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WorksheetsWGU Astronomy
Total questions: 140
Worksheet time: 2hrs 45mins
Name
Class
Date
1.
Claudius Ptolemy attempted to explain the motion of the planets mathematically by devising a small circle, the epicycle, rotating along the edge of a larger circle, the deferent.
What was at the center of these circles?
a)
The Earth
b)
The Sun
c)
The Moon
d)
The Void
2.
What is a key distinction between Kepler’s model of the universe compared to previous models?
a)
Kepler was the first to propose that orbits are not perfect circles.
b)
Kepler was the first to propose that the earth orbited around the Sun.
c)
Kepler was the first to propose epicycles as an explanation of retrograde orbits.
d)
Kepler was the first to propose that the universe is expanding.
3.
Which scientist is credited with developing the mathematical framework to accurately describe
the force of gravity and the way forces behave in our universe?
a)
Issac Newton
b)
Johannes Kepler
c)
Tycho Brahe
d)
Hipparchus of Nicaea
4.
Which scientist utilized precision mathematics to develop planetary laws of motion?
a)
Kepler
b)
Copernicus
c)
Erastothenes
d)
Galileo
5.
Which scientist was unable to identify a parallax in his measurements of stellar positions and so
was unable to support a heliocentric model for the Solar System?
a)
Tycho Brahe
b)
Galileo Galilei
c)
Johannes Kepler
d)
Isaac Newton
6.
What did Ptolemy use to explain retrograde motion in his model?
a)
Epicycles and deferent
b)
Elliptical orbits
c)
A Sun-centered universe
d)
Solar parallax
7.
What is one observation Galileo made that was used to support the heliocentric theory?
a)
Phases of Venus
b)
Aurora borealis
c)
Moon phases
d)
Supernovae
8.
Which statement in Kepler’s first law proves planetary motion as a heliocentric model?
a)
Planetary motion shows elliptical orbits.
b)
Planetary motion is always at a constant speed.
c)
Planetary motion is explained as a line joining a planet and Sun, sweeping out equal areas during equal time intervals.
d)
Planetary motion is defined as the square of orbital period of a planet being proportional to the cube of the semi-major axis.
9.
Object A and Object B orbit the Sun. Object A is observed to orbit the Sun every 64.0 years.
Object B is measured to be an average distance of 125.0 AU away from the Sun.
Which statement is true?
a)
Object A is closer to the Sun than Object B.
b)
Object A is further from the Sun than Object B.
c)
Object A and Object B are at the same distance from the Sun.
d)
The distance between the Sun and Object A cannot be determined.
10.
Which comet broke up and bombarded Jupiter in 1994?
a)
Shoemaker-Levy 9
b)
Halley’s Comet
c)
Hale-Bopp
d)
Swift-Tuttle
11.
In the northern hemisphere, the Sun appears to rise and set in the southern part of the sky.
Why is the Sun observed in this part of the sky?
a)
This is due to the Earth’s spin on its axis.
b)
This is due to the Earth’s slight flattening at the poles.
c)
This is due to the Earth’s distance from the Sun.
d)
This is due to the Earth’s revolution around the Sun.
12.
How are absorption spectra produced?
a)
Absorption spectra show dark lines due to wavelengths being absorbed by a cooler medium.
b)
Absorption spectra show a smooth gradient without any gaps.
c)
Absorption spectra show bright lines produced by elements within a star.
d)
Absorption spectra show the rotation of a star.
13.
Ancient astronomers observed some stars that appeared to move very quickly around the
celestial sphere. Sometimes these stars appeared to move backwards with respect to the
celestial sphere.
What objects were these astronomers observing?
a)
Planet
b)
Moon
c)
Comet
d)
Nearby star
14.
What prevents astronomers from observing galaxies in the direction of the constellation
Sagittarius?
a)
The galactic center is in the line of sight.
b)
The Sun is in the line of sight.
c)
It is very close to the horizon.
d)
Gravitational lensing due to dark matter along the line of sight
15.
When observed from Earth, some planets show retrograde motion periodically with respect to
the celestial sphere.
Which planet would a person on Jupiter be able to observe having a retrograde motion?
a)
Saturn
b)
Venus
c)
Earth
d)
Mars
16.
