Question 1

How far away is the nearest star beyond the Sun?

Accepted Answer

A)  about 1/4 ly away 
B)  about 1/10 ly away 
C)  about 4 ly away 
D)  between 1 and 2 ly away 
A)  about 1/4 ly away 
B)  about 1/10 ly away 
C)  about 4 ly away 
D)  between 1 and 2 ly away

Question 2

How can we tell that some stars are relatively close to Earth in the sky?

Accepted Answer

A)  The stars appear to move periodically back and forth against the background stars because of Earth's movement around the Sun. 
B)  The stars appear to be extremely bright and must therefore be very close to us. 
C)  The stars are occasionally occulted or eclipsed by the Moon; hence, they must be close. 
D)  The light from these stars shows only a very small redshift caused by the universal expansion of the universe, so they must be close. 
A)  The stars appear to move periodically back and forth against the background stars because of Earth's movement around the Sun. 
B)  The stars appear to be extremely bright and must therefore be very close to us. 
C)  The stars are occasionally occulted or eclipsed by the Moon; hence, they must be close. 
D)  The light from these stars shows only a very small redshift caused by the universal expansion of the universe, so they must be close.

Question 3

The modern system of apparent magnitudes uses the star Vega as its basis.In this scheme,Vega is defined to have an apparent magnitude of:

Accepted Answer

A)  10. 
B)  1.0. 
C)  0.0. 
D)  -1.0. 
A)  10. 
B)  1.0. 
C)  0.0. 
D)  -1.0.

Question 4

Where on the Hertzsprung-Russell diagram do most local stars in our universe congregate?

Accepted Answer

A)  the white dwarf area, the "graveyard" of stars 
B)  the supergiant area, where the most massive stars spend a significant time 
C)  the giant area, where most stars spend the longest time of their lives 
D)  the main sequence, where stars are generating energy by fusion reactions 
A)  the white dwarf area, the "graveyard" of stars 
B)  the supergiant area, where the most massive stars spend a significant time 
C)  the giant area, where most stars spend the longest time of their lives 
D)  the main sequence, where stars are generating energy by fusion reactions

Question 5

Two stars,one classified A4 V and the other A4 III,have the same apparent magnitude.There is no significant amount of absorption of starlight by interstellar material.From this information we know that the A4 V star is _____ than the A4 III star.

Accepted Answer

A)  cooler 
B)  closer to the Sun 
C)  farther from the Sun 
D)  Hotter 
A)  cooler 
B)  closer to the Sun 
C)  farther from the Sun 
D)  Hotter

Question 6

Rigel,the bright star in the knee of Orion,has a surface temperature of about 12,000 K.Through which filter will it appear brightest? (See Figure 10-4,Comins,Discovering the Essential Universe,6th ed.)

Accepted Answer

A)  ultraviolet 
B)  blue 
C)  yellow 
D)  red 
A)  ultraviolet 
B)  blue 
C)  yellow 
D)  red

Question 7

Three stars have the following apparent (m)and absolute (M)magnitudes: Star A: M = 1.8 m = 3.8
Star B: M = 2.5 m = 9.5
Star C: M = 7.6 m = 15.1
Which star is closest?

Accepted Answer

A)  Star A 
B)  Star B 
C)  Star C 
D)  cannot be determined from these data 
A)  Star A 
B)  Star B 
C)  Star C 
D)  cannot be determined from these data

Question 8

If the surface temperatures of white dwarf stars are 4 times that of the Sun,and energy output per unit area of a star depends on the fourth power of the temperature by the Stefan-Boltzmann relation,why are white dwarfs intrinsically so faint?

Accepted Answer

A)  White dwarfs are very small. 
B)  White dwarfs have very thin atmospheres that do not emit continuum radiation but only line emissions, like a low-density gas. 
C)  White dwarfs are shrouded in very thick atmospheres. 
D)  White dwarfs are moving rapidly away from the Sun and their spectra are extremely redshifted, hence they appear faint at visible wavelengths. 
A)  White dwarfs are very small. 
B)  White dwarfs have very thin atmospheres that do not emit continuum radiation but only line emissions, like a low-density gas. 
C)  White dwarfs are shrouded in very thick atmospheres. 
D)  White dwarfs are moving rapidly away from the Sun and their spectra are extremely redshifted, hence they appear faint at visible wavelengths.

