Question 1

Stars with masses greater than 1.1 solar masses use the ____________________ to convert hydrogen into helium and produce energy

Accepted Answer

The answer of Stars with masses greater than 1.1 solar...

Question 2

A star on the ____________________ generates enough energy from nuclear fusion to halt gravitational collapse.

Accepted Answer

The answer of A star on the ____________________ generates enough...

Question 3

If the dust around a protostar radiates most strongly at 30 microns or 30,000 nm, what is the approximate temperature of that dust? Hint: T in K = 3,000,000/wavelength in nm.

Accepted Answer

A)  100,000 K 
B)  10,000 K 
C)  1000 K 
D)  100 K 
E)  10 K 
A)  100,000 K 
B)  10,000 K 
C)  1000 K 
D)  100 K 
E)  10 K

Question 4

The sun makes most of its energy by the proton-proton cycle.

Accepted Answer

A) True 
 B)False

Question 5

A jet has an angular length of 10 seconds of arc and flows from a star at a distance of 2,000 pc. How far does this jet extend away from the star?

Accepted Answer

A)  20,000 pc 
B)  20,000 AU 
C)  20, 000 ly 
D)  20,000 miles 
E)  20,000 km 
A)  20,000 pc 
B)  20,000 AU 
C)  20, 000 ly 
D)  20,000 miles 
E)  20,000 km

Question 6

The sun has a core in which energy travels outward primarily by radiation.

Accepted Answer

A) True 
 B)False

Question 7

Stars with masses less than ____ produce most of their energy via the proton-proton chain.

Accepted Answer

A)  0.01 solar masses 
B)  0.1 solar masses 
C)  1.1 solar masses 
D)  11 solar masses 
E)  110 solar masses 
A)  0.01 solar masses 
B)  0.1 solar masses 
C)  1.1 solar masses 
D)  11 solar masses 
E)  110 solar masses

Question 8

Some young star clusters contain large numbers of protostars.

Accepted Answer

A) True 
 B)False

Question 9

The H-R diagram main-sequence of stars has a limit at the lower-mass or energy-output end because

Accepted Answer

A)  low-mass stars form from the interstellar medium very rarely. 
B)  low-mass objects are composed primarily of solids, not gases. 
C)  pressure does not depend on temperature in degenerate matter. 
D)  the lower limit represents when the radius of the star would be zero. 
E)  there is a minimum temperature for hydrogen nuclear fusion (the definition of a star). 
A)  low-mass stars form from the interstellar medium very rarely. 
B)  low-mass objects are composed primarily of solids, not gases. 
C)  pressure does not depend on temperature in degenerate matter. 
D)  the lower limit represents when the radius of the star would be zero. 
E)  there is a minimum temperature for hydrogen nuclear fusion (the definition of a star).

Question 10

The central cores of which type of star is the lowest temperature?

Accepted Answer

A)  protostars. 
B)  massive main-sequence stars. 
C)  low-mass main-sequence stars. 
A)  protostars. 
B)  massive main-sequence stars. 
C)  low-mass main-sequence stars.

Question 11

The carbon-nitrogen-oxygen cycle

Accepted Answer

A)  operates at a slightly lower temperature than the proton-proton chain. 
B)  is most efficient in star less massive than the sun. 
C)  occurs when carbon and oxygen combine to form nitrogen, which produces energy. 
D)  produces the energy responsible for bipolar flows. 
E)  combines four hydrogen nuclei to form one helium nucleus, which produces energy. 
A)  operates at a slightly lower temperature than the proton-proton chain. 
B)  is most efficient in star less massive than the sun. 
C)  occurs when carbon and oxygen combine to form nitrogen, which produces energy. 
D)  produces the energy responsible for bipolar flows. 
E)  combines four hydrogen nuclei to form one helium nucleus, which produces energy.

Question 12

The visual pink glow of the Great Nebula in Orion

Accepted Answer

A)  is a Herbig-Haro object. 
B)  is a reflection nebula of dust. 
C)  is an emission nebula of thin gas. 
D)  contains only young low mass stars. 
E)  is believed to be about 5 billion years old. 
A)  is a Herbig-Haro object. 
B)  is a reflection nebula of dust. 
C)  is an emission nebula of thin gas. 
D)  contains only young low mass stars. 
E)  is believed to be about 5 billion years old.

Question 13

Why are reflection nebulae blue in color?

Accepted Answer

The answer of Why are reflection nebulae blue in color?...

Question 14

Emission nebulae are also called ____ because they are composed of ionized hydrogen.

Accepted Answer

A)  HI regions 
B)  HII regions 
C)  Bok globules 
D)  HeI regions 
E)  reflection nebulae 
A)  HI regions 
B)  HII regions 
C)  Bok globules 
D)  HeI regions 
E)  reflection nebulae

Question 15

____ are star-like objects that contain less than 0.08 solar masses and will never raise their core temperatures high enough that the proton-proton chain can begin. Other minor fusion reactions do occur in these objects. They fall in a gap between the low-mass M dwarf stars and the massive planets in which nuclear fusion never occurs.

