Question 1

Only about 10% of the mass of the Galaxy is in the form of visible stars,gas,and dust.

Accepted Answer

A) True 
 B)False

Question 2

What useful purpose did RR Lyrae stars serve for Harlow Shapley in locating the galactic center?

Accepted Answer

A)  Their brightness variations allowed accurate distances to be measured. 
B)  They emit copious amounts of infrared radiation and are thus visible through interstellar dust,which obscured visible light. 
C)  They are concentrated in the galactic center and so defined its direction. 
D)  They are important spiral arm tracers and thus defined the shape of the Galaxy. 
A)  Their brightness variations allowed accurate distances to be measured. 
B)  They emit copious amounts of infrared radiation and are thus visible through interstellar dust,which obscured visible light. 
C)  They are concentrated in the galactic center and so defined its direction. 
D)  They are important spiral arm tracers and thus defined the shape of the Galaxy.

Question 3

What is the shape and size of our Galaxy?

Accepted Answer

6 kilopars

Question 4

The central core of the Galaxy is in the direction of

Accepted Answer

A)  the Ring Nebula. 
B)  the North Star. 
C)  Sagittarius A*. 
D)  Orion's belt. 
A)  the Ring Nebula. 
B)  the North Star. 
C)  Sagittarius A*. 
D)  Orion's belt.

Question 5

One proposal for the mysterious dark matter in the Galaxy is that it is made of massive compact halo objects (MACHOs).

Accepted Answer

A) True 
 B)False

Question 6

The period-luminosity relationship for Cepheid variable stars,relating variability to absolute overall brightness,thereby providing identifiable beacons throughout our local space,was discovered by

Accepted Answer

A)  Harlow Shapley. 
B)  Henrietta Leavitt. 
C)  Edwin Hubble. 
D)  Sir Isaac Newton. 
A)  Harlow Shapley. 
B)  Henrietta Leavitt. 
C)  Edwin Hubble. 
D)  Sir Isaac Newton.

Question 7

What is microlensing?

Accepted Answer

A)  The focusing of starlight by the gravitational fields of "small" objects such as brown dwarfs 
B)  The beaming of radiation by accretion disks 
C)  The use of small telescopes to enhance contrast by eliminating scattered light 
D)  The focusing of starlight by planetary atmospheres 
A)  The focusing of starlight by the gravitational fields of "small" objects such as brown dwarfs 
B)  The beaming of radiation by accretion disks 
C)  The use of small telescopes to enhance contrast by eliminating scattered light 
D)  The focusing of starlight by planetary atmospheres

Question 8

"Standard candles," which are important for finding distances to remote galaxies,are

Accepted Answer

A)  standard laboratory light sources with which the brightness of a galaxy can be compared. 
B)  heat sources used for calibrating infrared observations of galaxies. 
C)  stars and other objects of known intrinsic brightness. 
D)  laboratory light sources with a well-known spectrum for calibration of stellar and galactic spectra. 
A)  standard laboratory light sources with which the brightness of a galaxy can be compared. 
B)  heat sources used for calibrating infrared observations of galaxies. 
C)  stars and other objects of known intrinsic brightness. 
D)  laboratory light sources with a well-known spectrum for calibration of stellar and galactic spectra.

Question 9

Observations from what two parts of the electromagnetic spectrum reveal that the Galaxy has spiral arms.

Accepted Answer

A)  Radio and optical observations 
B)  X-ray and microwave observations 
C)  Infrared and ultraviolet observations 
D)  Gamma-ray and microwave observations 
A)  Radio and optical observations 
B)  X-ray and microwave observations 
C)  Infrared and ultraviolet observations 
D)  Gamma-ray and microwave observations

Question 10

The dimensions of the disk of our Milky Way Galaxy are

Accepted Answer

A)  diameter,80,000 light-years;thickness,6500 light-years. 
B)  diameter,6500 light-years;thickness 2000 light-years. 
C)  diameter,2000 light-years;thickness,160,000 light-years. 
D)  diameter,160,000 light-years;thickness,2000 light-years. 
A)  diameter,80,000 light-years;thickness,6500 light-years. 
B)  diameter,6500 light-years;thickness 2000 light-years. 
C)  diameter,2000 light-years;thickness,160,000 light-years. 
D)  diameter,160,000 light-years;thickness,2000 light-years.

Question 11

Flocculent spiral galaxies have spiral arms that are broad,fuzzy,chaotic,and poorly defined and grand-design spiral galaxies have thin,graceful,well-defined spiral arms.

