Question 1

A star of the Sun's diameter,but twice as hot,must be 16X more luminous than the Sun.

Accepted Answer

A) True 
 B)False

Question 2

The proper motion of a star is its true velocity through space.

Accepted Answer

A) True 
 B)False

Question 3

For a star of 10 solar masses,its main sequence life span will be:

Accepted Answer

A)  ten times longer than our Sun's. 
B)  about the same as the Sun's. 
C)  only a tenth of the Sun's. 
D)  about a hundred times less than the Sun's. 
E)  only 1/1000th of the Sun. 
A)  ten times longer than our Sun's. 
B)  about the same as the Sun's. 
C)  only a tenth of the Sun's. 
D)  about a hundred times less than the Sun's. 
E)  only 1/1000th of the Sun.

Question 4

In a spectroscopic binary,the star whose lines shift the most weighs the most.

Accepted Answer

A) True 
 B)False

Question 5

At the distance of Jupiter (6 times further away from the Sun than Earth)the amount of sunlight received per square centimeter different by what factor?

Accepted Answer

A)  6 times less 
B)  12 times less 
C)  36 times less 
D)  6 times more 
E)  12 times more 
A)  6 times less 
B)  12 times less 
C)  36 times less 
D)  6 times more 
E)  12 times more

Question 6

If a star is found by spectroscopic observations to be about 500 parsecs distant,its parallax is:

Accepted Answer

A)  0.2". 
B)  0.5". 
C)  0.02". 
D)  0.002". 
E)  0.005". 
A)  0.2". 
B)  0.5". 
C)  0.02". 
D)  0.002". 
E)  0.005".

Question 7

The ESA's GAIA project will be able to measure parallax and stellar properties of about how many stars?

Accepted Answer

A)  one million 
B)  ten thousand 
C)  one billion 
D)  one hundred billion 
E)  None; it has a different purpose. 
A)  one million 
B)  ten thousand 
C)  one billion 
D)  one hundred billion 
E)  None; it has a different purpose.

Question 8

Why must both parallax and proper motion be known to give transverse velocity?

Accepted Answer

To turn the star's apparent mo

Question 9

Why are spectra of stars different?

Accepted Answer

Spectra of stars differ primarily becaus

Question 10

Perhaps the greatest of the Greek astronomers,________ compiled the first catalog of stars,accurately measured their positions,and defined the basic system of stellar brightnesses.

Accepted Answer

A)  Erastothenes 
B)  Aristotle 
C)  Ptolemy 
D)  Hipparchus 
E)  Aristarchus 
A)  Erastothenes 
B)  Aristotle 
C)  Ptolemy 
D)  Hipparchus 
E)  Aristarchus

Question 11

The star's color index is a quick way of determining its:

Accepted Answer

A)  density. 
B)  luminosity. 
C)  mass. 
D)  temperature. 
E)  composition. 
A)  density. 
B)  luminosity. 
C)  mass. 
D)  temperature. 
E)  composition.

Question 12

A star of ten solar masses would probably stay stable on the main sequence only about 1/1000th as long as our Sun.

Accepted Answer

A) True 
 B)False

Question 13

The absolute magnitude of a star is its brightness as seen from a distance of:

Accepted Answer

A)  one million kilometers. 
B)  one astronomical unit. 
C)  one light year. 
D)  ten parsecs. 
E)  10 light years. 
A)  one million kilometers. 
B)  one astronomical unit. 
C)  one light year. 
D)  ten parsecs. 
E)  10 light years.

Question 14

What types of observations are necessary to determine the absolute luminosity of a star?

Accepted Answer

The absolute luminosity of a star,or abs

Question 15

What is proper motion?

Accepted Answer

A)  It is the true, not apparent, motion of a star in space. 
B)  It is the apparent shift as we go to opposite sides of our orbit every six months. 
C)  It is the annual apparent motion of a star across the sky. 
D)  It is the motion of a star towards or away from us, revealed by Doppler shifts. 
E)  It is the orbital motion of a star around the Galaxy. 
A)  It is the true, not apparent, motion of a star in space. 
B)  It is the apparent shift as we go to opposite sides of our orbit every six months. 
C)  It is the annual apparent motion of a star across the sky. 
D)  It is the motion of a star towards or away from us, revealed by Doppler shifts. 
E)  It is the orbital motion of a star around the Galaxy.

Question 16

Upon what data do measurements of sizes of eclipsing binaries depend?

Accepted Answer

A)  their orbital periods and separations 
B)  their masses and luminosities 
C)  their Doppler shifts and durations of stages of their eclipses 
D)  their temperatures and speeds 
E)  their temperatures and masses 
A)  their orbital periods and separations 
B)  their masses and luminosities 
C)  their Doppler shifts and durations of stages of their eclipses 
D)  their temperatures and speeds 
E)  their temperatures and masses

Question 17

On the H-R diagram,red supergiants like Betelguese lie:

Accepted Answer

A)  at the bottom left. 
B)  at the bottom right. 
C)  at the top left. 
D)  at the top right. 
E)  They can't be plotted, for they are not main sequence. 
A)  at the bottom left. 
B)  at the bottom right. 
C)  at the top left. 
D)  at the top right. 
E)  They can't be plotted, for they are not main sequence.

