Deck 24: Stars, Space, and Galaxies

Question 1

The ____ was the formation of helium nuclei by nuclear fusion during the first 8.5 minutes in the life of the Universe.

A) main sequence
B) primordial nucleosynthesis
C) supernova
D) cosmic background radiation

Answer 1

B

Question 2

Within a star, gravity pulls particles inward, but at the same time, ____________________ energy drives them outward.

Answer 2

fusion

Question 3

A(n) ____________________ is a distance equal to 3.26 light-years.

Answer 3

parsec

Question 4

The way a star will end its life depends on its ____.

A) orbiting planets
B) rate of rotation
C) mass
D) distance from Earth

Question 5

A graph that plots absolute stellar luminosity versus temperature is called a(n) ____________________ diagram.

Question 6

____________________ are comparatively cool, dark regions on the Sun's surface caused by magnetic disturbances.

Question 7

A cloud of interstellar gas and dust is called a ____.

A) nebula
B) photosphere
C) star fog
D) sunspot

Question 8

When a star larger than 1.44 solar masses dies, a(n) ____________________ explosion occurs after helium fusion has ended and after iron fusion has occurred.

Question 9

The ____________________ brightness of a star decreases the farther you are from it.

Question 10

The cosmic background radiation is ____ radiation that began traveling through space when the Universe was about 300,000 years old.

A) low-energy, microwave
B) high-energy, microwave
C) low-energy, ultraviolet
D) high-energy, ultraviolet

Question 11

Jets of gas called ____________________ shoot upward from the chromosphere, looking like flames from a burning log.

Question 12

The Sun is composed primarily of hydrogen and ____________________.

Question 13

In the ____________________ zone of a star, hot gas rises, cools, and then sinks in huge, circulating cells.

Question 14

Spherical clouds of dust and gas, known as a(n) ____________________, surround the Milky Way's galactic disk.

Question 15

The mass of our galaxy calculated from its rotational speed is much larger than the mass of all the known matter within. Astronomers have proposed that ____________________ may provide the additional mass to explain this difference.

Question 16

The ____________________ zone is the inner part of a star surrounding the core where energy is transmitted by absorption and emission.

Question 17

The big bang occurred ____ years ago.

A) 520 million
B) nearly 4.6 billion
C) 6 billion
D) nearly 14 billion

Question 18

One ____________________ is the distance traveled by light in a year, or 9.5 trillion kilometers.

Question 19

A small, extremely dense star that emits regular, closely spaced radio signals is a(n) ____________________.

Question 20

A dying star as massive as our Sun that will eventually shrink until its diameter is approximately that of Earth, and will glow solely from its residual heat produced during past eras, is called a(n) ____________________.

Question 21

What do astrophysicists call the poorly understood repulsive force that causes the expansion of the Universe to accelerate?

A) dark energy
B) dark mass
C) the quasar force
D) entropy

Question 22

The surface of the Sun that we see from Earth is the ____.

A) convective zone
B) photosphere
C) chromosphere
D) spicule

Question 23

All the known elements heavier than iron form during the ____.

A) life of a main sequence star
B) big bang
C) white dwarf phase of a star
D) explosion of supernovae

Question 24

The radiation emitted by stars, galaxies, and quasars is known as ____.

A) first generation energy
B) second generation energy
C) the big bang
D) cosmic background radiation

Question 25

Population II stars are originally composed of ____.

A) mostly heavy elements inherited from population I stars like our Sun
B) only hydrogen and helium
C) mostly hydrogen and heavy elements
D) mostly helium with small amounts of hydrogen and smaller amounts of heavy elements

Question 26

Almost two-thirds of the bright galaxies in our region of the Universe, including the Milky Way, are ____.

A) lens-shaped galaxies
B) elliptical galaxies
C) spiral galaxies
D) irregular galaxies

Question 27

Neutron stars are ____.

A) dense stars where neutrons are fusing together to form iron
B) composed of approximately 75% hydrogen, 24% helium, and 1% other elements
C) so dense that light cannot escape from them
D) compressed so tightly that the electrons and protons in the star are squeezed together to form neutrons

Question 28

In the ____ model, the gravitational force of the Universe is not sufficient to stop the current expansion and the galaxies will continue to fly apart forever.

A) closed Universe
B) open Universe
C) infinite Universe
D) cyclical Universe

Question 29

Astronomers believe that a ____ must lie at the center of our galaxy, the Milky Way.

A) globular cluster
B) galactic halo
C) prominence
D) black hole

Question 30

A ____ is a red, flame-like jet of gas rising from the Sun's corona that can be held aloft for weeks or months by the Sun's magnetic fields.

A) prominence
B) granule
C) radiative zone
D) nebula

Question 31

Which list correctly orders the layers of the Sun from the center outward?

A) photosphere, core, corona, and chromosphere
B) corona, core, chromosphere, and photosphere
C) core, corona, chromosphere, and photosphere
D) core, photosphere, chromosphere, and corona

Question 32

Black holes are black because ____.

A) dust surrounding the center completely obscures the light in the center
B) their gravitational field is so intense that light cannot escape
C) they do not produce any radiation
D) they are regions where absolutely no matter is present

Question 33

Which list correctly orders different regions of the Sun from highest temperature to lowest temperature?

