Question 1

What does the technique of interferometry allow?

Accepted Answer

A)  It allows two or more telescopes to obtain a total light-collecting area much larger than the total light-collecting area of the individual telescopes.
B)  It allows two or more telescopes to obtain the angular resolution of a single telescope much larger than any of the individual telescopes.
C)  It allows us to determine the chemical composition of stars.
D)  It allows astronomers to make astronomical observations without interference from light pollution.
E)  It allows the same telescope to make images with both radio waves and visible light.F) A) and B)
G) D) and E)

Question 2

Which of the following is not one of the three main categories of observation generally used by astronomers?

Accepted Answer

A)  filtering to look at just a single color from an object
B)  timing to track how an object's brightness varies with time
C)  spectroscopy to spread an object's light into a spectrum
D)  imaging to get a picture of an astronomical objectsE) B) and C)
F) A) and D)

Question 3

Suppose the two headlights on a car are separated by 1 meter and you are looking at the car from a distance of 2 kilometers.What is the angular separation of the headlights? Can your eyes resolve the two headlights?
(Hint: Recall the angular separation formula α = $ \frac{\mathrm{s}}{2 \pi \mathrm{d}} $ × 360°;the angular resolution of the human eye is about 0.020°. )

Accepted Answer

The separation of the headlights is s = ...

Question 4

The largest effective telescope,created by radio interferometry,is the size of

Accepted Answer

A)  several football fields,in a natural depression in Puerto Rico.
B)  tens of miles across,in the deserts of New Mexico.
C)  the state of New Mexico.
D)  the continental United States.
E)  Earth.F) A) and B)
G) None of the above

Question 5

Which of the following best describes what we mean by the focal plane of a telescope?

Accepted Answer

A)  It is the upper surface of the telescope's primary lens or mirror.
B)  It is the place where,if we mounted film or an electronic detector,we could get a clear (not blurry) image of an object viewed through the telescope.
C)  It is the lower surface of the telescope's primary lens or mirror.
D)  It is the surface of the lens on the eyepiece,through which you would look to see objects in the telescope's field of view.E) A) and D)
F) A) and C)

Question 6

Which of the following effects is caused by atmospheric turbulence?

Accepted Answer

A)  twinkling of stars
B)  light pollution
C)  magnification of images
D)  diffraction of lightE) All of the above
F) C) and D)

Question 7

The angular resolution of a telescope is never less than its diffraction limit.

Accepted Answer

A) True 
 B)False

Question 8

Which of the following best describes the principle advantage of CCDs over photographic film?

Accepted Answer

A)  CCDs allow long exposures (e.g. ,minutes or hours) and film does not.
B)  CCDs capture a much higher percentage of the incoming photons than film.
C)  CCDs can record the colors of astronomical objects accurately while film cannot.
D)  CCDs can be attached to modern telescopes more easily than can photographic film.E) None of the above
F) C) and D)

Question 9

What causes stars to twinkle?

Accepted Answer

A)  It is intrinsic to the stars-their brightness varies as they expand and contract.
B)  variations in the absorption of the atmosphere
C)  variable absorption by interstellar gas along the line of sight to the star
D)  bending of light rays by turbulent layers in the atmosphere
E)  the inability of the human eye to see faint objectsF) All of the above
G) C) and D)

Question 10

Which of the following statements best describes the two principal advantages of telescopes over eyes?

Accepted Answer

A)  Telescopes can collect far more light with far better angular resolution.
B)  Telescopes can collect far more light with far greater magnification.
C)  Telescopes have much more magnification and better angular resolution.
D)  Telescopes collect more light and are unaffected by twinkling.
E)  Telescopes can see farther without image distortion and can record more accurate colors.F) A) and C)
G) A) and B)

Question 11

Which of the following studies is best suited to astronomical observations that fall into the category called timing?

