Question 1

The figure below indicates a possible picture of a theoretical universe with two separate observers within it.Which of the following statements describes this universe?

Accepted Answer

A)  This universe is homogeneous but not isotropic. 
B)  This universe is isotropic but not homogeneous. 
C)  This universe is both homogeneous and isotropic. 
D)  This universe is neither homogeneous nor isotropic. 
A)  This universe is homogeneous but not isotropic. 
B)  This universe is isotropic but not homogeneous. 
C)  This universe is both homogeneous and isotropic. 
D)  This universe is neither homogeneous nor isotropic.

Question 2

The spectrum of a galaxy is observed to have a hydrogen emission line,normally found at 656.3 nm,with a measured wavelength of 856.3 nm.What is its distance if the Hubble constant is 22 km/s/Mly?

Accepted Answer

z = (λ_obs - λ_rest)/λ_rest = (856.3 nm - 65

Question 3

If the distance of a galaxy is 100 Mly,what is its recessional velocity if the Hubble constant is 22 km/s/Mly?

Accepted Answer

A)  100 km/s 
B)  220 km/s 
C)  1,000 km/s 
D)  2,200 km/s 
A)  100 km/s 
B)  220 km/s 
C)  1,000 km/s 
D)  2,200 km/s

Question 4

If suddenly we find that the distance between Earth and the Sun is now 10 percent larger than we thought it was before,what else will change?

Accepted Answer

A)  The distances of stars 
B)  The size of our galaxy 
C)  The value of H0 
D)  All of the above 
A)  The distances of stars 
B)  The size of our galaxy 
C)  The value of H0 
D)  All of the above

Question 5

Hubble's constant,H0,represents:

Accepted Answer

A)  the rate of expansion of the universe 
B)  the speed at which galaxies are moving away from us 
C)  the time it takes a galaxy to move twice as far away from us 
D)  the size of the universe 
A)  the rate of expansion of the universe 
B)  the speed at which galaxies are moving away from us 
C)  the time it takes a galaxy to move twice as far away from us 
D)  the size of the universe

Question 6

Astronomers use galactic redshift as a measure of:

Accepted Answer

A)  gravity 
B)  distance 
C)  velocity 
D)  mass 
A)  gravity 
B)  distance 
C)  velocity 
D)  mass

Question 7

The existence of the cosmic background radiation tells us that the early universe was:

Accepted Answer

A)  much hotter than it is today 
B)  much colder than it is today 
C)  composed entirely of radiation at early times 
D)  composed entirely of stars at early times 
A)  much hotter than it is today 
B)  much colder than it is today 
C)  composed entirely of radiation at early times 
D)  composed entirely of stars at early times

Question 8

What did Edwin Hubble study in the Andromeda Galaxy that proved it was an individual galaxy and not part of our own Milky Way?

Accepted Answer

A)  Cepheid stars 
B)  Type Ia supernovae 
C)  Globular clusters 
D)  Red Giant stars 
A)  Cepheid stars 
B)  Type Ia supernovae 
C)  Globular clusters 
D)  Red Giant stars

Question 9

Which of the following lists distance indicators that are used to measure distances ranging from the very nearest to the very farthest?

Accepted Answer

A)  Cepheids,parallax,main-sequence fitting,Type Ia supernovae 
B)  Parallax,main-sequence fitting,Cepheids,Type Ia supernovae 
C)  Parallax,main-sequence fitting,Type Ia supernovae,Cepheids 
D)  Main-sequence fitting,parallax,Cepheids,Type Ia supernovae 
A)  Cepheids,parallax,main-sequence fitting,Type Ia supernovae 
B)  Parallax,main-sequence fitting,Cepheids,Type Ia supernovae 
C)  Parallax,main-sequence fitting,Type Ia supernovae,Cepheids 
D)  Main-sequence fitting,parallax,Cepheids,Type Ia supernovae

Question 10

In the early 1960s,physicists named Penzias and Wilson detected a persistent noise at a wavelength of 1 mm in their radio telescope.   The persistent noise that Penzias and Wilson detected came from all directions in the sky due to:

Accepted Answer

A)  synchrotron emission from the Crab Nebula 
B)  emission from newly formed stars in the Orion Nebula 
C)  cellphone usage 
D)  photons left over from the Big Bang 
A)  synchrotron emission from the Crab Nebula 
B)  emission from newly formed stars in the Orion Nebula 
C)  cellphone usage 
D)  photons left over from the Big Bang

Question 11

The COBE and WMAP satellites (see the figure below)detected fluctuations in the CBR.On average,how big were these fluctuations,and what does that tell us about the very early universe?

