the sun

radiative zone

The radiative zone is the next layer out. It has a temperature of about 4 million degrees C. Energy from the core travels through the radiative zone. The rate the energy travels is extremely slow. Light particles, called photons, can only travel a few millimeters before they hit another particle. The particles are absorbed and then released again. It may take 50 million years for a photon to travel all the way through the radiative zone.

the core

The core is the Suns innermost layer. The core is plasma. It has a temperature of around 15 million degrees Celsius (C). Nuclear fusion reactions create the immense temperature. In these reactions, hydrogen atoms fuse to form helium. This releases vast amounts of energy. The energy moves towards the outer layers of the Sun. Energy from the Suns core powers most of the solar system.

textbook_image

layers of the sun

The Sun is made almost entirely of the elements hydrogen and helium. The Sun has no solid material. Most atoms in the Sun exist as plasma. Plasma is superheated gas with an electrical charge. Because the Sun is made of gases, it does not have a defined outer boundary. Like Earth, the Sun has an internal structure. The inner three layers make up what we would actually call the Sun.

solar prominences

Another amazing feature on the Sun is solar prominences. Plasma flows along the loop that connects sunspots. This plasma forms a glowing arch. The arch is a solar prominence. Solar prominences can reach thousands of kilometers into the Suns atmosphere. Prominences can last for a day to several months. Prominences can be seen during a total solar eclipse. NASAs Solar Dynamics Observatory (SDO) was launched on February 11, 2010. SDO is studying the Suns magnetic field. This includes how the Sun affects Earths atmosphere and climate. SDO provides extremely high resolution images. The craft gathers data faster than anything that ever studied the Sun. To learn more about the SDO mission, visit: http://sdo.gsfc.nasa.gov To find these videos for download, check out: There are other ways to connect with NASA. Subscribe to NASAs Goddard Shorts HD podcast (http://svs.gsfc.nasa

the corona

The corona is the outermost part of the Suns atmosphere. It is the Suns halo, or crown. With a temperature of 1 to 3 million K, the corona is much hotter than the photosphere. The corona extends millions of kilometers into space. Sometime you should try to see a total solar eclipse. If you do you will see the Suns corona shining out into space.

surface features of the sun

The Sun has many incredible surface features. Dont try to look at them though! Looking directly at the Sun can cause blindness. Find the appropriate filters for a pair of binoculars or a telescope and enjoy!

sunspots

The most noticeable magnetic activity of the Sun is the appearance of sunspots. Sunspots are cooler, darker areas on the Suns surface (Figure 24.18). Sunspots occur in an 11 year cycle. The number of sunspots begins at a minimum. The number gradually increases to the maximum. Then the number returns to a minimum again. Sunspots form because loops of the Suns magnetic field break through the surface. Sunspots usually occur in pairs. The loop breaks through the surface where it comes out of the Sun. It breaks through again where it goes back into the Sun. Sunspots disrupt the transfer of heat from the Suns lower layers.

textbook_image

solar flares

A loop of the Suns magnetic field may break. This creates solar flares. Solar flares are violent explosions that release huge amounts of energy (Figure 24.19). The streams of high energy particles they emit make up the solar wind. Solar wind is dangerous to spacecraft and astronauts. Solar flares can even cause damage on Earth. They have knocked out entire power grids and can disturb radio, satellite, and cell phone communications.

textbook_image

the convection zone

The convection zone surrounds the radiative zone. In the convection zone, hot material from near the Suns center rises. This material cools at the surface, and then plunges back downward. The material then receives more heat from the radiative zone.

the suns atmosphere

The three outer layers of the Sun are its atmosphere.

the photosphere

The photosphere is the visible surface of the Sun (Figure 24.17). Its the part that we see shining. Surprisingly, the photosphere is also one of the coolest layers of the Sun. It is only about 6000 degrees C.