Which electromagnetic wave has the shortest wavelength?
a)
X-Rays
b)
Radio waves
c)
Infrared waves
d)
Ultraviolet waves
17.
The image above shows the electromagnetic spectrum.
Which wavelength corresponds to yellow light?
a)
600 nm
b)
400 nm
c)
500 nm
d)
700 nm
18.
The image above shows the electromagnetic spectrum.
What color would a wavelength of 500 nm produce?
a)
Blue
b)
Purple
c)
Yellow
d)
Red
19.
What has wavelengths measured in meters to hundreds of meters in length?
a)
Radio
b)
Gamma rays
c)
Infrared
d)
Microwave
20.
What is the relationship between the energy of an electromagnetic wave and wavelength?
a)
The energy of an electromagnetic wave is inversely proportional to the wavelength.
b)
The energy of an electromagnetic wave is proportional to the wavelength.
c)
The energy of an electromagnetic wave is independent of the wavelength.
d)
The energy of an electromagnetic wave is equal to the wavelength.
21.
What is lower energy than red light?
a)
Infrared
b)
Gamma rays
c)
Blue light
d)
Yellow light
22.
Why are optical telescopes often placed in mountainous areas?
a)
To mitigate atmospheric blurring
b)
To collect stronger radio waves
c)
To utilize energy from the ionosphere
d)
To benefit from the high albedo of snow
23.
Which telescope uses a mirror to collect light?
a)
Reflecting
b)
Refracting
c)
Atmospheric
d)
Radio
24.
Which astronomical technology connects many small telescopes to create the effect of one large
one?
a)
Interferometry
b)
Spectroscopy
c)
Photometry
d)
Cosmology
25.
Which astronomical technology sharpens an existing telescope image by removing atmospheric
distortions?
a)
Adaptive optics
b)
Interferometry
c)
Spectroscopy
d)
Photon detection
26.
What determines the light-gathering power of a telescope?
a)
The area of the primary mirror or lens
b)
The radius of the primary mirror or lens
c)
The focal length of the primary mirror or lens
d)
The curvature of the primary mirror or lens
27.
Which type of telescope needs to be launched high in the atmosphere or out of the atmosphere
to avoid problems like water vapor absorption and the apparent glow of Earth’s atmosphere?
a)
Infrared telescope
b)
Reflecting telescope
c)
Refracting telescope
d)
X-ray telescope
28.
Which telescope type makes use of cylindrical mirrors to create shallow reflection of the
incoming radiation onto the detectors?
a)
X-ray telescopes
b)
Optical telescopes
c)
Infrared telescopes
d)
Radio telescopes
29.
Which action will produce the Doppler Effect?
a)
Observer moving toward a sound source
b)
Sound source moving toward an observer
c)
Light from a distant galaxy as it moves away from Earth
d)
All of the above
30.
How does the frequency and wavelength of a wave source change when it moves towards an
observer?
a)
The wavelength decreases while the frequency increases.
b)
The wavelength increases while the frequency decreases.
c)
The wavelength increases and the frequency increases.
d)
The wavelength decreases and the frequency decreases.
31.
A person hears a distant police siren and the pitch is increasing.
What does the increasing pitch inform that person about the movement of the siren source?
a)
The source is moving toward the person.
b)
The source is moving away from the person.
c)
The source has stopped moving.
d)
The source has slowed down.
32.
What concept does redshifted starlight support?
a)
Objects in space are moving away from each other.
b)
Objects in the universe are not moving.
c)
Objects in space are moving toward each other.
d)
Objects in space cannot be measured.
33.
What would an observer at the side of a road hear as a car passes close by at a very high speed?
a)
The frequency of the sound would increase while the car is approaching, and decrease after
the car has passed by.
b)
The frequency of the sound would decrease while the car is approaching, and decrease after the car has passed by.
c)
The volume of the sound would decrease while the car is approaching, and increase after the car
has passed by.
d)
The volume of the sound would increase both as the car is approaching and after it has passed by.
34.
What is the cause of a sonic boom?
a)
An object producing sound waves is traveling faster than the speed of sound.
b)
An object producing sound waves is traveling slower than the speed of sound.
c)
An object producing light waves is traveling slower than the speed of light.
d)
An object producing light waves is traveling faster than the speed of light.
35.