Accepted Answer

A)  studying how different planets differ in their surface compositions
B)  studying how a star's brightness varies over a period of 3 years
C)  measuring the rotation rate of a distant star
D)  determining the age of the solar systemE) All of the above
F) A) and D)

Question 12

What is spectral resolution? Why can a large telescope allow for a higher spectral resolution than a smaller telescope?

Accepted Answer

Spectral resolution is a measure of the ...

Question 13

The diffraction-limited resolution of a 10-meter telescope is about 0.01 arcsecond for visible light.Would you expect the actual angular resolution of a Keck 10-meter telescope in Hawaii to be better than,equal to,or worse than 0.01 arcsecond? Explain.

Accepted Answer

It would be worse th...

Question 14

Suppose the angular separation of two stars is smaller than the angular resolution of your eyes.How will the stars appear to your eyes?

Accepted Answer

A)  You will not be able to see these two stars at all.
B)  The two stars will look like a single point of light.
C)  The two stars will appear to be touching,looking rather like a small dumbbell.
D)  You will see two distinct stars.
E)  You will see only the larger of the two stars,not the smaller one.F) None of the above
G) C) and D)

Question 15

Suppose you point your telescope at a distant object.Which of the following is not an advantage of taking a photograph of the object through the telescope as compared to just looking at the object through the telescope?

Accepted Answer

A)  The photograph will have far better angular resolution than you can see with your eye.
B)  By using a long exposure time,the photograph can allow you to see objects that would be too dim to see with your eye.
C)  If taken with a camera with a sensitive detector such as a CCD,the photograph can capture a much larger percentage of the incoming photons than can your eye.
D)  The photograph provides a more reliable record of what is seen through the telescope than can a drawing made by eye.E) None of the above
F) All of the above

Question 16

What does angular resolution measure?

Accepted Answer

A)  the angular size of the smallest features that the telescope can see
B)  the brightness of an image
C)  the size of an image
D)  the number of electromagnetic waves captured by an imageE) All of the above
F) A) and B)

Question 17

Most astronomical objects emit light over a broad range of wavelengths.

Accepted Answer

A) True 
 B)False

Question 18

What is the purpose of interferometry?

Accepted Answer

A)  It allows two or more small telescopes to achieve the angular resolution of a much larger telescope.
B)  It allows two or more small telescopes to achieve a larger light-collecting area than they would have independently.
C)  It is designed to prevent light pollution from interfering with astronomical observations.
D)  It reduces the twinkling of stars caused by atmospheric turbulence.E) A) and D)
F) B) and C)

Question 19

Which of the following studies is best suited to a time monitoring experiment?

Accepted Answer

A)  studying how different stars differ in their chemical compositions
B)  studying whether a particular star's brightness is steady or variable
C)  determining the age of the solar system
D)  measuring the rotation rate of a distant star
E)  estimating the time since the Big BangF) All of the above
G) B) and C)

Question 20

The Hubble Space Telescope is famous because,at least at the time of its launch,it was the largest visible light telescope ever built.

Accepted Answer

A) True 
 B)False

Exam 6: Telescopes: Portals of Discovery

Which of the following studies is best suited to astronomical observations that fall into the category called timing?

Correct Answer
verified

Which of the following best describes what we mean by the focal plane of a telescope?

Correct Answer
verified

Most astronomical objects emit light over a broad range of wavelengths.

Correct Answer
verified

The Hubble Space Telescope is famous because,at least at the time of its launch,it was the largest visible light telescope ever built.

Correct Answer
verified

The diffraction-limited resolution of a 10-meter telescope is about 0.01 arcsecond for visible light.Would you expect the actual angular resolution of a Keck 10-meter telescope in Hawaii to be better than,equal to,or worse than 0.01 arcsecond? Explain.

Correct Answer
verified
It would be worse th...
View Answer

What is spectral resolution? Why can a large telescope allow for a higher spectral resolution than a smaller telescope?

