8.11.2-The Sun & Other Stars

Chapter 11
Stars & Galaxies
Lesson 8.11.1-The View from Earth




Mrs. Freeman's Classroom (Notes to Print

​Below, highlighted in GREEN, are the concepts we will discuss in this lesson. You should understand each of these concepts.

​

​THINK
about
these
Concepts!

​

​

​Be sure to use your textbook, Chapter 11, Lesson 2 to complete your vocabulary in your notes pages!

​

​

​Follow the slides to complete your notes pages!

Chapter 11-Stars & Galaxies
Lesson 8.11.2-The Sun & Other Stars

Let's take a look at the first question we will answer:

1. How do stars shine?

2. How are stars layered?

3. How does the Sun change over short periods of time?

4. How do scientists classify stars?

​1.

​2.

8.11.2-The Sun & Other Stars

• NUCLEAR FUSION in the core of a typical star FUSES hydrogen atoms.

• THAT process PRODUCES helium and releases vast amounts of energy. THINK CHEMICAL REACTIONS PRODUCE LIGHT!

• LIGHT ENERGY makes its way from the CORE to the star's atmosphere.

• The SUN is a TYPICAL STAR, with a core, a radiative zone, and a convection zone in its interior AND photosphere, a chromosphere, and a corona in its atmosphere.

​Topic: Energy Production and Movement

​The Sun - Basic Facts (this is important)

• The sun is a yellow dwarf star.

• It is powered by nuclear fusion.

• It takes 8 minutes for radiation from the sun to reach Earth.

Multiple Choice

Which planet is closest to the sun?

• Mars
• Earth
• Venus
• Mercury

• Burning implies combustion and fire. The sun isn't made of fire.
  
  ** The sun is made of super heated plasma (Hydrogen) that undergoes fusion.

​The sun isn't burning!

Occurs on Earth in nuclear power plants and atomic bombs. Large unstable elements like uranium are broken apart to make smaller more stable elements like lead.

Nuclear Fission

Hydrogen (H+) atoms combine to form Helium (He) which releases a large amount of energy. Stars make heavier elements by further combining atoms.

Nuclear Fusion

Energy is produced through fusion

Multiple Choice

How long does it take for the light from the sun to reach the Earth?

• 8 minutes

• 8 seconds

• 8 days

• 8 years

Multiple Choice

How old is the Earth?

• 4.6 billion years

• 13.7 billion years

• 4.6 million years

• 13.7 million years

Parts of the sun

Inner layers

• Core - Energy is produced from fusion.

• Radiation zone - Tightly packed gas where electromagnetic radiation travels.

• Convection zone - Hot gasses move to the outer portion, cold gasses fall back toward core.

Parts of the sun

Atmosphere

• Photosphere - gives off visible light

• Chromosphere - reddish layer only seen during an eclipse

• Corona - outer portion - gives off solar wind (electrically charged particles)

Parts of the sun

Other terms

• Sun spot - cooler portion of the photosphere

• Prominence - loop that link sunspot areas

• Solar flare - explosions of energy that increase the solar wind. Form when prominences connect.

​The Sun - Basic Facts (this is important)

• The sun is a yellow dwarf star.

• It is powered by nuclear fusion.

• It takes 8 minutes for radiation from the sun to reach Earth.

Let's learn . . . . something new!

THE SUN!

*When did our sun form?

*What are the layers of the sun?

*What is the composition of the sun?

*What happens in the center of the sun?

What are sunspots?

*How will our sun end it's life?

*What would happen if there was no sun?

Multiple Choice

When did the sun form?

• 4.6 billion years ago

• 2.6 billion years ago

• 46 years ago

• 5 million years ago

Multiple Select

Which of the following are parts of the sun?

• convective zone

• corona

• hydrosphere

• biosphere

• photosphere

Multiple Select

What are some of the elements found in the sun? (choose ALL correct answers)

• carbon

• hydrogen

• oxygen

• nitrogen

• helium

Fill in the Blank

Hydrogen atoms fuse together to make helium in a process called ______ _____ which releases lots of energy/radiation, electricity, and solar wind.

Fill in the Blank

______ are dark spots on the surface of the sun, where there are strong pockets of magnetism.

Multiple Choice

How will our sun end its life?

• explode

• black dwarf

• white dwarf

• cosmic dust

Open Ended

What would happen if there was NO sun? Give 2 facts.

WOW!

So, if the sun stopped shinning, how long would it take for us to know?

Interior of the Sun

• The Sun's Interior is composed of three main sections:

• Core

• Radiation Zone

• Convection Zone

The Core

• The Sun produces an A LOT of energy in the core through nuclear fusion

• Nuclear fusion occurs when HYDROGEN atoms combine to form HELIUM

• This process requires extremely high temperatures and pressure

The Radiation Zone

• The energy produced in the Sun's core moves outward through the radiation zone

• This is a region of very tightly packed gas where energy moves mainly in the form of electromagnetic radiation

• This zone is so dense that it can take over 100,000 years for the energy to move through it

The Convection Zone

• This is the outermost layer of the Sun's interior

• Hot gases rise from the bottom of the convection zone and slowly cool as they approach the top

• Cooler gases sink, forming loops of gas that move energy toward the Sun's surface

Multiple Choice

What layer of the Sun's interior produces the energy?