Accepted Answer

A) True 
 B)False

Question 12

The Sun takes about 220 million years to complete one trip around the Galaxy.

Accepted Answer

A) True 
 B)False

Question 13

What is the evidence that a supermassive black hole exists at the center of our Galaxy?

Accepted Answer

7 million solar masses.In addition,X-ray

Question 14

If the Galaxy were spinning like our solar system,stars closer to the center would

Accepted Answer

A)  orbit in much less time than stars farther out. 
B)  orbit in much greater time than stars farther out. 
C)  orbit in the same amount of time as stars closer in. 
D)  eventually fly apart from the immense speed. 
A)  orbit in much less time than stars farther out. 
B)  orbit in much greater time than stars farther out. 
C)  orbit in the same amount of time as stars closer in. 
D)  eventually fly apart from the immense speed.

Question 15

How would astronomers,ancient or modern,use a "standard candle"?

Accepted Answer

A)  They would use its faint light to illuminate the setting dials of their telescopes. 
B)  They would use it to measure time,using its slow but steady melting. 
C)  They would use it to generate a known and extremely reproducible standard spectrum for comparison with stellar spectra. 
D)  They would measure distance by comparing its apparent brightness with its known absolute brightness. 
A)  They would use its faint light to illuminate the setting dials of their telescopes. 
B)  They would use it to measure time,using its slow but steady melting. 
C)  They would use it to generate a known and extremely reproducible standard spectrum for comparison with stellar spectra. 
D)  They would measure distance by comparing its apparent brightness with its known absolute brightness.

Question 16

The significant feature of a Cepheid variable is that there is a relationship between two intrinsic parameters,the first being easily measured,the second being the parameter that is required.These parameters are

Accepted Answer

A)  variation of spectral color and distance to the star. 
B)  period of brightness variation and spectral color. 
C)  period of brightness variation and luminosity. 
D)  amplitude of brightness variation and luminosity. 
A)  variation of spectral color and distance to the star. 
B)  period of brightness variation and spectral color. 
C)  period of brightness variation and luminosity. 
D)  amplitude of brightness variation and luminosity.

Question 17

In the eighteenth century,Sir William Herschel used star counts in regions of the sky along the Milky Way to estimate the position of the center of the Galaxy.He incorrectly concluded that the Sun was close to the Galaxy's center.The reason for this erroneous conclusion was that

Accepted Answer

A)  Herschel counted all stars in each star field,including many that were outside our Galaxy,thus confusing the distribution. 
B)  the redshift of the more distant stars made them invisible to Herschel. 
C)  he had no knowledge of the large quantity of dust between stars,which obscured the more distant regions of the Galaxy. 
D)  he mistook globular clusters for stars,and those are distributed uniformly around the Sun. 
A)  Herschel counted all stars in each star field,including many that were outside our Galaxy,thus confusing the distribution. 
B)  the redshift of the more distant stars made them invisible to Herschel. 
C)  he had no knowledge of the large quantity of dust between stars,which obscured the more distant regions of the Galaxy. 
D)  he mistook globular clusters for stars,and those are distributed uniformly around the Sun.

Question 18

Interstellar matter blocks our view of the disk of our Galaxy

Accepted Answer

A)  not at all at any wavelength. 
B)  more-or-less equally at all wavelengths from radio waves to light waves. 
C)  most at radio wavelengths,where hydrogen absorbs radio waves efficiently,and least at optical wavelengths. 
D)  more at optical wavelengths,less in the infrared,and not at all at radio wavelengths. 
A)  not at all at any wavelength. 
B)  more-or-less equally at all wavelengths from radio waves to light waves. 
C)  most at radio wavelengths,where hydrogen absorbs radio waves efficiently,and least at optical wavelengths. 
D)  more at optical wavelengths,less in the infrared,and not at all at radio wavelengths.

Question 19

All of the stars that have been observed near the supermassive black hole are being ripped apart and pulled into the event horizon to fall into the singularity.

Accepted Answer

A) True 
 B)False

Question 20

The Milky Way is an example of which type of galaxy?

Accepted Answer

A)  Irregular 
B)  Elliptical 
C)  Lenticular (S0) 
D)  Spiral 
A)  Irregular 
B)  Elliptical 
C)  Lenticular (S0) 
D)  Spiral

Only about 10% of the mass of the Galaxy is in the form of visible stars,gas,and dust.

What useful purpose did RR Lyrae stars serve for Harlow Shapley in locating the galactic center?

What is the shape and size of our Galaxy?