An important spectral line usually occurs at 656.3 nanometers. Astronomers measure light from
one side of a galaxy and measure this spectral line at 680.3 nanometers. They measure light
from the other side of the galaxy and measure the same line at 632.3 nanometers. Light from
the center of the galaxy is measured to have this same line at 656.1 nanometers.
What can astronomers conclude from this data?
a)
The galaxy is rotating quickly.
b)
The galaxy is moving sideways very slowly.
c)
The galaxy is not moving at all.
d)
The galaxy is moving away from us very quickly.
36.
Star A has a temperature of 5500 K and Star B of 3500 K.
What does Planck’s law explain about the amount of energy a photon carries with frequency of
their electromagnetic waves?
a)
Star A has a higher frequency of electromagnetic wave than Star B.
b)
Star B has a higher frequency of electromagnetic wave than Star A.
c)
Star A is less luminous than Star B.
d)
Star A is more massive than Star B.
37.
How is the approximate temperature of a star determined?
a)
By the color of the star, thus frequency of photons being emitted
b)
By the brightness of the star, thus frequency of photons being emitted
c)
By the size of the star, thus number of photons being emitted
d)
By the distance of the star, thus frequency of photons being emitted
38.
Which wavelengths are successfully observed using ground-based telescopes?
a)
Visible and radio waves
b)
Infrared and ultraviolet waves
c)
Gamma and x-rays
d)
Microwave and gamma rays
39.
How can Plank’s law for a star’s temperature be summarized?
a)
Temperature is inversely proportional to wavelength.
b)
Temperature is proportional to wavelength.
c)
Temperature is inversely proportional to frequency.
d)
Temperature is proportional to frequency.
40.
What wavelength of light would be associated with a star with a temperature over 25,000 K?
a)
450 nm
b)
500 nm
c)
550 nm
d)
600 nm
41.
Which group contains only planets that have retained a portion of their primordial atmosphere?
a)
Uranus and Neptune
b)
Earth and Mars
c)
Mercury and Jupiter
d)
Venus and Saturn
42.
What is the frost line that divides the terrestrial and Jovian planets?
a)
It was the boundary in the solar nebula beyond which ices could condense.
b)
It is the line on Martian mountains where frost forms.
c)
It was the line where rings could form around planets.
d)
It is the boundary between layers in a planet’s atmosphere.
43.
Why do scientists believe there could be life on Jupiter’s moon, Europa?
a)
It has a very large, ice-covered ocean.
b)
It is located very close to the Sun and is very warm.
c)
Radio waves coming from the moon have been detected.
d)
A spacecraft landed on Europa and detected microbes.
44.
During the formation of our solar system, small rocky planets formed near the Sun while large
gas planets like Jupiter formed farther out in the solar system.
Why are gas planets unable to form in the inner solar system?
a)
Solar radiation pressure pushed all the gas out of the inner solar system, leaving behind only
heavier elements.
b)
Differentiation causes heavier materials to move closer to the Sun, leaving the lighter gases in the outskirts of the solar system.
c)
All the gas that was present in the inner solar system accreted onto the Sun.
d)
Because of the proximity to the Sun, gas planets that form too close to the Sun will accrete onto the Sun, losing all their mass.
45.
What mechanism caused the heavy bombardment to occur after the planets were formed?
a)
Leftover material was flung into the inner solar system by Jovian planets.
b)
Leftover material was pulled into the inner solar system by the Sun.
c)
Leftover material slowly migrated towards the Sun due to decaying orbits.
d)
Leftover material was pushed into the inner solar system by collisions.
46.
What is the point between the orbits of Mars and Jupiter that separates the area where volatile
ices remain solid, allowing Jovian planets and the terrestrial planets to form?
a)
Frost line
b)
Kuiper belt
c)
Asteroid belt
d)
Lagrange point
47.
Which explanation correctly summarizes the “Jovian Problem”?
a)
How large gas planets can form quickly enough, before the disks of raw material evaporate
b)
How large gas planets migrate out to the outer solar system
c)
How the cores of large gas planets form at such high temperatures and pressures
d)
How the atmospheres of large gas planets can contain so much hydrogen
48.
Which planet is indicated by the red arrow in this model of the solar system?
a)
Uranus
b)
Neptune
c)
Saturn
d)
Jupiter
49.