Question 18

Which type of binary can have their sizes measured directly by photometry?

Accepted Answer

A)  virtual 
B)  visual 
C)  eclipsing 
D)  spectroscopic 
E)  astrometric 
A)  virtual 
B)  visual 
C)  eclipsing 
D)  spectroscopic 
E)  astrometric

Question 19

Which of the following best describes the size and distance relationship of our Sun and the nearest star?

Accepted Answer

A)  a tennis ball here, another on the Moon 
B)  two beach balls separated by 100 city blocks 
C)  two grains of sand separated by 100 light years 
D)  two marbles separated by 300 kilometers 
E)  two baseballs separated by 100 yards 
A)  a tennis ball here, another on the Moon 
B)  two beach balls separated by 100 city blocks 
C)  two grains of sand separated by 100 light years 
D)  two marbles separated by 300 kilometers 
E)  two baseballs separated by 100 yards

Question 20

Star A has an absolute magnitude of 2.5 and star B has an apparent magnitude of 2.5,but star A is a main sequence star and star B is a red giant.Which statement below is correct?

Accepted Answer

A)  Star A appears brighter than star B, but actually star B and star A are the same brightness. 
B)  Star B appears brighter than star A, but actually star B and star A are the same brightness. 
C)  Star A and star B appear to have the same brightness, but actually star B is brighter than star A. 
D)  Star A and star B appear to have the same brightness, but actually star A is brighter than star B. 
E)  It is impossible to determine how bright these stars are or appear to be relative to one another, given the information above. 
A)  Star A appears brighter than star B, but actually star B and star A are the same brightness. 
B)  Star B appears brighter than star A, but actually star B and star A are the same brightness. 
C)  Star A and star B appear to have the same brightness, but actually star B is brighter than star A. 
D)  Star A and star B appear to have the same brightness, but actually star A is brighter than star B. 
E)  It is impossible to determine how bright these stars are or appear to be relative to one another, given the information above.

Exam 17: The Stars: Giants,Dwarfs,and the Main Sequence

A star of the Sun's diameter,but twice as hot,must be 16X more luminous than the Sun.

The proper motion of a star is its true velocity through space.

For a star of 10 solar masses,its main sequence life span will be:

In a spectroscopic binary,the star whose lines shift the most weighs the most.

At the distance of Jupiter (6 times further away from the Sun than Earth)the amount of sunlight received per square centimeter different by what factor?

If a star is found by spectroscopic observations to be about 500 parsecs distant,its parallax is:

The ESA's GAIA project will be able to measure parallax and stellar properties of about how many stars?

Why must both parallax and proper motion be known to give transverse velocity?

Why are spectra of stars different?

Perhaps the greatest of the Greek astronomers,________ compiled the first catalog of stars,accurately measured their positions,and defined the basic system of stellar brightnesses.

The star's color index is a quick way of determining its:

A star of ten solar masses would probably stay stable on the main sequence only about 1/1000th as long as our Sun.

The absolute magnitude of a star is its brightness as seen from a distance of:

What types of observations are necessary to determine the absolute luminosity of a star?

What is proper motion?

Upon what data do measurements of sizes of eclipsing binaries depend?

On the H-R diagram,red supergiants like Betelguese lie:

Which type of binary can have their sizes measured directly by photometry?

Which of the following best describes the size and distance relationship of our Sun and the nearest star?

Star A has an absolute magnitude of 2.5 and star B has an apparent magnitude of 2.5,but star A is a main sequence star and star B is a red giant.Which statement below is correct?

Charting the Heavens: The Foundations of Astronomy

The Copernican Revolution: The Birth of Modern Science

Radiation: Information from the Cosmos

Spectroscopy: The Inner Workings of Atoms

Telescopes: The Tools of Astronomy

The Solar System: Comparative Planetology and Formation Models

Earth: Our Home in Space

The Moon and Mercury: Scorched and Battered Worlds

Venus: Earth's Sister Planet

Mars: A Near Miss for Life?

Jupiter: Giant of the Solar System

Saturn: Spectacular Rings and Mysterious Moons

Uranus and Neptune: The Outer Worlds of the Solar System

Solar System Debris: Keys to Our Origin

Exoplanets: Planetary Systems Beyond Our Own

The Sun: Our Parent Star

The Interstellar Medium: Gas and Dust among the Stars

Star Formation: A Traumatic Birth

Stellar Evolution: The Life and Death of a Star

Stellar Explosions: Novae,Supernovae,and the Formation of the Elements

Neutron Stars and Black Holes: Strange States of Matter

The Milky Way Galaxy: A Spiral in Space

Galaxies: Building Blocks of the Universe

Galaxies and Dark Matter: The Large-Scale Structure of the Cosmos

Cosmology: The Big Bang and the Fate of the Universe

The Early Universe: Toward the Beginning of Time

Life in the Universe: Are We Alone?

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