The central core of the Galaxy is in the direction of

One proposal for the mysterious dark matter in the Galaxy is that it is made of massive compact halo objects (MACHOs).

The period-luminosity relationship for Cepheid variable stars,relating variability to absolute overall brightness,thereby providing identifiable beacons throughout our local space,was discovered by

What is microlensing?

"Standard candles," which are important for finding distances to remote galaxies,are

Observations from what two parts of the electromagnetic spectrum reveal that the Galaxy has spiral arms.

The dimensions of the disk of our Milky Way Galaxy are

Flocculent spiral galaxies have spiral arms that are broad,fuzzy,chaotic,and poorly defined and grand-design spiral galaxies have thin,graceful,well-defined spiral arms.

The Sun takes about 220 million years to complete one trip around the Galaxy.

What is the evidence that a supermassive black hole exists at the center of our Galaxy?

If the Galaxy were spinning like our solar system,stars closer to the center would

How would astronomers,ancient or modern,use a "standard candle"?

The significant feature of a Cepheid variable is that there is a relationship between two intrinsic parameters,the first being easily measured,the second being the parameter that is required.These parameters are

In the eighteenth century,Sir William Herschel used star counts in regions of the sky along the Milky Way to estimate the position of the center of the Galaxy.He incorrectly concluded that the Sun was close to the Galaxy's center.The reason for this erroneous conclusion was that

Interstellar matter blocks our view of the disk of our Galaxy

All of the stars that have been observed near the supermassive black hole are being ripped apart and pulled into the event horizon to fall into the singularity.

The Milky Way is an example of which type of galaxy?

Predicting the Motions of the Stars, Sun, and Moon

Decoding the Hidden Messages in Starlight

Analyzing Scales and Motions of the Universe

Exploring Our Evolving Solar System

Uncovering Earths Systems

Exploring Terrestrial Surface Processes and Atmospheres

Observing the Dynamic Giant Planets

Looking for Life Beyond Earth

Probing the Dynamic Sun

Observing Properties of Distant Stars

Inferring Patterns in Star Life Cycles

Predicting the Violent End of the Largest Stars

Investigating Other Galaxies

Observing the Evolution of the Universe

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Exam 13: Exploring Our Galaxy

Only about 10% of the mass of the Galaxy is in the form of visible stars,gas,and dust.

What useful purpose did RR Lyrae stars serve for Harlow Shapley in locating the galactic center?

What is the shape and size of our Galaxy?

The central core of the Galaxy is in the direction of

One proposal for the mysterious dark matter in the Galaxy is that it is made of massive compact halo objects (MACHOs).

The period-luminosity relationship for Cepheid variable stars,relating variability to absolute overall brightness,thereby providing identifiable beacons throughout our local space,was discovered by

What is microlensing?

"Standard candles," which are important for finding distances to remote galaxies,are

Observations from what two parts of the electromagnetic spectrum reveal that the Galaxy has spiral arms.

The dimensions of the disk of our Milky Way Galaxy are

Flocculent spiral galaxies have spiral arms that are broad,fuzzy,chaotic,and poorly defined and grand-design spiral galaxies have thin,graceful,well-defined spiral arms.

The Sun takes about 220 million years to complete one trip around the Galaxy.

What is the evidence that a supermassive black hole exists at the center of our Galaxy?

If the Galaxy were spinning like our solar system,stars closer to the center would

How would astronomers,ancient or modern,use a "standard candle"?

The significant feature of a Cepheid variable is that there is a relationship between two intrinsic parameters,the first being easily measured,the second being the parameter that is required.These parameters are

In the eighteenth century,Sir William Herschel used star counts in regions of the sky along the Milky Way to estimate the position of the center of the Galaxy.He incorrectly concluded that the Sun was close to the Galaxy's center.The reason for this erroneous conclusion was that

Interstellar matter blocks our view of the disk of our Galaxy

All of the stars that have been observed near the supermassive black hole are being ripped apart and pulled into the event horizon to fall into the singularity.

The Milky Way is an example of which type of galaxy?

Predicting the Motions of the Stars, Sun, and Moon

Decoding the Hidden Messages in Starlight

Analyzing Scales and Motions of the Universe

Exploring Our Evolving Solar System

Uncovering Earths Systems

Exploring Terrestrial Surface Processes and Atmospheres

Observing the Dynamic Giant Planets

Looking for Life Beyond Earth

Probing the Dynamic Sun

Observing Properties of Distant Stars

Inferring Patterns in Star Life Cycles

Predicting the Violent End of the Largest Stars

Investigating Other Galaxies

Observing the Evolution of the Universe

Filters