Correct Answer
verified
Spectral resolution is a measure of the ...
View Answer

Suppose the angular separation of two stars is smaller than the angular resolution of your eyes.How will the stars appear to your eyes?

Correct Answer
verified

The angular resolution of a telescope is never less than its diffraction limit.

Correct Answer
verified

Which of the following effects is caused by atmospheric turbulence?

Correct Answer
verified

Which of the following is not one of the three main categories of observation generally used by astronomers?

Correct Answer
verified

Which of the following studies is best suited to a time monitoring experiment?

Correct Answer
verified

Correct Answer
verified
The separation of the headlights is s = ...
View Answer

Suppose you point your telescope at a distant object.Which of the following is not an advantage of taking a photograph of the object through the telescope as compared to just looking at the object through the telescope?

Correct Answer
verified

What causes stars to twinkle?

Correct Answer
verified

Which of the following statements best describes the two principal advantages of telescopes over eyes?

Correct Answer
verified

What does angular resolution measure?

Correct Answer
verified

Which of the following best describes the principle advantage of CCDs over photographic film?

Correct Answer
verified

The largest effective telescope,created by radio interferometry,is the size of

Correct Answer
verified

What does the technique of interferometry allow?

Correct Answer
verified

What is the purpose of interferometry?

Correct Answer
verified

Exam 6: Telescopes: Portals of Discovery

Which of the following studies is best suited to astronomical observations that fall into the category called timing?

Correct AnswerverifiedShow Answer

Which of the following best describes what we mean by the focal plane of a telescope?

Correct AnswerverifiedShow Answer

Most astronomical objects emit light over a broad range of wavelengths.

Correct AnswerverifiedShow Answer

The Hubble Space Telescope is famous because,at least at the time of its launch,it was the largest visible light telescope ever built.

Correct AnswerverifiedShow Answer

The diffraction-limited resolution of a 10-meter telescope is about 0.01 arcsecond for visible light.Would you expect the actual angular resolution of a Keck 10-meter telescope in Hawaii to be better than,equal to,or worse than 0.01 arcsecond? Explain.

Correct AnswerverifiedIt would be worse th...View AnswerShow Answer

What is spectral resolution? Why can a large telescope allow for a higher spectral resolution than a smaller telescope?

Correct AnswerverifiedSpectral resolution is a measure of the ...View AnswerShow Answer

Suppose the angular separation of two stars is smaller than the angular resolution of your eyes.How will the stars appear to your eyes?

Correct AnswerverifiedShow Answer

The angular resolution of a telescope is never less than its diffraction limit.

Correct AnswerverifiedShow Answer

Which of the following effects is caused by atmospheric turbulence?

Correct AnswerverifiedShow Answer

Which of the following is not one of the three main categories of observation generally used by astronomers?

Correct AnswerverifiedShow Answer

Which of the following studies is best suited to a time monitoring experiment?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedThe separation of the headlights is s = ...View AnswerShow Answer

Suppose you point your telescope at a distant object.Which of the following is not an advantage of taking a photograph of the object through the telescope as compared to just looking at the object through the telescope?

Correct AnswerverifiedShow Answer

What causes stars to twinkle?

Correct AnswerverifiedShow Answer

Which of the following statements best describes the two principal advantages of telescopes over eyes?

Correct AnswerverifiedShow Answer

What does angular resolution measure?

Correct AnswerverifiedShow Answer

Which of the following best describes the principle advantage of CCDs over photographic film?

Correct AnswerverifiedShow Answer

The largest effective telescope,created by radio interferometry,is the size of

Correct AnswerverifiedShow Answer

What does the technique of interferometry allow?

Correct AnswerverifiedShow Answer

What is the purpose of interferometry?

Correct AnswerverifiedShow Answer

Correct Answer
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Correct Answer
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Correct Answer
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verified
It would be worse th...
View Answer

Correct Answer
verified
Spectral resolution is a measure of the ...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
The separation of the headlights is s = ...
View Answer

Correct Answer
verified

Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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