Accepted Answer

The COBE and WMAP satellites detected ti

Question 12

The figure below shows the spectrum of a star whose motion compared to our star is nearly stationary within the Milky Way Galaxy.The shift in the galaxy spectrum indicates that the galaxy is moving quickly toward our own.

Accepted Answer

A) True 
 B)False

Question 13

Why can Type Ia supernovae be used to determine a galaxy's distance?

Accepted Answer

A)  Type Ia supernovae occur only in very luminous galaxies. 
B)  Type Ia supernova have approximately the same luminosity. 
C)  Type Ia supernovae have approximately the same size. 
D)  A Type Ia supernova occurs in a typical galaxy about once every 100 years. 
A)  Type Ia supernovae occur only in very luminous galaxies. 
B)  Type Ia supernova have approximately the same luminosity. 
C)  Type Ia supernovae have approximately the same size. 
D)  A Type Ia supernova occurs in a typical galaxy about once every 100 years.

Question 14

According to Hubble's law,as the distance of a galaxy __________ its __________ increases.

Accepted Answer

A)  increases; luminosity 
B)  increases; recessional velocity 
C)  decreases; luminosity 
D)  decreases; recessional velocity 
A)  increases; luminosity 
B)  increases; recessional velocity 
C)  decreases; luminosity 
D)  decreases; recessional velocity

Question 15

Type Ia supernovae have an absolute magnitude of -20.If you discover a Type Ia supernova in a distant galaxy that has an apparent magnitude of 22,then how far away is this galaxy?

Accepted Answer

A)  0.3 Mpc 
B)  40 Mpc 
C)  1,200 Mpc 
D)  2,500 Mpc 
A)  0.3 Mpc 
B)  40 Mpc 
C)  1,200 Mpc 
D)  2,500 Mpc

Question 16

Astronomers have known that galaxies are separate entities outside of our own for roughly the last:

Accepted Answer

A)  30 years 
B)  90 years 
C)  150 years 
D)  300 years 
A)  30 years 
B)  90 years 
C)  150 years 
D)  300 years

Question 17

What important event in the universe's history marked the creation of the cosmic background radiation?

Accepted Answer

The CBR is a relic of the time in the un

Question 18

If a galaxy has a recessional velocity of 880 km/s,what is its distance if the Hubble constant is 22 km/s/Mly?

Accepted Answer

A)  40 Mly 
B)  88 Mly 
C)  400 Mly 
D)  8,800 Mly 
A)  40 Mly 
B)  88 Mly 
C)  400 Mly 
D)  8,800 Mly

Question 19

Does Hubble's law imply that our galaxy is sitting at the center of the universe? Explain.

Accepted Answer

Our galaxy is not at the center of the u

Question 20

We can measure the value of H0 directly with no intermediate steps.

Accepted Answer

A) True 
 B)False

The figure below indicates a possible picture of a theoretical universe with two separate observers within it.Which of the following statements describes this universe?

The spectrum of a galaxy is observed to have a hydrogen emission line,normally found at 656.3 nm,with a measured wavelength of 856.3 nm.What is its distance if the Hubble constant is 22 km/s/Mly?

If the distance of a galaxy is 100 Mly,what is its recessional velocity if the Hubble constant is 22 km/s/Mly?

If suddenly we find that the distance between Earth and the Sun is now 10 percent larger than we thought it was before,what else will change?

Hubble's constant,H₀,represents:

Astronomers use galactic redshift as a measure of:

The existence of the cosmic background radiation tells us that the early universe was:

What did Edwin Hubble study in the Andromeda Galaxy that proved it was an individual galaxy and not part of our own Milky Way?

Which of the following lists distance indicators that are used to measure distances ranging from the very nearest to the very farthest?

In the early 1960s,physicists named Penzias and Wilson detected a persistent noise at a wavelength of 1 mm in their radio telescope. The persistent noise that Penzias and Wilson detected came from all directions in the sky due to:

The COBE and WMAP satellites (see the figure below)detected fluctuations in the CBR.On average,how big were these fluctuations,and what does that tell us about the very early universe?

