed on Mercury when the planet's interior cooled and shrank.
a. Jumbled terrain b. The highlands c. Maria d. Lobate scarps e. Sinuous rilles [answerD]
18. One hypothesis suggested to explain the uniform age of the surface of Venus is that
a. Venus' surface is 4 billion years old and has not been affected by flooding or slow evolution. b. Venus' surface is made of rocks that are much harder than Earth's and thus last longer. c.Venus periodically goes through a catastrophic melting of the entire surface. d. Venus' clouds protect it from meteorites so that very few impacts occur to change its surface. e. dust storms deposit large amount of dust on the surface making it appear of uniform age. [answerC]
19. The moon's distance from Earth is measured very accurately by bouncing a laser beam off of a small mirror left on the surface of the moon. If a laser is fired at the moon and the signal returns in 2.6 seconds, what is the distance to the moon?
a. 390,000 km b. 390,000 m c. 780,000 km d. 780,000 m e. 1,600,000 m [answerA]
20. The number of communicative civilizations in our galaxy is limited by
a. the size of the average planet. b. the survival of technological societies. c. 21-cm radiation. d. their distance from Earth. e. the number of high mass stars in the galaxy. [answerB]
Completion Complete each sentence or statement.
21. Our galaxy is part of a small cluster of approximately 2 dozen galaxies known as the __________.[answerLocal Group]
22. Earth's rotation axis __________ slowly so that in a few thousand years Polaris will no longer be the North Star.[answerprecesses]
23. Most of the light we see coming from the sun originates in the __________.[answerphtosphere]
24. The __________ shows that sunspots are associated with magnetic activity.[answerZeeman Effect]
25. The pressure of an interstellar gas cloud depends on the clouds __________ and __________.[answertemperature; density]
26. The maximum mass of a white dwarf is __________ solar masses.[answer1.4]
27. The ____[answerlighthouse]______ theory describes pulsars as rotating neutron stars with strong magnetic fields that confine high speed charged particles in two beams emanating from the magnetic poles of the neutron star.
28. A(n) _______[answerx-ray burster]___ periodically emits large amounts of x-ray radiation as material accretes around a neutron star or black hole.
29. ___[answerdisk]_______ of the galaxy contains population I stars, open clusters, and gas clouds.
30. Measuring the Doppler shift of material at various distances from the center of a galaxy can be used to construct a(n) _____[answerrotation curve]_____ for that galaxy.
31. ______[answerS0]____ galaxies have a definite disk component, but contain no evidence of spiral pattern, few hot young stars, and little gas and dust.
32. _____[answerType I]_____ Seyfert galaxies are very luminous at x-ray and ultraviolet wavelengths and have broad emission lines in their spectra.
33. A(n) ____[answerblazar or BL Lac object]______ is observed if our line of sight is along the rotation axis of an active galactic nucleus.
34. The spectrum of a(n) _____[answerquasar]_____ consists of a continuum and a few highly red shifted emission lines of due to hydrogen.
35. A(n) [answercatastrophic] theory of the formation of the solar system uses sudden events that drastically alter the form of the early solar system.
36. ____[answerOzone]______ is responsible for absorbing ultraviolet radiation in Earth's upper atmosphere.
37.____[answerS or Stress]______ waves are seismic waves that do not travel through Earth's liquid core.
38. __[answerMaria]________ are great lava flows covering 17% of the lunar surface.
39. The terrestrial planet with the oldest surface is ______[answermercury]____.
40. The portion of the electromagnetic spectrum between the 21 cm line of neutral hydrogen and the 18 cm line of OH is known as the ___[answerwater hole]_______.
True/False Indicate whether the sentence or statement is true or false.[answerA]
____ 41. The sun is a star in the Milky Way Galaxy.[answerT]
____ 42. The celestial equator always crosses the horizon at the east point and west point.[answerT]
____ 43. A total lunar eclipse is visible only from the path of [answerA].
____ 44. If you were on the moon during a total lunar eclipse, the sun would be hidden behind Earth.[answerA]
____ 45. A scientific model can never be exactly correct.[answerF]
____ 46. Light can behave as a particle or as a wave [answerT].
____ 47. Hydrogen alpha is the longest wavelength Balmer line.[answerT]
____ 48. In the sun, rising currents of hot gas below the photosphere cause granulation.[answerT]
____ 49. The location of a star in the HR diagram indicates its temperature and intrinsic brightness.[answerT]
____ 50. The more massive star in a binary system is always farthest from the center of mass.of the gas.[answerF]
____ 51. The pressure of a gas depends on the temperature and density of the gas.[answerT]
____ 52. Neutron stars were first discovered in the 1930s.[answerF]
____ 53. We expect neutron stars to spin rapidly because they conserve angular momentum.[answerT]
____ 54. The event horizon marks the boundary within which the density is roughly the same as that of the atomic nucleus.[answerF]
____ 55. Shapley found the distance to the center of the galaxy by studying the distance to open clusters.[answerF]
____ 56. The density wave theory explains spurs and branches along the spiral arms.[answerF]
____ 57. When particles in the solar nebula grew large enough, they stopped growing by accretion and began growing by condensation.[answerF]
____ 58. Mercury's smooth plains are probably the oldest parts of the crust.[answerF]
____ 59. Flow channels on Venus suggest it was once rich in water.[answerF]
____ 60. Venus is very hot because its atmosphere is rich in carbon dioxide[answerT].