textbook_image

the chromosphere

The chromosphere lies above the photosphere. It is about 2,000 km thick. The thin chromosphere is heated by energy from the photosphere. Temperatures range from about 4000 degrees C to about 10,000 degrees C. The chromosphere is not as hot as other parts of the Sun, and it glows red. Jets of gas sometimes fly up through the chromosphere. With speeds up to 72,000 km per hour, the jets can fly as high as 10,000 kilometers.

instructional diagrams

description_image

This diagram shows the internal structure of the sun. The atmosphere lies on top and has the following layers. The corona is the outermost layer. Then lies the chromosphere, a reddish gaseous layer immediately above the photosphere of the sun or another star which, together with the corona, constitutes its outer atmosphere. The photosphere is about 300 km thick. Most of the Sun's visible light that we see originates from this region. Then lies the convection zone and the radiation zone. Then is the core which is made up of a very hot and dense mass of atomic nuclei and electrons.

description_image

The diagram represents the various parts of the sun. There are three main parts to the Sun's interior: the core, the radiative zone, and the convective zone. The core is at the center. It is the hottest region, where the nuclear fusion reactions that power the Sun occur. Moving outward, next comes the radiative (or radiation) zone. Its name is derived from the way energy is carried outward through this layer, carried by photons as thermal radiation. The third and final region of the solar interior is named the convective (or convection) zone. It is also named after the dominant mode of energy flow in this layer; heat moves upward via roiling convection, much like the bubbling motion in a pot of boiling oatmeal. The boundary between the Sun's interior and the solar atmosphere is called the photosphere. It is what we see as the visible surface of the Sun. The photosphere is not like the surface of a planet; even if you could tolerate the heat you couldn't stand on it. The sun has its own atmosphere. The lower region of the solar atmosphere is called the chromosphere. A thin transition region, where temperatures rise sharply, separates the chromosphere from the vast corona above. The uppermost portion of the Sun's atmosphere is called the corona, and is surprisingly much hotter than the Sun's surface (photosphere).

questions

The layer that shows beyond the Moon in a solar eclipse is the

-->  a. corona

b. photosphere

c. radiative zone

d. prominence zone

Which layer of the Sun contains slow moving photons?

a. corona

b. core

-->  c. radiative zone

d. convection zone

Most atoms in the Sun exist as

a. photons

-->  b. plasma

c. light

d. silicate minerals

The energy that powers the Sun comes from

-->  a. hydrogen fusing into helium

b. radioactivity

c. helium fusing into heavier elements

d. nuclear fission

Cool areas where the magnetic field disrupts the surface are

a. solar flares

b. solar prominences

c. solar winds

-->  d. sunspots

The sun makes up over 99 percent of the mass of the solar system.

-->  a. true

b. false

The suns core is made of solid rock.

a. true

-->  b. false

The sun has no atmosphere.

a. true

-->  b. false

The Suns core is molten metal.

a. true

-->  b. false

The suns energy comes from reactions in which hydrogen changes to helium.

-->  a. true

b. false

A solar flare can knock out power grids on Earth.

-->  a. true

b. false

Energy travels through the radiative zone of the sun at the speed of light.

a. true

-->  b. false

The part of the sun that we see shining is the convective zone.

a. true

-->  b. false

The Sun makes up 99.8% of the mass of the solar system.

-->  a. true

b. false

The corona is the coolest layer of the sun.

a. true

-->  b. false

The Sun does not have a defined outer boundary.

-->  a. true

b. false

Plasma is a solid.

a. true

-->  b. false

Sunspots occur because of magnetic activity of the sun.

-->  a. true

b. false

Solar wind is dangerous to spacecraft and astronauts.

-->  a. true

b. false

Solar prominences are mountains on the suns surface.

a. true

-->  b. false

Most of the atoms of the sun exist as

a. solids.

b. liquids.

c. gases.

-->  d. plasma.

Most of the solar system is powered by energy that originates in the suns

-->  a. core.

b. corona.

c. photosphere.

d. chromosphere.