A) core → corona → photosphere
B) core → photosphere → corona
C) photosphere → core → corona
D) corona → core → photosphere

Question 34

The cosmic microwave background radiation is an example of ____.

A) third generation energy
B) energy released by solar prominences
C) Hertzsprung-Russell energy
D) first generation energy

Question 35

The major reason for differences in temperature and luminosities among main-sequence stars is that some ____.

A) have a higher ratio of hydrogen to helium
B) formed earlier in the history of the Universe
C) are more massive than others
D) rotate faster than others

Question 36

All main-sequence stars are composed primarily of ____ and ____.

A) helium; carbon
B) hydrogen; oxygen
C) hydrogen; helium
D) helium; oxygen

Question 37

A pulsar is a ____ that emits a pulsating radio signal.

A) red giant
B) white dwarf
C) neutron star
D) black hole

Question 38

Why does fusion cease in a star once iron forms?

A) Iron reacts with hydrogen, preventing any more hydrogen fusion.
B) Iron is too dense and the star collapses inward.
C) Iron fusion absorbs energy rather than releasing energy.
D) Iron fusion releases too much energy, blowing the star apart.

Question 39

The ____ brightness of a star is how bright a star would appear if it were 10 parsec away from Earth.

A) absolute
B) relative
C) apparent
D) main

Question 40

A ____ is a large volume of space containing many billions of stars held together by their mutual gravitational attraction.

A) galaxy
B) pulsar
C) quasar
D) black hole

Question 41

A concentration of older stars that shared a common origin and are held together by gravity, lying within the galactic halo of a spiral galaxy is called a(n) ____.

A) prominence
B) white dwarf
C) globular cluster
D) emission nebular

Question 42

Helium fusion requires a higher temperature than hydrogen fusion because ____.

A) helium has to be driven into the outer layers of a star for fusion to occur
B) helium bonds with carbon at the temperature of hydrogen fusion
C) the repulsion between two helium nuclei is much greater
D) hydrogen must be driven off so it doesn't interfere with the helium nuclei

Question 43

When we look at close objects, we see what is happening now, but when we look at distant objects, we see what happens in the future.

Question 44

The Universe was perfectly homogeneous, or uniform, in its infancy.

Question 45

Hubble's law states that the ____.

A) most distant galaxies are moving outward at the greatest speeds
B) most distant galaxies are moving toward us at the greatest speeds
C) closest galaxies are moving toward us at the greatest speeds
D) closest galaxies are moving away from us at the greatest speeds

Question 46

The expansion of the Universe is slowing down, and it will eventually collapse on itself.

Question 47

Until about 300,000 years after the big bang, atoms could not form because the temperature of the Universe was so hot.

Question 48

Five billion years from now, the hydrogen in our Sun's core will be exhausted and the Sun will expand into a red giant.

Question 49

Before the Universe cooled enough for atoms to exist, about 300,000 years after the big bang, the Universe was fog-like or opaque because photons could never move far in any direction without being absorbed.

Question 50

If a star were orbiting a black hole, great masses of gas from the star would be sucked into the black hole, to disappear forever.

Question 51

The Sun is a population II star.

Question 52

Because they do not emit light, it's impossible for astronomers to determine whether black holes really exist.

Question 53

Blue stars are hotter than red stars.

Question 54

The expansion of the Universe provides a piece of evidence in support of the big bang theory.

Question 55

The carbon in our bodies was created during the big bang.

Question 56

If we can see a quasar that is 8 billion light-years away, it must still exist.

Question 57

Main sequence stars fall along a sinuous diagonal band across the Hertzsprung-Russell diagram.

Question 58

___ are short-lived releases of high-energy radiation emanating the death throes of massive stars, when a neutron star is sucked into a black hole, or when two neutron stars collide to form a black hole.

A) Gamma ray bursts
B) Spicules
C) Parsecs
D) Dark energy pulses

Question 59

The process of absorption, emission, and convection slows down photons traveling from the Sun's core so much that it takes about one million years to reach the photosphere.

Question 60

The three-dimensional shape of our galaxy, the Milky Way, is like a ____.

A) wave
B) cylinder
C) bowl
D) disk

Question 61

What do solar prominences look like?

Question 62

Describe the gravitation force and size of the Sun.

Question 63

Describe the radiative and convective zones.

Question 64

How big is the Sun's core and how much hydrogen fuel does it have left?

Question 65

Describe the photosphere.

Question 66

What is the composition of the Sun?

Question 67

Describe sunspots.

Question 68

What are the three lines of logic and evidence that supports the big bang theory?

Question 69

How and when did an initially uniform, homogeneous Universe concentrate into stars, galaxies, and clusters?

Question 70

Describe the Hertzsprung-Russell diagram.

Question 71

Describe a supernova.

Question 72

How is all the information that we know about the Sun derived?

Question 73

What is a parsec?

Question 74

Define apparent brightness and absolute brightness.

Question 75

Describe a red giant.

Question 76

What powers the Sun?

Question 77

How far is a light-year?

Question 78

Explain what will happen to the Sun in five billion years from now.

Question 79

What is the chromosphere?

Question 80

What is first-generation energy?