ASTR 135.02 Final Exam 2001.12.19 – form A

Name:_________________________ID number:____________________

For multiple choice questions, circle the letter of the most correct answer.

1)      It is now generally accepted that extremely large numbers of incipient comets surround the solar system in a spherical shell nearly one light-year in radius called the

a)      Asteroid belt

b)      Kuiper Belt

c)      Oort cloud

d)      Halley Sphere

e)      Bode zone

2)      What is remarkable about comet Halley?

a)      It crashed into Jupiter in 1994.

b)      It was the brightest comet in recent years.

c)      It came close to hitting Earth.

d)      It broke apart due to tidal forces.

e)      It was the first comet recognized to be periodic.

3)      If a fragment of interplanetary matter survives its descent to Earth, and you later pick it up, you are holding a

a)      meteoroid

b)      meteorite

c)      meteor

d)      bolide

e)      chondrite

4)      When Earth passes through the region of space occupied by a dead or dying periodic comet’s orbit we experience a(n)

a)      aurorae

b)      explosion

c)      meteor fall

d)      meteor shower

e)      meteor radiant

5)      The size of object that is considered to impart the greatest risk to humans is a

a)      Meteoroidal impactor, less than a few meters across

b)      Small impactor, less than 1 km across

c)      Large impactor, more than 10 km across

d)      Medim impactor, a few km across

6)      The bottom layer of the solar atmosphere is the

a)      corona

b)      photosphere

c)      chromosphere

d)      convective envelope

e)      solar wind

7)      The spiky atmospheric layer just above the sun’s visible layer is the

a)      corona

b)      photosphere

c)      chromosphere

d)      convective envelope

e)      solar wind

8)      If you consider the sun as a blackbody, its λmax is in the ______ part of the spectrum

a)      ultraviolet

b)      visible

c)      infrared

d)      microwave

e)      X-ray

9)      Solar surface granulation is caused by

a)      radiation

b)      convection

c)      conduction

d)      thermal flux

e)      radioactivity

10)   The most correct name for the process that powers the sun is

a)      thermonuclear fission

b)      gravity

c)      thermonuclear fusion

d)      thermodynamic equilibrium

e)      oxidation

11)   Compared to surrounding regions on the solar “surface,” sunspots are

a)      hotter

b)      cooler

c)      deficient in helium

d)      at higher altitude

e)      at lower altitude

12)   Categories of stars based on their respective spectra are called

a)      absorption groups

b)      spectral groups

c)      spectral types

d)      line groups

e)      luminosity classes

13)   Stellar parallax is

a)      how the star moves across the sky

b)      why light rays go parallel to each other

c)      a method for getting star distances

d)      the reason stars do not collide

e)      measured in parsecs

14)   The magnitude that a star would have if it were placed at the standard 10-parsec distance is its

a)      apparent magnitude

b)      parallax

c)      brightness

d)      luminosity

e)      absolute magnitude

15)   A star at 1000 parsecs distance has a brightness of 16 femtowatts/m2. An identical star at 500 parsecs would have a brightness of

a)      8 femtowatts/m2

b)      32 femtowatts/m2

c)      4 femtowatts/m2

d)      64 femtowatts/m2

e)      16 femtowatts/m2

16)   Which of the following stars has the hottest photospheric temperature?

a)      K

b)      O

c)      G

d)      A

e)      Brown dwarf

17)   It is March. Approximately, what is the right ascension of the sun?

a)      0 h

b)      6 h

c)      12 h

d)      18 h

18)   It is late June. Approximately, what is the right ascension of the moon if it is full?

a)      0 h

b)      6 h

c)      12 h

d)      18

19)   It is late December. Approximately, what is the sun’s declination?

a)      –66.6°

b)      –23.4°


d)      23.4°

e)      66.6°

20)   At sunset one evening you notice the moon high in the sky directly south. What phase is it in?

a)      new

b)      first quarter

c)      full

d)      last quarter

21)   As seen from Pullman, when will an upright flagpole cast no shadow because the sun is directly above the flagpole?

a)      Every day at noon.

b)      On the first day of summer.

c)      On the first day of winter

d)      On both the spring and fall equinoxes.

e)      Never.