• Convection Zone

• Core

• Radiation Zone

• Corona

Multiple Choice

In the convection zone, ______ gas rises and ______ gas sinks.

• hotter, cooler

• cooler, hotter

Multiple Choice

The sun produces energy through what process?

• Fission

• Fusion

• Photovoltaic cells

• Photosynthesis

The Sun's Atmosphere

• The Sun's atmosphere is composed of three main sections:

• Photosphere

• Chromosphere

• Corona

The Photosphere

• Inner layer of the Sun's atmosphere

• This layer of gas is thick enough to be visible and is considered the surface layer

• When you look at an image of the Sun, you are looking at the photosphere

The Chromosphere

• Middle layer of the Sun's atmosphere

• This layer is seen as a reddish glow around the photosphere

• Can only be seen at the start and end of a total eclipse

• The Greek word chroma means "color" so the chromosphere is really the "color sphere"

The Corona

• Outer layer of the Sun's atmosphere

• Looks like a white halo around the sun

• Only seen during an eclipse

• Extends into space for millions of kilometers

• Corona means "the crown" in Latin

Multiple Choice

Which layer of the Sun's atmosphere is only seen at the beginning and end of an eclipse?

• Photosphere

• Corona

• Chromosphere

• Radiation Zone

Fill in the Blank

What is the layer of the Sun that you can see?

Features of the Sun

• Sunspots

• Prominences

• Solar flares

• Solar wind

Fill in the Blank

The Sun's layers, from innermost to outermost, are the core, the ___________, and the convection zone.

Fill in the Blank

Hydrogen combines in the core of the sun to form _?

Open Ended

What is the star closest to us?

Match

Match the following

• where fusion happens

• light is released

• sends out solar wind

• cooler area on the surface

• explosion of energy and gas

core

photosphere

corona

sun spot

solar flare

• core

• photosphere

• corona

• sun spot

• solar flare

THE SUN!

*When did our sun form?

*What are the layers of the sun?

*What is the composition of the sun?

*What happens in the center of the sun?

What are sunspots?

*How will our sun end it's life?

*What would happen if there was no sun?

Let's watch the video and find out . . .

Multiple Choice

When did the sun form?

• 4.6 billion years ago

• 2.6 billion years ago

• 46 years ago

• 5 million years ago

Multiple Select

Which of the following are parts of the sun?

• convective zone

• corona

• hydrosphere

• biosphere

• photosphere

Multiple Select

What are some of the elements found in the sun? (choose ALL correct answers)

• carbon

• hydrogen

• oxygen

• nitrogen

• helium

Fill in the Blank

Hydrogen atoms fuse together to make helium in a process called ______ _____ which releases lots of energy/radiation, electricity, and solar wind.

Fill in the Blank

______ are dark spots on the surface of the sun, where there are strong pockets of magnetism.

Multiple Choice

How will our sun end its life?

• explode

• black dwarf

• white dwarf

• cosmic dust

Open Ended

What would happen if there was NO sun? Give 2 facts.

WOW!

So, if the sun stopped shinning, how long would it take for us to know?

Chapter 11-Stars & Galaxies
Lesson 8.11.2-The Sun & Other Stars

Let's take a look at the first question we will answer:

1. How do stars shine?

2. How are stars layered?

3. How does the Sun change over short periods of time?

4. How do scientists classify stars?

​3.

8.11.2-The Sun & Other Stars

• The Sun's interior remains stable for millions of years, BUT its atmosphere can change within minutes.

• Sunspots, prominences, flares, coronal mass ejections (CMEs), and solar wind are all features of the Sun's atmosphere that change constantly.

• THESE FEATURES (listed above) can interact with Earth's magnetic field.

​Topic: The Changing Sun

​Solar Prominence

​A prominence is a bright, relatively dense, and relatively cool arched cloud of gas in the chromosphere and corona of the Sun. Looks like a Loop.

​

​

​Solar Flares

​A solar flare is a sudden, brief (typically lasting only a few minutes), and explosive release of solar magnetic energy that heats and accelerates the gas in the Sun's atmosphere.

Solar flares are brief explosions of solar magnetic energy.

​What is happening in space

​What we see

Multiple Choice

Prominences and sunspots are both:

• Jets of burning gas

• Patches on the Sun's surface

• Caused by the Sun's electromagnetic field

• Visible

Multiple Select

Which of the following correctly describes the rotation of the Sun?

• All parts of the Sun rotate together.

• The Sun rotates faster at its equator than at its pole.

