Deck 17: The Sun

Question 1

What part of the Sun do astronomers learn about when they study neutrinos from the Sun?

A)The core
B)The corona
C)Sunspots
D)The convection zone

Answer 1

The core

Question 2

Approximately how long does it take the energy produced in the Sun's core to reach the Sun's surface?

A)A second
B)A year
C)1000 years
D)100,000 years

Answer 2

100,000 years

Question 3

For which of the following reasons did the first solar neutrino experiments surprise astronomers?

A)Compared with predictions,too few solar neutrinos were detected
B)Compared with predictions,far too many solar neutrinos were detected
C)The wrong kind of solar neutrinos were detected
D)Solar neutrinos were detected only at night

Answer 3

Compared with predictions,too few solar neutrinos were detected

Question 4

The proton-proton chain,through which the Sun produces its energy,is an example of

A)A chemical reaction
B)Fission
C)Fusion
D)Radioactive decay

Question 5

What happens to the radiant energy produced in nuclear reactions in the core of the Sun?

A)It diffuses out of the Sun about 100,000 years after it is produced
B)It escapes from the Sun at the speed of light a few seconds later
C)It is quickly converted into neutrinos and immediately escapes from the Sun
D)It triggers more nuclear reactions

Question 6

In the proton-proton chain,how many protons are required to make a helium nucleus?

A)4
B)2
C)3
D)5

Question 7

The first solar neutrino telescope was made of

A)A cluster of large radio telescopes,all pointing at the Sun
B)A large tank of cleaning fluid
C)Magnetic collectors
D)A series of special lenses

Question 8

Most of the energy produced in the Sun's core is carried away from the core by

A)Neutrinos
B)Convection
C)Conduction
D)Radiation

Question 9

How was cleaning fluid used in the original solar neutrino telescope?

A)To provide chlorine atoms for the neutrinos to interact with
B)To cool the telescope
C)To focus the solar neutrinos
D)To shield the detector in the telescope from cosmic rays

Question 10

How do we know that the Sun's energy is not produced by meteoritic impacts?

A)The length of the year is too nearly constant
B)All the matter in the solar system would supply only a day of solar energy
C)There would be no sunspots if that were the case
D)Meteoritic impacts absorb energy rather than produce it

Question 11

Neutrinos are a good probe of stellar interiors because

A)They travel at the speed of light
B)They interact very weakly with matter
C)They have large masses
D)As far as we know,they are only produced in the centers of stars

Question 12

In the outer 20% of the Sun's interior,energy is transported by

A)Radiation
B)Convection
C)Winds
D)Magnetic fields

Question 13

The Sun will run out of fuel in about

A)5 trillion years
B)5 billion years
C)5 million years
D)5 thousand years

Question 14

How do we know that fission isn't responsible for the Sun's energy?

A)Fission doesn't produce enough energy per gram of fuel
B)The Sun doesn't have enough hydrogen for fission to be important
C)Fission would decrease the Sun's mass so rapidly it would be detectable
D)There isn't very much fissionable material in the Sun

Question 15

The four hydrogen nuclei that are fused together are more massive than the helium nucleus that they make.What happens to the missing mass?

A)It is converted to energy
B)It is ejected from the star in flare activity
C)It reappears later as neutrinos
D)It is resupplied to the sun by meteoroid impacts

Question 16

Approximately how long is the main sequence lifetime of the sun?

A)1 billion years
B)10 billion years
C)100 billion years
D)1,000 billion years

Question 17

What would be the approximate luminous lifetime of the Sun if it derived its energy entirely from gravitational contraction?

A)A century
B)A million years
C)100 million years
D)100 billion years

Question 18

The series of reactions that produce the Sun's energy are called

A)The solar cycle
B)Chemical reactions
C)The proton-proton chain
D)Core reactions

Question 19

If the Sun stopped producing energy in its core,approximately how long would it be before we would see the Sun start to become significantly dimmer?

A)8 minutes
B)1 year
C)100 years
D)100,000 years

Question 20

Which of the following are produced in the Sun's core and then pass out of the Sun in only a few seconds?

A)Photons
B)Neutrinos
C)Helium nuclei
D)Protons

Question 21

The Maunder minimum is

A)A period of time during which there were few if any sunspots
B)The lowest temperature found on the Sun's surface
C)The lowest latitude at which sunspots are found
D)The minimum size that a sunspot may have

Question 22

Where does the corona steadily escape into space?

A)Coronal loops
B)Transition region
C)Coronal holes
D)Above active regions

Question 23

The part of the Sun that emits most of the visible light is the

A)Chromosphere
B)Core
C)Corona
D)Photosphere

Question 24

Sunspots are

A)Associated with an 11 year activity cycle on the Sun
B)Areas of intense magnetic fields
C)Areas of low temperature compared to the surrounding gas
D)Areas associated with solar flares
E)All of these

Question 25

What are spicules?

A)Jets of gas shooting upward in the chromosphere
B)The dark cores of sunspots
C)Energetic particles produced in nuclear reactions in the Sun
D)Currents of hot gas in the interior of the Sun

Question 26

Where are coronal holes found?

A)Below the photosphere
B)Above active regions
C)Near the heliopause
D)Between active regions

Question 27

About how long does it take the solar wind to reach the Earth?

A)4 minutes
B)Hours
C)4 days
D)4 months

Question 28

Sunspots are:

A)Cool spots on the solar surface,relative to the rest of the solar surface.
B)Warm spots on the solar surface,relative to the rest of the solar surface.
C)magnetic storms that follow a 6 year cycle of activity.
D)more than one of the above.

Question 29

The outermost layer of the atmosphere of the Sun is the

A)Chromosphere
B)Corona
C)Photosphere
D)Transition region

Question 30

What are the layers of the solar atmosphere,from lowest to highest above the solar surface?

A)Chromosphere,Photosphere,Corona
B)Photosphere,Chromosphere,Corona
C)Corona,Chromosphere,Photosphere
D)Photosphere,Corona,Chromosphere

Question 31

What is the interval of time between one sunspot maximum and the next?

A)11 weeks
B)11 months
C)11 years
D)11 centuries

Question 32

Granules are

A)Holes in the Sun's corona
B)Bubbles in the Sun's photosphere
C)The dark centers of sunspots
D)The same as prominences

Question 33

The Sun's disc is limb-darkened because

A)The Sun's temperature increases inward
B)The Sun has many bright spots
C)When we look at the center of the disk,we see gamma rays from the core
D)We can only see the limb of the Sun when it is near our horizon

Question 34

What is the most abundant element in the Sun?

A)Hydrogen
B)Helium
C)Carbon
D)Positronium

Question 35

A solar flare is associated with what event?

A)Brightening of the core.
B)Increase in the solar wind.
C)Magnetic field lines forming closed loops.
D)An overall cooling of the rest of the solar surface.

Question 36

The temperature at the surface (photosphere)of the Sun is about

A)1000 K
B)5000 K
C)10,000 K
D)50,000 K
E)1,000,000 K

Question 37

Astronomers think the heliopause is about how far from the Sun?

A)1 AU
B)10 AU
C)100 AU
D)1000 AU

Question 38

Why do sunspots appear dark?

A)They emit no light
B)They are transparent and let us see deeper,darker layers
C)They are cooler than their surroundings
D)They are shadows

Question 39

The two most abundant elements in the Sun are

A)Hydrogen and helium
B)Hydrogen and lithium
C)Helium and lithium
D)Lithium and oxygen