What type of celestial object is indicated by the red arrow in this model of the solar system?
a)
Jovian planet
b)
Terrestrial planet
c)
Minor planet
d)
Exo-planet
50.
Which planet is indicated by the red arrow in this model of the solar system?
a)
Venus
b)
Earth
c)
Mercury
d)
Mars
51.
Comets are large, icy, and rocky objects.
Where within the solar system would one be most likely to find comets?
a)
Within the Oort cloud
b)
Near the terrestrial planets
c)
Within the asteroid belt
d)
Near the Jovian planets
52.
What effect can a large moon’s gravity have on the shape of its host planet?
a)
A large moon can create a tidal bulge on the planet it is orbiting.
b)
A large moon can cause the planet to take on a round shape.
c)
A large moon can cause mountains to form on the near side of the planet.
d)
A large moon can pull off parts of the planet.
53.
What would happen to Earth if there were no moon?
a)
Oceans would have less tidal fluctuation.
b)
Earth’s orbit would become more stable.
c)
Climate would be the same everywhere on the planet.
d)
Ring systems would likely form around the Earth.
54.
Which of Earth’s layers is the thickest?
a)
Mantle
b)
Outer core
c)
Crust
d)
Inner core
55.
Which layer of the Earth is primarily composed of low-density, solid, silicate minerals and rocks?
a)
Crust
b)
Mantle
c)
Inner core
d)
Outer core
56.
Which process helps lead to the formation of Earth’s magnetic field?
a)
Convection currents within the outer core
b)
Convection currents within the mantle
c)
The impact of the rotation of the Earth on the crust
d)
The impact of the rotation of the Earth on the inner core
57.
Why is ozone in the stratosphere important?
a)
It absorbs ultraviolet light from the sun.
b)
It creates more oxygen.
c)
It increases photosynthesis in plants.
d)
It creates necessary cloud cover.
58.
Which solar system object is typically a few kilometers in diameter, mostly composed of water
and methane ice, and often has two tails?
a)
Comet
b)
Meteor
c)
Asteroid
d)
Dwarf planet
59.
Which solar system object can range in size from one to hundreds of meters in diameter, is
located between Mars and Jupiter, and is mostly made of rock and metal?
a)
Asteroids
b)
Comets
c)
Meteors
d)
Meteoroids
60.
Which non-planetary object is icy, rocky, and dusty with a highly elliptical orbit?
a)
Comet
b)
Moon
c)
Asteroid
d)
Meteoroid
61.
Which stage in evolution will the Sun be starting five billion years from now?
a)
It will slowly start to expand into a red giant star.
b)
It will slowly start to shrink into a main sequence star.
c)
It will burn out to become a black hole.
d)
It will shrink to a white dwarf.
62.
What will be the final fate of the Sun?
a)
A planetary nebula will form with a white dwarf core.
b)
A black hole will form.
c)
A neutron star will form.
d)
A red giant will form.
63.
Where on the Hertzsprung-Russell (HR) diagram are the youngest stars located?
a)
At the top of the main sequence, located on the upper left
b)
At the bottom of the main sequence, located on the lower right
c)
At the lower left off the main sequence
d)
At the upper right off the main sequence
64.
Which luminosity class would be where stars with the largest radii on the H-R diagram are
found?
a)
Class I
b)
Class II
c)
Class III
d)
Class IV
65.
How much of the solar system’s mass is contained in the Sun?
a)
Approximately 99%
b)
Approximately 25%
c)
Approximately 50%
d)
Approximately 75%
66.
Which major event occurs just before a protostar begins fusion and goes into the main
sequence?
a)
It shoots out jets of gas, sometimes several light years long.
b)
It collapses into a neutron star.
c)
It releases clouds of dust and rock.
d)
It forms a disk like a doughnut around its center.
67.
What can cause a nebula to collapse and form a star?
a)
A gravitational or magnetic disturbance can cause the nebula to collapse.
b)
A black hole can cause a disturbance in the nebula.
c)
A nearby drifting planet can cause the gas and dust to clump together.
d)
It occurs when two stars collide.
68.
What can happen if a shock wave from a nearby exploding star reaches a molecular cloud?
a)
Star formation
b)
Gamma ray burst
c)
Supernova
d)
Nebula diffusion
69.
