Deck 19: Universe

Question 1

The number of galaxies in the universe seems to be about

A)200.
B)200,000.
C)200 million.
D)200 billion.

Answer 1

200 billion.

Question 2

Magnetic fields in our galaxy trap

A)cosmic rays.
B)radio waves.
C)spectral lines.
D)meteoroids.

Answer 2

cosmic rays.

Question 3

Galaxies

A)have a variety of shapes.
B)are evenly distributed in space.
C)are moving closer to one another.
D)rarely contain more than one or two million stars.

Answer 3

have a variety of shapes.

Question 4

All spiral galaxies apparently

A)are rotating.
B)are contracting.
C)are expanding.
D)consist entirely of Population II stars.

Question 5

The ratio of dark matter to ordinary matter in our galaxy is about

A)1:1.
B)2:1.
C)6:1.
D)25:1.

Question 6

Fast electrons that move through magnetic fields produce

A)cosmic rays.
B)radio waves.
C)red shifts.
D)quasars.

Question 7

Our galaxy is shaped roughly like a

A)bunch of grapes.
B)football.
C)fried egg.
D)salami.

Question 8

Molecules in space can be identified from their emissions of

A)light waves.
B)radio waves.
C)cosmic waves.
D)X-rays.

Question 9

The stars in the disk of our galaxy are mostly distributed

A)uniformly.
B)at random.
C)in 1 spiral arm.
D)in 2 spiral arms.

Question 10

The Milky Way is a

A)globular duster.
B)nearby galaxy.
C)galaxy with the sun at its center.
D)galaxy with the sun about 2/3 of the distance from its center.

Question 11

The stars in our galaxy

A)move entirely at random.
B)move toward its center.
C)move away from its center.
D)revolve around its center.

Question 12

The stars in the universe are

A)approximately evenly spaced.
B)concentrated near its center.
C)grouped in widely separated galaxies.
D)irregularly distributed.

Question 13

The stars in globular clusters

A)are relatively close together.
B)have an average spacing like that of stars in the galactic disk.
C)are relatively far apart.
D)form spiral arms.

Question 14

The sun is

A)a Population I star.
B)a Population II star.
C)different from Population I and II stars.
D)a member of a globular cluster.

Question 15

The "dark matter" that all galaxies apparently contain

A)consists of antimatter.
B)consists of cosmic rays.
C)consists of dead stars.
D)is of unknown nature.

Question 16

The number of stars in our galaxy is approximately

A)10,000.
B)10 million.
C)1 billion.
D)100 billion.

Question 17

Emissions of various kinds from near the center of the Milky Way galaxy suggests the presence of a

A)quasar.
B)globular cluster.
C)black hole.
D)galactic nebula.

Question 18

Compared with the Population I stars in the disk of our galaxy, the Population II stars in the globular clusters around it are

A)younger.
B)about the same age.
C)older.
D)Any of these choices are correct.

Question 19

Interstellar space in our galaxy

A)is completely empty.
B)is completely empty except for clouds of gas and dust.
C)contains about 1 atom or molecule per cm³.
D)contains about 1 atom or molecule per cm³ between denser clouds of gas and dust.

Question 20

Individual stars outside our galaxy

A)can be seen with the naked eye.
B)can be seen only with a telescope.
C)cannot be seen even with a telescope.
D)are all members of Population II.

Question 21

Information about the origin of the universe does not come from the

A)fact that spiral galaxies rotate.
B)red shifts in galactic spectra.
C)relative abundances of hydrogen and helium.
D)cosmic background radiation.

Question 22

Quasars

A)are weak sources of light and radio waves.
B)are large in view of the energy they emit.
C)show relatively small red shifts, which suggests they are not far away.
D)seem to have massive black holes at their centers.

Question 23

Galactic spectra show

A)red and blue shifts.
B)red shifts of the same magnitude.
C)red shifts that decrease with distance.
D)red shifts that increase with distance.

Question 24

The proportionality between the recession speeds of the galaxies and their distances from the earth is known as

A)Hess's Law.
B)Herschel's Law.
C)Hubble's Law.
D)Hersey's Law.

Question 25

In a "closed" universe

A)expansion of the universe will continue forever.
B)no additional new stars will form.
C)the universe will neither expand nor collapse.
D)expansion will stop and the universe will ultimately collapse.