Question 9

What would be the mass of a main-sequence star that has a luminosity 1000 times greater than that of the Sun? (See Figure 10-15,Comins,Discovering the Essential Universe,6th ed.)

Accepted Answer

A)  10⁵ solar masses 
B)  5 solar masses 
C)  0.1 solar mass 
D)  1000 solar masses 
A)  10⁵ solar masses 
B)  5 solar masses 
C)  0.1 solar mass 
D)  1000 solar masses

Question 10

The spectral class of the star Enif is K2,while that of the Sun is G2.Which conclusion can be drawn about Enif from this information?

Accepted Answer

A)  Enif is intrinsically fainter than the Sun. 
B)  Enif is intrinsically brighter than the Sun. 
C)  Enif is cooler than the Sun. 
D)  Enif is hotter than the Sun. 
A)  Enif is intrinsically fainter than the Sun. 
B)  Enif is intrinsically brighter than the Sun. 
C)  Enif is cooler than the Sun. 
D)  Enif is hotter than the Sun.

Question 11

The star Rigel,in the constellation Orion,appears brighter through a blue filter than it does through a yellow filter.Suppose that a second star is found that has the same brightness as Rigel through the yellow filter but is brighter than Rigel through the blue filter.From this information,we can say conclusively that the second star has:

Accepted Answer

A)  the same temperature but a lower luminosity. 
B)  a higher temperature. 
C)  a lower temperature. 
D)  the same temperature but a higher luminosity. 
A)  the same temperature but a lower luminosity. 
B)  a higher temperature. 
C)  a lower temperature. 
D)  the same temperature but a higher luminosity.

Question 12

Which two fundamental parameters are MOST often used to place a particular star on a path of stellar evolution for comparison with theoretical models?

Accepted Answer

A)  apparent magnitude and distance 
B)  apparent magnitude and temperature 
C)  luminosity, or total energy output, and distance 
D)  luminosity, or total energy output, and temperature 
A)  apparent magnitude and distance 
B)  apparent magnitude and temperature 
C)  luminosity, or total energy output, and distance 
D)  luminosity, or total energy output, and temperature

Question 13

A particular star is at a distance of 5 pc from Earth.For this star,the apparent magnitude will have:

Accepted Answer

A)  the same value as its absolute magnitude since magnitude is independent of distance. 
B)  a smaller value than its absolute magnitude. 
C)  a larger or smaller value than its absolute magnitude, depending on the temperature and diameter of the star. 
D)  a larger value than its absolute magnitude. 
A)  the same value as its absolute magnitude since magnitude is independent of distance. 
B)  a smaller value than its absolute magnitude. 
C)  a larger or smaller value than its absolute magnitude, depending on the temperature and diameter of the star. 
D)  a larger value than its absolute magnitude.

Question 14

The surface temperature of a nearby star can be determined most precisely by measuring what parameters?

Accepted Answer

A)  the position of the star on the H-R diagram 
B)  the Doppler shift of the star's spectral lines 
C)  the relative strengths of emission lines from different atoms and ions in the star's spectrum 
D)  the relative strengths of absorption lines from different atoms (e.g., H, Ca) and molecules (e.g., TiO) in the star's spectrum 
A)  the position of the star on the H-R diagram 
B)  the Doppler shift of the star's spectral lines 
C)  the relative strengths of emission lines from different atoms and ions in the star's spectrum 
D)  the relative strengths of absorption lines from different atoms (e.g., H, Ca) and molecules (e.g., TiO) in the star's spectrum

Question 15

The star Hadar is classified as B1 II,which means that it is a:

Accepted Answer

A)  cool supergiant. 
B)  hot, bright giant. 
C)  cool giant. 
D)  hot supergiant. 
A)  cool supergiant. 
B)  hot, bright giant. 
C)  cool giant. 
D)  hot supergiant.

Question 16

In the spectral classification scheme,what designation is given to a star just a little hotter than an F8 star?

Accepted Answer

A)  F7 
B)  F9 
C)  G8 
D)  A8 
A)  F7 
B)  F9 
C)  G8 
D)  A8

Question 17

According to the mass-luminosity relation shown in Figure 10-14 of Comins,Discovering the Essential Universe,6th ed.,what is the mass of the star Regulus (α Leonis,the brightest star in the constellation Leo)? See also the Hertzsprung-Russell diagram in Figure 10-7.