Which quality directly correlates with the lifetime of a star?
a)
Size
b)
Composition
c)
Temperature
d)
Color
70.
What is a small and relatively cool star on the main sequence?
a)
Red dwarf
b)
Brown dwarf
c)
Blue giant
d)
Hypergiant
71.
What only develops from more massive and less common stars and have short lives?
a)
Blue giant
b)
Hypergiant
c)
Main sequence
d)
White dwarf
72.
A large star can start to fuse heavier and heavier elements as it runs out of its supply of
hydrogen and helium.
Which element is the heaviest that can be formed and when it is created leads to the death of
the star?
a)
Iron
b)
Lithium
c)
Xenon
d)
Uranium
73.
Which stage of a star’s life cycle has the longest duration?
a)
Main sequence
b)
Red giant
c)
Planetary nebula
d)
Protostar
74.
Which characteristic do white dwarfs, protostars, and black holes have in common?
a)
All of these objects have no fusion occurring in their cores.
b)
All of these objects fuse elements heavier than hydrogen.
c)
All of these objects are the end result of stellar evolution.
d)
All of these objects are commonly known as compact objects.
75.
During which phase in the life cycle of a Sun-like star would its volume be the lowest?
a)
White dwarf
b)
Protostar
c)
Main sequence
d)
Red giant
76.
Which low-mass stellar remnant is roughly the same mass as the Sun but has a similar radius to
Earth?
a)
White dwarf
b)
Neutron star
c)
Magnetar
d)
Black hole
77.
What will be the fate of a star the size of the Sun when it dies?
a)
It will become a white dwarf.
b)
It will become a black hole.
c)
It will become a brown dwarf.
d)
It will become a blue giant.
78.
What describes the Sun?
a)
Low mass
b)
High mass
c)
Brown dwarf
d)
Blue giant
79.
One way that nuclear fusion occurs within a star’s core is via the proton-proton chain.
What describes the proton-proton chain reaction?
a)
Two hydrogen atoms react to create deuterium; hydrogen and deuterium react to form a
helium atom with a mass of 3; and two of these helium atoms with a mass of 3 react to form a
helium atom with a mass of 4.
b)
Two hydrogen atoms react to create deuterium, and two deuterium atoms react to form a
helium atom with a mass of 4.
c)
Two hydrogen atoms react to create deuterium; hydrogen and deuterium react to form a helium
atom with a mass of 3; and hydrogen reacts with this helium with a mass of 3 to form a helium
atom with a mass of 4.
d)
Two hydrogen atoms react with a helium atom with a mass of 3 to create a helium atom with a
mass of 4 and a hydrogen atom.
80.
What is the dominant fusion process in stars like the Sun?
a)
Proton–proton fusion
b)
CNO (carbon–nitrogen–oxygen) cycle
c)
Helium fusion
d)
Carbon cycle
81.
Which type of galaxy is shown in the picture above?
a)
Elliptical
b)
Spiral
c)
Irregular
d)
Quasar
82.
Where are the young blue stars located in a spiral galaxy?
a)
In the spiral arms
b)
In the bulge
c)
Throughout the galaxy
d)
In between the spiral arms
83.
What does Hubble’s law state about the universe?
a)
The universe has been expanding at the same rate since the big bang.
b)
The universe has been expanding at an increasing rate since the big bang.
c)
The expansion of the universe varies in direction.
d)
The expansion of the universe stopped during the formation of galaxies.
84.
The star Capella is 42.9 light years (13.15 parsecs) away.
What would be the best method to use to determine this star's distance?
a)
Parallax
b)
Cepheid variables
c)
Redshift
d)
Lyrae variables
85.
Which distance measure would be most appropriate to use within the solar system?
a)
Radar
b)
Parallax
c)
Cepheids
d)
Redshift
86.
What is believed to help form all galaxies?
a)
Supermassive black holes
b)
Dark energy
c)
Quasars
d)
Degenerate matter
87.
Approximately how old are the majority of supermassive black holes at the centers of galaxies?
a)
14 billion years old
b)
0.4 billion years old
c)
4 billion years old
d)
24 billion years old
88.
Which characteristic of a supermassive black hole correlates with its surrounding host galaxy?
a)
Mass
b)
Density
c)
Age
d)
Luminosity
89.