Energy travels through the radiative zone of the sun as particles called

-->  a. photons.

b. protons.

c. plasmas.

d. none of the above

Which of the following statements about sunspots is false?

a. They usually occur in pairs.

b. They repeat in 11-year cycles.

c. They disrupt heat transfer in the sun.

-->  d. They are storms on the suns surface.

Solar flares occur when

-->  a. there is a break in a loop of the suns magnetic field.

b. solar wind causes fires to flare up on the suns surface.

c. nuclear reactions take place in the suns atmosphere.

d. matter inside the sun changes to the plasma state.

The hottest part of the sun is the

a. convection zone.

b. radiative zone.

c. corona.

-->  d. core.

Power grids and communication systems on Earth may be disturbed by a

a. sunspot.

-->  b. solar flare.

c. solar corona.

d. solar fusion reaction.

relatively cool, dark area on the suns surface

a. chromosphere

b. corona

c. photosphere

d. plasma

e. convection zone

f. radiative zone

-->  g. sunspot

superheated gas with an electrical charge

a. chromosphere

b. corona

c. photosphere

-->  d. plasma

e. convection zone

f. radiative zone

g. sunspot

layer of the sun that surrounds the radiative zone

a. chromosphere

b. corona

c. photosphere

d. plasma

-->  e. convection zone

f. radiative zone

g. sunspot

visible layer of the suns atmosphere

a. chromosphere

b. corona

-->  c. photosphere

d. plasma

e. convection zone

f. radiative zone

g. sunspot

layer of the suns atmosphere that glows red

-->  a. chromosphere

b. corona

c. photosphere

d. plasma

e. convection zone

f. radiative zone

g. sunspot

layer of the sun nearest the core

a. chromosphere

b. corona

c. photosphere

d. plasma

e. convection zone

-->  f. radiative zone

g. sunspot

hottest layer of the suns atmosphere

a. chromosphere

-->  b. corona

c. photosphere

d. plasma

e. convection zone

f. radiative zone

g. sunspot

diagram questions

question_image

What is the center of the sun known as?

a. THE RADIATION ZONE

b. SUNSPOTS

c. THE PROTOSPHERE?

-->  d. THE CORE

question_image

Which label refers to the core?

-->  a. Y

b. T

c. N

d. W

question_image

Which label represents the corona?

a. K

-->  b. R

c. P

d. V

question_image

Which letter represents the core?

a. R

b. V

c. P

-->  d. Y

question_image

This is the hottest portion of the sun.

a. P

-->  b. Y

c. K

d. V

question_image

What is the inner layer of the sun called?

a. RADIATIVE ZONE

-->  b. CORE

c. CONVECTIVE ZONE

d. PHOTOSPHERE

question_image

Which label shows the core?

a. Y

b. E

-->  c. W

d. D

question_image

Which letter represents the Corona?

a. N

-->  b. P

c. M

d. S

question_image

Where is the center of the Earth?

-->  a. W

b. E

c. D

d. N

question_image

Identify the corona in this picture

a. A

b. M

c. H

-->  d. C

question_image

Which label shows the core?

a. J

b. L

-->  c. H

d. A

question_image

Which phenomenon is most likely to happen after variations in the sun's magnetic field?

-->  a. SOLAR FLARES

b. SOLAR PROMINENCES

c. CORONAL EJECT_ONS

d. SUN SPOTS

question_image

By what letter is the photo-sphere represented?

a. M

b. V

-->  c. S

d. P

question_image

Which letter represents the corona?

a. M

b. S

-->  c. K

d. V

question_image

Which label shows the Inner Core?

a. V

b. J

-->  c. P

d. S

question_image

What is between the convection zone and photosphere?

a. M

b. P

-->  c. J

d. V

question_image

What is the solid portion of the Earth's nucleus?

-->  a. P

b. J

c. R

d. M

question_image

Which letter corresponds to the inner core?

-->  a. P

b. M

c. J

d. R

question_image

What is the Sun Layer Labeled P?