Accepted Answer

A)  between 2.5 and 5 solar masses 
B)  between 1.5 and 2 solar masses 
C)  between 10 and 15 solar masses 
D)  between 8 and 10 solar masses 
A)  between 2.5 and 5 solar masses 
B)  between 1.5 and 2 solar masses 
C)  between 10 and 15 solar masses 
D)  between 8 and 10 solar masses

Question 18

We are about 8000 parsecs from the center of the Milky Way Galaxy,and the smallest parallax angle we can measure from orbiting observatories is about 0.001 arcseconds.How far toward the galactic center can we see with this technique (ignoring galactic dust and other obstacles)?

Accepted Answer

A)  all the way to the center 
B)  about halfway to the center 
C)  about 1/8 of the way to the center 
D)  only 0.008 = 1/125 of the way to the center 
A)  all the way to the center 
B)  about halfway to the center 
C)  about 1/8 of the way to the center 
D)  only 0.008 = 1/125 of the way to the center

Question 19

How do astronomers measure the masses of stars?

Accepted Answer

A)  by observing the star's brightness at different wavelengths (colors) 
B)  by observing the motion of two stars in a binary star system 
C)  by measuring the star's brightness, temperature, and distance 
D)  by measuring the star's brightness and obtaining its radius using the H-R diagram 
A)  by observing the star's brightness at different wavelengths (colors) 
B)  by observing the motion of two stars in a binary star system 
C)  by measuring the star's brightness, temperature, and distance 
D)  by measuring the star's brightness and obtaining its radius using the H-R diagram

Question 20

Why does the star Bellatrix in Orion looks bluish to the naked eye?

Accepted Answer

A)  The spectrum of light emitted from Bellatrix peaks in the blue region of the spectrum, and in fact, almost all its light is concentrated in the blue region of the spectrum. 
B)  The spectrum of light emitted from Bellatrix peaks in the ultraviolet region of the spectrum. Within the visible part of the spectrum, there is more emission in the blue than in any other color. 
C)  Bellatrix is moving toward Earth rapidly enough that its light appears appreciably blueshifted. 
D)  Bellatrix is made of blue material. 
A)  The spectrum of light emitted from Bellatrix peaks in the blue region of the spectrum, and in fact, almost all its light is concentrated in the blue region of the spectrum. 
B)  The spectrum of light emitted from Bellatrix peaks in the ultraviolet region of the spectrum. Within the visible part of the spectrum, there is more emission in the blue than in any other color. 
C)  Bellatrix is moving toward Earth rapidly enough that its light appears appreciably blueshifted. 
D)  Bellatrix is made of blue material.

How far away is the nearest star beyond the Sun?

How can we tell that some stars are relatively close to Earth in the sky?

The modern system of apparent magnitudes uses the star Vega as its basis.In this scheme,Vega is defined to have an apparent magnitude of:

Where on the Hertzsprung-Russell diagram do most local stars in our universe congregate?

Two stars,one classified A4 V and the other A4 III,have the same apparent magnitude.There is no significant amount of absorption of starlight by interstellar material.From this information we know that the A4 V star is _____ than the A4 III star.

Rigel,the bright star in the knee of Orion,has a surface temperature of about 12,000 K.Through which filter will it appear brightest? (See Figure 10-4,Comins,Discovering the Essential Universe,6th ed.)

Three stars have the following apparent (m)and absolute (M)magnitudes: Star A: M = 1.8 m = 3.8 Star B: M = 2.5 m = 9.5 Star C: M = 7.6 m = 15.1 Which star is closest?

If the surface temperatures of white dwarf stars are 4 times that of the Sun,and energy output per unit area of a star depends on the fourth power of the temperature by the Stefan-Boltzmann relation,why are white dwarfs intrinsically so faint?

What would be the mass of a main-sequence star that has a luminosity 1000 times greater than that of the Sun? (See Figure 10-15,Comins,Discovering the Essential Universe,6th ed.)

The spectral class of the star Enif is K2,while that of the Sun is G2.Which conclusion can be drawn about Enif from this information?

Which two fundamental parameters are MOST often used to place a particular star on a path of stellar evolution for comparison with theoretical models?

A particular star is at a distance of 5 pc from Earth.For this star,the apparent magnitude will have:

The surface temperature of a nearby star can be determined most precisely by measuring what parameters?