What is believed to have helped form the first galaxies?
a)
Supermassive black holes
b)
Dense pockets of dark matter
c)
Explosions of new star formations
d)
Density waves
90.
One theory suggests that supermassive black holes are formed from small black holes that grow
by attracting matter due to gravitational force.
Which term describes this process?
a)
Accretion
b)
Fusion
c)
Differentiation
d)
Contraction
91.
What is in an inertial reference frame?
a)
A Voyager space probe leaving the solar system
b)
A child spinning on a merry-go-round
c)
A race car accelerating on a track
d)
Matter falling into a black hole
92.
A yellow light source falls into a black hole.
What would a distant observer see as the light approaches the event horizon?
a)
The light would be redshifted.
b)
The light would appear brighter due to gravitational lensing.
c)
The light would be blueshifted.
d)
The light would appear to oscillate due to gravitational waves.
93.
Which phenomenon explains the relative passage of time for a fast-moving astronaut against a
slower moving Earth, creating a scenario where an Earthbound observer experiences time
moving more quickly?
a)
Time dilation
b)
Binary time
c)
Spacetime warp
d)
Lookback time
94.
Which example within the solar system showcases the theory of general relativity?
a)
The orbit of Mercury is shifting over time due to its location near the sun.
b)
Jupiter’s atmosphere consists mostly of hydrogen.
c)
The surface of the moon features evidence of ancient bombardment.
d)
Halley’s Comet features multiple tails.
95.
Which situation is evidence for the big bang theory when studying evidence of hot gas from the
beginning of the universe?
a)
Red-shifted light in the radio waves portion of the spectrum
b)
Red-shifted light in the visible portion of the spectrum
c)
Red-shifted light in the X-ray portion of the spectrum
d)
Red-shifted light in the gamma ray portion of the spectrum
96.
What describes the relative speed of the movement of galaxies in the universe?
a)
The farther the galaxy, the faster it recedes from an observer’s viewpoint.
b)
The closer the galaxy, the faster it recedes from an observer’s viewpoint.
c)
The farther the galaxy, the faster it approaches from an observer’s viewpoint.
d)
The closer the galaxy, the faster it approaches from an observer’s viewpoint.
97.
How long ago was the universe created?
a)
13.7 billion years ago
b)
150 million years ago
c)
4.6 billion years ago
d)
30.8 billion years ago
98.
What are the four fundamental forces that emerged right after the big bang?
a)
Gravity, strong nuclear forces, weak nuclear forces, and electromagnetism
b)
Dark energy, dark matter, hydrogen, and helium
c)
Quarks, protons, neutrons, and atoms
d)
Electrons, photons, radiation, and X-rays
99.
Which phenomenon occurs when light passes close to a massive object, causing its path to bend
or curve?
a)
Gravitational lensing
b)
Gravitational redshift
c)
Time dilation
d)
Length contraction
100.
How are main sequence stars in hydrostatic equilibrium?
a)
Hydrogen fuses together to form helium in the core, causing an outward pressure that
balances the gravity force inward due to the star’s mass.
b)
Helium fuses together to form hydrogen in the core, causing an outward pressure that balances
the gravity force inward due to the star’s mass.
c)
Hydrogen fission forms helium in the core, causing an outward pressure that balances the
gravity force inward due to the star’s mass.
d)
Helium fission forms helium in the core, causing an outward pressure that balances the gravity
force inward due to the star’s mass.
101.
Which order of evolution for a main sequence star is correct?
a)
Main sequence, red giant, white dwarf
b)
Main sequence, white dwarf, red giant
c)
White dwarf, main sequence, red giant
d)
Red giant, main sequence, white dwarf
102.
Where on the Hertzsprung-Russell (HR) diagram will the more massive main sequence stars be located?
a)
At high temperatures and luminosity in the upper left
b)
At high temperatures and luminosity in the upper right
c)
At low temperatures and high luminosity in the lower left
d)
At high temperatures and low luminosity in the lower right
103.
Which description identifies the location of a red dwarf on the main sequence branch of the H-R diagram?
a)
At the position nearest the bottom where low luminosity, low mass stars are found.
b)
At the position nearest the top left where high luminosity, high mass stars are found.
c)
At the position nearest the middle where mid luminosity, mid mass stars are found.
d)
At the position nearest to where 1.0 Solar Mass objects would be found.