The figure below shows the spectrum of a star whose motion compared to our star is nearly stationary within the Milky Way Galaxy.The shift in the galaxy spectrum indicates that the galaxy is moving quickly toward our own.

Why can Type Ia supernovae be used to determine a galaxy's distance?

According to Hubble's law,as the distance of a galaxy its increases.

Type Ia supernovae have an absolute magnitude of -20.If you discover a Type Ia supernova in a distant galaxy that has an apparent magnitude of 22,then how far away is this galaxy?

Astronomers have known that galaxies are separate entities outside of our own for roughly the last:

What important event in the universe's history marked the creation of the cosmic background radiation?

If a galaxy has a recessional velocity of 880 km/s,what is its distance if the Hubble constant is 22 km/s/Mly?

Does Hubble's law imply that our galaxy is sitting at the center of the universe? Explain.

We can measure the value of H₀ directly with no intermediate steps.

Our Place in the Universe

Patterns in the Skymotions of Earth

Laws of Motion

Light and Telescopes

The Formation of Stars and Planets

Terrestrial Worlds in the Inner Solar System

Atmospheres of Venus, Earth, and Mars

The Giant Planets

Small Bodies of the Solar System

Measuring the Stars

Our Star: The Sun

Evolution of Low-Mass Stars

Evolution of High-Mass Stars

The Realm of the Galaxies

Our Galaxy: The Milky Way

Modern Cosmology and the Origin of Structure

Life in the Universe

Filters

Exam 14: The Expansion of Space

The figure below indicates a possible picture of a theoretical universe with two separate observers within it.Which of the following statements describes this universe?

The spectrum of a galaxy is observed to have a hydrogen emission line,normally found at 656.3 nm,with a measured wavelength of 856.3 nm.What is its distance if the Hubble constant is 22 km/s/Mly?

If the distance of a galaxy is 100 Mly,what is its recessional velocity if the Hubble constant is 22 km/s/Mly?

If suddenly we find that the distance between Earth and the Sun is now 10 percent larger than we thought it was before,what else will change?

Hubble's constant,H0,represents:

Astronomers use galactic redshift as a measure of:

The existence of the cosmic background radiation tells us that the early universe was:

What did Edwin Hubble study in the Andromeda Galaxy that proved it was an individual galaxy and not part of our own Milky Way?

Which of the following lists distance indicators that are used to measure distances ranging from the very nearest to the very farthest?

In the early 1960s,physicists named Penzias and Wilson detected a persistent noise at a wavelength of 1 mm in their radio telescope. The persistent noise that Penzias and Wilson detected came from all directions in the sky due to:

The COBE and WMAP satellites (see the figure below)detected fluctuations in the CBR.On average,how big were these fluctuations,and what does that tell us about the very early universe?

The figure below shows the spectrum of a star whose motion compared to our star is nearly stationary within the Milky Way Galaxy.The shift in the galaxy spectrum indicates that the galaxy is moving quickly toward our own.

Why can Type Ia supernovae be used to determine a galaxy's distance?

According to Hubble's law,as the distance of a galaxy __________ its __________ increases.

Type Ia supernovae have an absolute magnitude of -20.If you discover a Type Ia supernova in a distant galaxy that has an apparent magnitude of 22,then how far away is this galaxy?

Astronomers have known that galaxies are separate entities outside of our own for roughly the last:

What important event in the universe's history marked the creation of the cosmic background radiation?

If a galaxy has a recessional velocity of 880 km/s,what is its distance if the Hubble constant is 22 km/s/Mly?

Does Hubble's law imply that our galaxy is sitting at the center of the universe? Explain.

We can measure the value of H0 directly with no intermediate steps.

Our Place in the Universe

Patterns in the Skymotions of Earth

Laws of Motion

Light and Telescopes

The Formation of Stars and Planets

Terrestrial Worlds in the Inner Solar System

Atmospheres of Venus, Earth, and Mars

The Giant Planets

Small Bodies of the Solar System

Measuring the Stars

Our Star: The Sun

Evolution of Low-Mass Stars

Evolution of High-Mass Stars

The Realm of the Galaxies

Our Galaxy: The Milky Way

Modern Cosmology and the Origin of Structure

Life in the Universe

Filters

Hubble's constant,H₀,represents:

According to Hubble's law,as the distance of a galaxy its increases.

We can measure the value of H₀ directly with no intermediate steps.