-->  a. PHOTOSPHERE

b. CHROMOSPHERE

c. CORONA

d. CORE

question_image

Which label shows the Radiative Zone?

a. N

b. P

c. W

-->  d. C

question_image

Identify the core in this picture

a. N

b. C

c. P

-->  d. W

question_image

How deep is layer W?

a. 1

b. 6

-->  c. 4

d. 3

question_image

Which letter corresponds to the part that's innermost in the sun?

a. C

-->  b. W

c. P

d. N

question_image

Which part of the sun is the hottest?

a. Radiative zone

b. Corona

c. Chromosphere

-->  d. Inner core

question_image

What layer of the sun lies above the photosphere?

a. subsurface flows

b. corona

c. inner core

-->  d. chromosphere

question_image

Which layer of the sun is above the convection zone and under the inner core?

a. Photosphere

-->  b. Radiative zone

c. Cromosphere

d. Subsurface

question_image

How far is the Photosphere in?

-->  a. 2

b. 1

c. 7

d. 3

question_image

How many zones are there in the internal structure of the earth?

a. 4

-->  b. 2

c. 1

d. 3

question_image

How many layers of the sun are there?

a. 4

b. 1

c. 2

-->  d. 3

question_image

What layer is just outside the Core in the Sun?

a. Photosphere

-->  b. Radiation Zone

c. Sunspots

d. Convection Zone

question_image

What's the name of the area surrounding the core?

a. photosphere

-->  b. Radiation zone

c. spot

d. convection zone

question_image

How many layers are shown in th diagram?

a. 3

b. 2

c. 1

-->  d. 4

question_image

How many sunspots can you see in the image?

-->  a. 2

b. 3

c. 1

d. 5

question_image

The sun's warmest part is the

-->  a. Core

b. Sunspots

c. Convection Zone

d. Photosphere

question_image

Which represents the cooler, darker areas on the Suns surface?

-->  a. Sunspots

b. Core

c. Radiation Zone

d. Photosphere

question_image

What is the innermost part of the sun called?

a. radiative zone

b. photosphere

c. convection zone

-->  d. core

question_image

What does the photosphere do?

a. It provides heat to the sun's core.

-->  b. It provides heat to the chromosphere.

c. It protects the corona.

d. It separates the radiative zone from the convection zone.

question_image

What is the outermost layer of the sun?

a. Chromosphere

b. Photosphere

-->  c. Corona

d. Core

question_image

What zone is around the sun's core?

-->  a. Radioactive zone

b. Chromosphere

c. Corona

d. Convection zone

question_image

How many parts is the sun made of?

a. 5

b. 4

c. 7

-->  d. 6

question_image

How many parts of the sun are shown in the diagram?

-->  a. 6

b. 4

c. 5

d. 3

question_image

The hottest layer of the sun is its:

-->  a. Core

b. Convection zone

c. Corona

d. Radiative zone

question_image

What does the outermost yellow part represent?

a. Photosphere

b. Convection zone

-->  c. Chromosphere

d. Radiative zone

question_image

What is the outer layer of the Earth?

a. convective zone

-->  b. chromosphere

c. radiative zone

d. photosphere

question_image

What lies between the core and the Convective zone?

a. Photosphere

b. Corona

c. Chromosphere

-->  d. Radiative zone

question_image

How many layers lie between the chromosphere and the core?

a. 1

-->  b. 3

c. 2

d. 4

question_image

What is the innermost part of the sun called?

a. convective zone

-->  b. core

c. radiative zone

d. chromosphere

question_image

What is the sun's innermost layer?

a. Convection Zone

b. Radiative Zone

c. Chromosphere

-->  d. Core

question_image

What is the outermost internal structure?