104.
In which part of the Sun does nuclear fusion take place?
a)
The core
b)
The photosphere
c)
The chromosphere
d)
The corona
105.
How long does the Sun’s sunspot cycle last?
a)
11 years
b)
12 years
c)
22 years
d)
24 years
106.
Why are molecular clouds important to star formation?
a)
They are huge, dense clouds of gas that form hundreds of thousands of stars like the Sun.
b)
They are very small, and each one gives birth to one star.
c)
They are very hot and cause clouds of gas to begin nuclear fusion.
d)
They contain large chains of molecules like DNA and RNA.
107.
Why is a brown dwarf sometimes referred to as a “failed star”?
a)
Because it does not have enough mass to generate nuclear fusion
b)
Because it forms when a black hole collapses
c)
Because it forms from brown and black dust
d)
Because it forms too close to a massive star
108.
What correctly describes a protostar?
a)
Lower temperatures than an ordinary star
b)
High masses of helium at the core
c)
Fission of deuterium in the interior
d)
Visible wavelengths of light prominent
109.
Which color are sun-like main sequence stars in the middle of their lifespans?
a)
Yellow
b)
Red
c)
Orange
d)
Blue
110.
What are substellar objects that occupy the mass range between the heaviest gas giant planets and the lightest stars?
a)
Brown dwarfs
b)
Red dwarfs
c)
Blue giants
d)
Hypergiants
111.
When a star like the Sun depletes its supply of hydrogen and helium, it will collapse. What will the collapsed Sun form into?
a)
White dwarf
b)
Red giant
c)
Blue giant
d)
Black dwarf
112.
Stellar evolution starts with the gravitational collapse of a giant molecular cloud.
What is the rotating sphere of superhot gas that forms known as?
a)
Protostar
b)
Brown dwarf
c)
White dwarf
d)
Main-sequence
113.
Why does fusion not occur in a brown dwarf?
a)
A brown dwarf does not have a high enough mass to fuse hydrogen into helium.
b)
A brown dwarf is made of only very heavy elements that do not fuse easily.
c)
A brown dwarf is in the last stage of a Sun-like star’s life, so electron degeneracy prevents
fusion.
d)
A brown dwarf is too unstable to fuse elements.
114.
Which objects fuse the heaviest elements?
a)
Red supergiants
b)
Main sequence stars
c)
White dwarfs
d)
Red giants
115.
Which type of low-mass object is also known as a failed star?
a)
Brown dwarf
b)
White dwarf
c)
Red giant
d)
Black hole
116.
Which stellar remnant results from a mass that exceeds the Chandrasekhar limit but is less than three solar masses?
a)
Neutron star
b)
White dwarf
c)
Black hole
d)
Brown dwarf
117.
What must happen for a star to move to the main sequence?
a)
It must fuse hydrogen into helium.
b)
It must have more mass than a red giant.
c)
It must exhibit nuclear fission.
d)
It must become more luminous than a white dwarf.
118.
The Sun is currently within the main sequence portion of its life.
What is occurring in the core of a star like the Sun once it reaches the main sequence portion of its life?
a)
Four hydrogen atoms fuse to create one helium atom.
b)
Two hydrogen atoms fuse to create one helium atom.
c)
One helium atom splits to create two hydrogen atoms.
d)
One helium atom splits to create four hydrogen atoms.
119.
The iron group is the upper limit of energy yield by fusion.
How are post-iron elements formed in stars?
a)
Supernova explosions
b)
Proton-proton fusion
c)
Helium fusion
d)
Carbon cycle
120.
The main sequence state of a star's life is the hydrogen core fusion stage.
What is the first stage after the main sequence?
a)
Hydrogen shell fusion
b)
Carbon core fusion
c)
Helium shell fusion
d)
Iron core fusion
121.
Which type of object is shown in the picture above?
a)
Irregular galaxy
b)
Elliptical galaxy
c)
Spiral galaxy
d)
Quasar
122.
What does the Doppler redshift tell astronomers about the universe?
a)
The universe is expanding as galaxies move away faster with distance from Earth.
b)
The universe is shrinking as galaxies move faster toward Earth.
c)
The universe is unstable as the galaxies collide with each other.
d)
The galaxies are attracted by gravity into black holes.