22)   The period-luminosity relation applies to which kind of variable star?

a)      Cepheid variables

b)      RR Lyrae variables

c)      Mira variables

d)      Cataclysmic variables

e)      Delta Scuti variables

23)   If one RR Lyrae variable has the pulsation period as another RR Lyrae variable but appears 4 magnitudes brighter, then its absolute magnitude is

a)      4 magnitudes fainter

b)      4 magnitudes brighter

c)      1 magnitude fainter

d)      ¼ magnitudes fainter

e)      the same

24)   Star clusters with dozens to thousands of stars containing relatively large amounts of heavier elements are called

a)      globular clusters

b)      galaxy clusters

c)      open clusters

d)      heavy clusters

25)   Most globular clusters are located in the Milky Way’s

a)      spheroid

b)      disk

c)      neither

d)      both

26)   Young stars in the Milky Way are located in the

a)      spheroid

b)      disk

c)      neither

d)      both

27)   Nearly circular, coplanar star orbits are the hallmark of the

a)      spheroid

b)      disk

c)      neither

d)      both

28)   A star cluster’s age is found by finding

a)      the RR Lyrae variable stars

b)      the most massive main-sequence star

c)      the brightest red giant

d)      the cool end of the main sequence

29)   Which main sequence star will live the longest time?

a)      A

b)      F

c)      M

d)      O

e)      B

30)   Main sequence stars produce energy by destroying

a)      Carbon

b)      Helium

c)      Hydrogen

d)      Oxygen

31)   The process of building heavier atoms from lighter ones is called

a)      atom building.

b)      nuclear mitosis

c)      nucleosynthesis

d)      ionization

e)      chemistry

32)   When a low-mass star nears the end of its life, it ejects shells of gas into space forming a(n)

a)      dust cloud

b)      asteroid belt

c)      planetary nebula

d)      protoplanet

e)      solar system

33)   Jocelyn Bell discovered a new type of celestial object in 1967 with a radio telescope. After the possibility that it was a signal from an alien civilization was discarded, these objects were named

a)      radio stars

b)      quasars

c)      binary stars

d)      supernovae

e)      pulsars

34)   Black holes, neutron stars, and white dwarfs can all be occasionally found surrounded by a disk of material gathered up from a(n)

a)      presolar nebula

b)      companion star

c)      planetary nebula

d)      solar wind

e)      supernova remnant

35)   If, after a supernova, the stellar remnant at the center masses about two solar masses, the result is a

a)      white dwarf

b)      neutron star

c)      black hole

d)      brown dwarf

36)   Matter flowing into the gravitational field of a black hole will form a(n)

a)      bipolar flow

b)      accretion disk

c)      planet

d)      singularity

e)      asteroid belt

37)   Which type of nebulae is associated with a newly formed star cluster?

a)      dark nebula

b)      H II region

c)      planetary nebula

d)      solar nebula

38)   What kind of objects did Harlow Shapley study to find that the sun was many thousand parsecs from the center of the Milky Way?

a)      open clusters

b)      galaxy clusters

c)      globular clusters

d)      elliptical clusters

39)   The hydrogen in an H II region is predominantly

a)      neutral

b)      ionized

c)      molecular

d)      bonded with oxygen

40)   Most of the Milky Way’s gas is in the

a)      disk

b)      spheroid

c)      both

d)      neither

41)   He III has two protons and

a)      2 electrons

b)      4 electrons

c)      1 electron

d)      3 electrons

e)      0 electrons

42)   The Hubble “tuning fork” classification system considers what galaxy attribute?

a)      size

b)      shape

c)      luminosity

d)      mass

43)   The small galaxy cluster containing the Milky Way, the Andromeda Galaxy and about 20 smaller galaxies is the

a)      Virgo cluster

b)      Large Magellanic Cloud

c)      Pleiades

d)      Perseus cluster

e)      Local group

44)   Edwin Hubble found the distance to the Andromeda Galaxy by using the inverse-square law on

a)      RR Lyrae variable stars

b)      Cepheid variable stars

c)      Long-period variable stars

d)      Globular clusters

e)      Main-sequence stars

45)   The implication of the “Hubble Law” is that the universe is

a)      expanding

b)      contracting

c)      steady state

d)      finite

e)      infinite

46)   Assuming H = 50 km/s/Mpc, we would expect a galaxy at a distance of 300 million parsecs to have a recessional velocity of

a)      60 km/s

b)      60 Mpc

c)      15000 km/s

d)      15000 Mpc

e)      300 km/s

47)   What is probably at the center of a quasar?

a)      A nucleus

b)      A neutron star

c)      A black hole

d)      A white hole

e)      A cataclysmic variable

48)   A closed universe has density

a)      less than critical density.

b)      equal to critical density.

c)      more than critical density.

d)      zero

49)   The cosmic background radiation was predicted as an outcome of the

a)      Steady-state theory

b)      Theory of General Relativity

c)      Theory of stellar evolution

d)      Big Bang theory

50)   At redshift 1000 the CBR had a temperature of 3000 K. What is its observed temperature?

a)      3000 K

b)      300 K

c)      30 K

d)      3 K

e)      0.3 K

51)   Draw an H-R diagram below. Label the horizontal and vertical axes. Label 4 named regions on the diagram where stars congregate.
















52)   Explain the Fermi paradox.