Accepted Answer

A)  Brown dwarfs 
B)  Herbig-Haro objects 
C)  Bok globules 
D)  T-Tauri star 
E)  Main-sequence stars 
A)  Brown dwarfs 
B)  Herbig-Haro objects 
C)  Bok globules 
D)  T-Tauri star 
E)  Main-sequence stars

Question 16

Bok globules are small, dark fragments of the interstellar medium.

Accepted Answer

A) True 
 B)False

Question 17

Pre-main-sequence stars are above and to the right of the main sequence.

Accepted Answer

A) True 
 B)False

Question 18

The average star spends ____ of its lifetime on the main sequence.

Accepted Answer

A)  1% 
B)  2% 
C)  10% 
D)  20% 
E)  90% 
A)  1% 
B)  2% 
C)  10% 
D)  20% 
E)  90%

Question 19

Why are massive stars more luminous than low mass stars? That is, why is there a mass-luminosity relation?

Accepted Answer

The answer of Why are massive stars more luminous than...

Question 20

The extinction of starlight due to the interstellar medium

Accepted Answer

A)  I & III 
B)  II & III 
C)  I & IV 
D)  II & IV 
E)  only IV 
A)  I & III 
B)  II & III 
C)  I & IV 
D)  II & IV 
E)  only IV

Stars with masses greater than 1.1 solar masses use the ____________________ to convert hydrogen into helium and produce energy

A star on the ____________________ generates enough energy from nuclear fusion to halt gravitational collapse.

If the dust around a protostar radiates most strongly at 30 microns or 30,000 nm, what is the approximate temperature of that dust? Hint: T in K = 3,000,000/wavelength in nm.

The sun makes most of its energy by the proton-proton cycle.

A jet has an angular length of 10 seconds of arc and flows from a star at a distance of 2,000 pc. How far does this jet extend away from the star?

The sun has a core in which energy travels outward primarily by radiation.

Stars with masses less than ____ produce most of their energy via the proton-proton chain.

Some young star clusters contain large numbers of protostars.

The H-R diagram main-sequence of stars has a limit at the lower-mass or energy-output end because

The central cores of which type of star is the lowest temperature?

The carbon-nitrogen-oxygen cycle

The visual pink glow of the Great Nebula in Orion

Why are reflection nebulae blue in color?

Emission nebulae are also called ____ because they are composed of ionized hydrogen.

Bok globules are small, dark fragments of the interstellar medium.

Pre-main-sequence stars are above and to the right of the main sequence.

The average star spends ____ of its lifetime on the main sequence.

Why are massive stars more luminous than low mass stars? That is, why is there a mass-luminosity relation?

The extinction of starlight due to the interstellar medium

Here and Now

A Users Guide to the Sky

Cycles of the Sun and Moon

The Origin of Modern Astronomy

Light and Telescopes

Atoms and Spectra

The Sun

The Family of Stars

The Deaths of Stars

Neutron Stars and Black Holes

The Milky Way Galaxy

Galaxies: Normal and Active

Modern Cosmology

The Origin of the Solar System

Earth and Moon: Bases for Comparative Planetology

Mercury, Venus and Mars

The Outer Solar System

Meteorites, Asteroids, and Comets

Astrobiology: Life on Other Worlds

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Exam 9: The Formation and Structure of Stars

Stars with masses greater than 1.1 solar masses use the ____________________ to convert hydrogen into helium and produce energy

A star on the ____________________ generates enough energy from nuclear fusion to halt gravitational collapse.

If the dust around a protostar radiates most strongly at 30 microns or 30,000 nm, what is the approximate temperature of that dust? Hint: T in K = 3,000,000/wavelength in nm.

The sun makes most of its energy by the proton-proton cycle.

A jet has an angular length of 10 seconds of arc and flows from a star at a distance of 2,000 pc. How far does this jet extend away from the star?

The sun has a core in which energy travels outward primarily by radiation.

Stars with masses less than ____ produce most of their energy via the proton-proton chain.

Some young star clusters contain large numbers of protostars.

The H-R diagram main-sequence of stars has a limit at the lower-mass or energy-output end because

The central cores of which type of star is the lowest temperature?

The carbon-nitrogen-oxygen cycle

The visual pink glow of the Great Nebula in Orion

Why are reflection nebulae blue in color?

Emission nebulae are also called ____ because they are composed of ionized hydrogen.

Bok globules are small, dark fragments of the interstellar medium.

Pre-main-sequence stars are above and to the right of the main sequence.

The average star spends ____ of its lifetime on the main sequence.

Why are massive stars more luminous than low mass stars? That is, why is there a mass-luminosity relation?

The extinction of starlight due to the interstellar medium

Here and Now

A Users Guide to the Sky

Cycles of the Sun and Moon

The Origin of Modern Astronomy

Light and Telescopes

Atoms and Spectra

The Sun

The Family of Stars

The Deaths of Stars

Neutron Stars and Black Holes

The Milky Way Galaxy

Galaxies: Normal and Active

Modern Cosmology

The Origin of the Solar System

Earth and Moon: Bases for Comparative Planetology

Mercury, Venus and Mars

The Outer Solar System

Meteorites, Asteroids, and Comets

Astrobiology: Life on Other Worlds

Filters