123.
How does the transit method detect extrasolar planets?
a)
It detects dimming by the passage of a planet between its star and Earth.
b)
It detects a solar eclipse by the extrasolar planet.
c)
It detects an extrasolar planet as it passes another planet.
d)
It detects reflection from the extrasolar planet from our Sun.
124.
What is the best way to determine the distance to a very distant galaxy?
a)
Type Ia supernovae
b)
Cepheid variables
c)
Tully-Fisher relation
d)
Parallax
125.
Which galaxy type has central supermassive black holes that are not actively feeding?
a)
Inactive
b)
Anemic
c)
Quasar
d)
Seyfert
126.
Which type of emissions are commonly detected from Sagittarius A in the center of the Milky Way galaxy?
a)
Radio
b)
Gamma ray
c)
Infrared
d)
X-ray
127.
Which type of galaxy is often distorted and has tidal tails?
a)
Seyfert
b)
Inactive
c)
Quasar
d)
Anemic
128.
When humans observe a galaxy, they cannot see the supermassive black hole at its center directly. Which characteristic of a supermassive black hole can be used?
a)
Gravity
b)
Luminosity
c)
Density
d)
Mass
129.
**PICTURE** Which feature is indicated by the red arrow in this hypothetical image of a supermassive black
hole at the center of a galaxy?
a)
Accretion disk
b)
Magnetic field lines
c)
Event horizon
d)
Gamma-ray jet
130.
Why would a spaceship not be able to travel directly through the center of a large spiral galaxy?
a)
The galaxy contains a black hole at its center.
b)
The density of stars is too great.
c)
The temperature is too great.
d)
The center of the galaxy is solid.
131.
A spaceship is traveling near the speed of light. A stationary outside observer sees two lights
blinking on the front and back of the ship.
If the outside observer sees the two lights as blinking simultaneously, what would an observer
looking out the window from the center of the ship observe?
a)
The front light blinking first
b)
Both lights blinking simultaneously
c)
The rear light blinking first
d)
Both lights appearing permanently on
132.
Under which circumstance can something travel at the speed of light?
a)
If it has no mass
b)
If it is inside a black hole
c)
If it has infinite mass
d)
If it is passing near a compact object
133.
How would an astronaut’s spaceship appear relative to its direction of motion if time dilation
was occurring?
a)
It would seem shorter.
b)
It would seem hotter.
c)
It would seem dimmer.
d)
It would seem closer.
134.
A space expedition takes crates of medical equipment on its voyage. The mass of these crates of
medical equipment, as measured on Earth, is written on the inventory sheet.
If the spaceship is traveling at close to the speed of light for part of the trip, how does the mass
of the medical equipment at this speed compare to what is written on the inventory?
a)
The mass is greater.
b)
The mass is the same.
c)
The mass is lower.
d)
The mass is 0.
135.
Which term describes the measurement of red-shifted photons from near the creation of the
universe?
a)
Cosmic background radiation
b)
Hubble’s constant
c)
Planetary nebula
d)
Universal soup
136.
What are the first two elements that formed once the universe expanded and cooled?
a)
Hydrogen and helium
b)
Iron and lead
c)
Oxygen and carbon
d)
Lithium and boron
137.
How do astronomers define the observable universe?
a)
The distance beyond which astronomical objects are invisible
b)
The place where the big bang occurred
c)
The average distance between galaxies
d)
The diameter of the universe
138.
What is the inflation theory?
a)
The universe increased dramatically in size in an extremely brief period of time.
b)
There was a time in the past when gravity grew stronger.
c)
The number of galaxies humans see at farther distances is greater than the number seen at
nearer distances.
d)
The diameters of distant galaxies are greater than those near us.
139.
Which phenomenon occurs when a moving clock is observed to run more slowly than a clock
that is in the same room as the observer?
a)
Time dilation
b)
Gravitational redshift
c)
Gravitational lensing
d)
Length contraction
140.
What happens when a star has fused all hydrogen to helium in the core of massive stars?
a)
Helium is fused to heavier elements, such as carbon.
b)
The star’s energy has been used up.
c)
The star instantly becomes a white dwarf.
d)
The star instantly collapses.
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