Question 26

Primary cosmic rays consist of

A)atomic nuclei, mainly protons.
B)neutral atoms, mainly of hydrogen.
C)molecules.
D)electrons.

Question 27

Primary cosmic rays are characteristic phenomena of the

A)solar system.
B)galaxy.
C)regions between the galaxies.
D)entire universe.

Question 28

Present evidence suggests that the universe

A)will expand forever.
B)will eventually stop expanding and then remain a fixed size.
C)will eventually stop expanding and then contract.
D)has just begun to contract.

Question 29

Dark energy

A)is the energy equivalent of dark matter.
B)is the energy of black holes.
C)is the energy of neutrinos.
D)has an unknown nature as yet.

Question 30

The most distant galaxies are receding at speeds that are

A)much less than the speed of light.
B)not far from the speed of light.
C)equal to the speed of light.
D)greater than the speed of light.

Question 31

The energy that reaches the earth in cosmic rays is comparable to the energy that reaches the earth in

A)sunlight.
B)moonlight.
C)starlight.
D)radio waves.

Question 32

The expansion of the universe apparently

A)has always occurred at the same rate.
B)is currently slowing down.
C)is currently speeding up.
D)has come to a stop.

Question 33

The galaxies in the universe are distributed

A)uniformly.
B)randomly.
C)in groups, groups of groups, and so on.
D)in spiral arms.

Question 34

In the universe today there

A)seems to be no antimatter.
B)is some antimatter but less than the amount of matter.
C)are equal amounts of antimatter and matter.
D)is more antimatter than matter.

Question 35

Considering matter and energy together, the smallest component of the universe seems to be

A)electromagnetic radiation of various kinds.
B)ordinary matter.
C)dark matter.
D)dark energy.

Question 36

Considering matter and energy together, the largest component of the universe seems to be

A)electromagnetic radiation of various kinds.
B)ordinary matter.
C)dark matter.
D)dark energy.

Question 37

The Doppler shifting of radiation from the early universe has resulted in today's universe being bathed in a sea of

A)cosmic rays.
B)X-rays.
C)radio waves.
D)infrared waves.

Question 38

Some, and perhaps all, spiral galaxies have at their centers

A)quasars.
B)pulsars.
C)black holes.
D)globular star clusters.

Question 39

In the light of current evidence, a reasonable figure for the age of the universe is

A)13.7 million years.
B)13.7 billion years.
C)100 billion years.
D)15 trillion years.

Question 40

The "big bang" refers to the origin of

A)the sun.
B)the solar system.
C)our galaxy.
D)the universe.

Question 41

Immediately after the big bang, the universe contained

A)only matter.
B)equal amounts of matter and antimatter.
C)slightly more matter than antimatter.
D)slightly more antimatter than matter.

Question 42

The heavy elements in the earth were formed in

A)the sun.
B)the big bang.
C)supernova explosions.
D)white dwarfs.

Question 43

Studies of the cosmic background radiation suggest that matter in the early universe

A)was uniformly distributed.
B)had small irregularities that grew into today's galaxies.
C)had large irregularities that grew into today's galaxies.
D)formed spiral arms like those in today's galaxies.

Question 44

The planets and their satellites

A)were formed in space and captured by the sun.
B)were formed from material ejected by the sun after its formation.
C)were formed inside the sun and later ejected.
D)came into being at the same time as the sun.

Question 45

Nearly all the helium in the universe was formed in

A)the first few minutes after the big bang.
B)the interior of stars.
C)supernova explosions.
D)black holes.

Question 46

The cosmic background radiation today

A)is present only in galaxies.
B)is present everywhere in the universe.
C)accounts for less of the radiation in the universe than starlight.
D)is visible as a faint glow in the sky on dark nights.

Question 47

The number of planets outside the solar system that have thus far been detected is

A)5.
B)9.
C)50.
D)over 100.

Question 48

Planetary systems are probably

A)very rare in the universe.
B)present around many stars.
C)present around all stars.
D)present only around stars that rotate rapidly.

Question 49

Communications with planets outside the solar system are most likely to be achieved using

A)spacecraft of the kind that went to the moon.
B)spacecraft that travel with the speed of light.
C)spacecraft that travel faster than light.
D)radio waves.