-->  a. Convection zone

b. Radiative zone

c. Photosphere

d. Prominence

question_image

What is the innermost layer of the sun?

a. Photosphere

b. Chromosphere

c. Corona

-->  d. Core

question_image

How many parts make up the internal structure of the Sun?

a. 1

b. 2

c. 4

-->  d. 3

question_image

The second-most inner structure of the sun is the:

-->  a. Radiative zone

b. Corona

c. Core

d. Convection zone

question_image

How is it called the outermost part of the Suns atmosphere?

a. Photosphere

b. Chromosphere

c. Prominence

-->  d. Corona

question_image

What is the cap that covers the core of chromosphere?

a. sunspot

b. corona

c. prominence

-->  d. radiative zone

question_image

Which is the cooler, darker area on the Sun's surface that occurs in an 11-year cycle?

a. Photosphere

b. Granulation on surface

-->  c. Sunspot

d. Convective zone

question_image

What is the innermost part of the sun?

a. Convective Zone

-->  b. Core

c. Chromosphere

d. Radiative Zone

question_image

Which layer of the sun surrounds the core?

a. Convective zone

-->  b. Radiative zone

c. Photosphere

d. Chromosphere

question_image

How many layers does the sun have?

a. 4

-->  b. 3

c. 6

d. 1

question_image

What is the innermost part of the sun called?

a. interface layer

b. convective zone

-->  c. core

d. radiative zone

question_image

These are the cooler, darker areas on the sun's surface.

a. Corona

b. Prominence

-->  c. Sunspots

d. Flare

question_image

Which is the deepest part?

-->  a. core

b. convective zone

c. prominence

d. radiative zone

question_image

Which of the following is a surface feature of the sun?

-->  a. Sunspots

b. Convective Zone

c. Core

d. Radiative Zone

question_image

Sunspots are seen on which part of the sun?

-->  a. Surface

b. Core

c. Coronal Hole

d. Photosphere

question_image

What is the outmost part of the sun's atmosphere?

-->  a. Corona

b. Core

c. Photosphere

d. Convective Zone

question_image

Which zone surrounds the Radiative zone?

a. The Chromosphere

b. The Photosphere

-->  c. The Convective zone

d. The core

question_image

How many zones are presented in the diagram?

a. 4

-->  b. 2

c. 3

d. 1

question_image

What are dark spots that sometimes appear on the surface of the sun?

a. Core Spots

b. Flares

c. Coronal Holes

-->  d. Sunspots

question_image

Which part of the sun is the hottest region?

a. Prominence

b. Photosphere

-->  c. Core

d. Corona

question_image

This is the innermost region of the sun.

a. Corona

b. Photosphere

c. Convection zone

-->  d. Inner core

question_image

What is the next layer after the inner core?

a. Photosphere

-->  b. Rediative Zone

c. Convection Zone

d. Subsurface Flows

question_image

Where do the nuclear reactions take place?

a. Corona

b. Rediative zone

-->  c. Inner core

d. Convection zone

question_image

How many layers does the sun have?

-->  a. 7

b. 5

c. 6

d. 8

question_image

How many total core does picture depict?

a. 7

-->  b. 6

c. 5

d. 8

question_image

What is the innermost part of the sun called?

a. convection zone

-->  b. inner core

c. subsurface flows

d. photosphere

question_image

Which zone surrounds the radiative zone?

a. photosphere

b. chromosphere

c. core

-->  d. convective zone

question_image

This region of the sun extends millions of kilometers into space.

-->  a. Corona

b. Convective Zone

c. Radiative Zone

d. Core

question_image

What is the inner layer of the sun called?

-->  a. Core

b. Photosphere

c. Convective zone

d. Chromosphere

question_image

Which layer of the sun has the lowest temperature?

a. Chromosphere

-->  b. Photosphere

c. Radiative zone

d. Convective zone

question_image

What is the innermost layer of the sun?

-->  a. Core

b. Convective Zone

c. Photoshere

d. Radiative Zone

question_image

What is the outer layer of the sun?

-->  a. Corona

b. Photosphere

c. Convective Zone

d. Radiative Zone

question_image

How many zones does the sun have?

a. 7

b. 4

-->  c. 6

d. 5

question_image

What is the innermost part of the sun called?

a. radiative zone

b. photosphere

-->  c. core

d. convective zone

question_image

Identify the corona

a. V

b. P

c. K

-->  d. R