The star Hadar is classified as B1 II,which means that it is a:

In the spectral classification scheme,what designation is given to a star just a little hotter than an F8 star?

According to the mass-luminosity relation shown in Figure 10-14 of Comins,Discovering the Essential Universe,6th ed.,what is the mass of the star Regulus (α Leonis,the brightest star in the constellation Leo)? See also the Hertzsprung-Russell diagram in Figure 10-7.

We are about 8000 parsecs from the center of the Milky Way Galaxy,and the smallest parallax angle we can measure from orbiting observatories is about 0.001 arcseconds.How far toward the galactic center can we see with this technique (ignoring galactic dust and other obstacles)?

How do astronomers measure the masses of stars?

Why does the star Bellatrix in Orion looks bluish to the naked eye?

Discovering the Night Sky

Gravitation and the Waltz of the Planets

Light and Telescopes

Formation of the Solar System and Other Planetary Systems

Exoplanets

The Terrestrial Planets and Their Moons

The Outer Planets and Their Moons

Vagabonds of the Solar System

The Sun: Our Extraordinary Ordinary Star

The Lives of the Stars From Birth Through Middle Age

The Deaths and Remnants of Stars

The Galaxies

Cosmology

Astrobiology

Filters

Exam 10: Characterizing Stars

How far away is the nearest star beyond the Sun?

How can we tell that some stars are relatively close to Earth in the sky?

The modern system of apparent magnitudes uses the star Vega as its basis.In this scheme,Vega is defined to have an apparent magnitude of:

Where on the Hertzsprung-Russell diagram do most local stars in our universe congregate?

Two stars,one classified A4 V and the other A4 III,have the same apparent magnitude.There is no significant amount of absorption of starlight by interstellar material.From this information we know that the A4 V star is _____ than the A4 III star.

Rigel,the bright star in the knee of Orion,has a surface temperature of about 12,000 K.Through which filter will it appear brightest? (See Figure 10-4,Comins,Discovering the Essential Universe,6th ed.)

Three stars have the following apparent (m)and absolute (M)magnitudes: Star A: M = 1.8 m = 3.8 Star B: M = 2.5 m = 9.5 Star C: M = 7.6 m = 15.1 Which star is closest?

If the surface temperatures of white dwarf stars are 4 times that of the Sun,and energy output per unit area of a star depends on the fourth power of the temperature by the Stefan-Boltzmann relation,why are white dwarfs intrinsically so faint?

What would be the mass of a main-sequence star that has a luminosity 1000 times greater than that of the Sun? (See Figure 10-15,Comins,Discovering the Essential Universe,6th ed.)

The spectral class of the star Enif is K2,while that of the Sun is G2.Which conclusion can be drawn about Enif from this information?

Which two fundamental parameters are MOST often used to place a particular star on a path of stellar evolution for comparison with theoretical models?

A particular star is at a distance of 5 pc from Earth.For this star,the apparent magnitude will have:

The surface temperature of a nearby star can be determined most precisely by measuring what parameters?

The star Hadar is classified as B1 II,which means that it is a:

In the spectral classification scheme,what designation is given to a star just a little hotter than an F8 star?

According to the mass-luminosity relation shown in Figure 10-14 of Comins,Discovering the Essential Universe,6th ed.,what is the mass of the star Regulus (α Leonis,the brightest star in the constellation Leo)? See also the Hertzsprung-Russell diagram in Figure 10-7.

We are about 8000 parsecs from the center of the Milky Way Galaxy,and the smallest parallax angle we can measure from orbiting observatories is about 0.001 arcseconds.How far toward the galactic center can we see with this technique (ignoring galactic dust and other obstacles)?

How do astronomers measure the masses of stars?

Why does the star Bellatrix in Orion looks bluish to the naked eye?

Discovering the Night Sky

Gravitation and the Waltz of the Planets

Light and Telescopes

Formation of the Solar System and Other Planetary Systems

Exoplanets

The Terrestrial Planets and Their Moons

The Outer Planets and Their Moons

Vagabonds of the Solar System

The Sun: Our Extraordinary Ordinary Star

The Lives of the Stars From Birth Through Middle Age

The Deaths and Remnants of Stars

The Galaxies

Cosmology

Astrobiology

Filters