• The Sun rotates slower at its equator than at its pole.

• The Sun does not rotate at all.

Sun Activity

Think about the different activities that occur on the sun.

Features of the Sun

• Sunspots

• Prominences

• Solar flares

• Solar wind

Sunspots

• Areas of gas on the Sun's surface that are cooler than the gases around them

• Cooler gases don't give off as much light

• Can be larger than the Earth

• The # of sunspots varies in a regular cycle, with the most appearing about once every 11 years

• Affects on Earth: Auroras, disruptions in power, radio, and satellites

Prominences

• Huge loops of gas that often link different parts of sunspot regions

• These loops of gas are anchored to the photosphere and extend to the corona

• Can last for months

• Can disrupt navigation systems, surges/blackouts in electrical systems, damage/disrupt satellites

Solar Flare

• A release of magnetic energy that heats gas in the Sun's atmosphere and causes an eruption into space

• Typically lasts for a few minutes

• Can cause the loss of power and satellite

Solar Winds

• Streams of electrical particles from the Sun

• Solar flares can increase the amount of particles

• Earth's magnetic field blocks the majority of solar winds except on the North and South Poles

• At the poles, the particles create electric currents that cause gas in the atmosphere to glow (Northern Lights/Southern Lights)

• Worst case scenarios: too many particles entering the atmosphere can cause magnetic storms and blackouts

Multiple Choice

Large eruptions of heated gas from the Sun's surface are called

• Prominences

• Solar winds

• Sunspots

• Solar flares

Multiple Choice

The corona sends out a stream electrical particles called the

• Solar flares

• Solar winds

• Sunspots

• Prominences

Fill in the Blank

The Sun's layers, from innermost to outermost, are the core, the ___________, and the convection zone.

Earth's energy budget allows us to track how much energy is coming in and going out. ​Incoming solar energy is either: Reflected or Radiated back to space, or Absorbed.  About 71% of the total incoming solar energy is absorbed by the Earth system.

​Where Does ALL the Sun's Energy Go?!

Multiple Choice

Earth's energy budget tracks how much energy flows in and out of Earth's climate.

• True

• False

Multiple Choice

Label part 1

• #1 Core

• #1 Radiation zone

• #1 Convection zone

• #1 Photosphere

Multiple Choice

Label part 6

• #6 Prominences

• #6 Corona

• #6 Sunspots

• #6 Photosphere

Multiple Choice

Label Part 3

• #3 Chromosphere

• #3 Radiation zone

• #3 Convection zone

• #3 Photosphere

Chapter 11-Stars & Galaxies
Lesson 8.11.2-The Sun & Other Stars

Let's take a look at the first question we will answer:

1. How do stars shine?

2. How are stars layered?

3. How does the Sun change over short periods of time?

4. How do scientists classify stars?

​4.

8.11.2-The Sun & Other Stars

• Scientists classify stars by temperature, color, and mass.

• The Hertzprung-Russell Diagram organizes stars by surface temperature and luminosity.

• The main sequence on the H-R diagram contains stars that are fusing hydrogen into helium in their cores.

• 90% of stars are found in the main sequence.

• Stars move off of the main sequence when they have used up all of the hydrogen in their cores and begin FUSING helium or carbon.

​Topic: Classifying Stars

Star Colors

• The color of a star tells us the temperature of a star

• Red stars are the coolest

• Yellow stars are hotter than red stars.

• White stars are hotter than red and yellow

• Blue stars are the hottest stars of all.

Multiple Choice

What color of star is the coolest?

• Red
• Yellow
• Blue
• White

Multiple Choice

What color of star is the hottest?

• Blue
• Red
• Yellow
• Orange

Why are some stars brighter than others?

One reason a star can seem brighter than another star is due to how much power a star has - which can also be explained as the amount of wattage it has (think of light bulbs!).

​

Stars with more power (or higher wattage) will shine brighter than those with less power (lower wattage).

Why are some stars brighter than others?

Another reason is the distance of the star from the Earth. Just because a star looks brighter, doesn’t mean it actually is brighter. The more distant an object is, the dimmer it appears. Therefore, if two stars have the same level of brightness, but one is farther away, the closer star will appear brighter than the more distant star - even though they are equally bright!

Multiple Select

What are two reasons that one star can appear brighter than another star?

• power

• size

• distance

• brightness

Multiple Choice

All stars are the same color and same size.

• True

• False

There are five main differences between planets and stars:

1. Planets always orbit around a star. Never the other way around.

2. Planets are made of rock, ice, gas or water. Stars are made of plasma.

3. Stars emit their own light. Planets don’t.

4. Planets are always colder than the stars in their system.

​

​

Difference between Stars and Planets

Multiple Choice

_________ are made of plasma.

• Planets

• Stars

Multiple Choice

Which is colder? Stars or Planet?

• Planets

• Stars

​H-R Diagram

​We classify/organize stars on the Hertzsprung-Russell diagram OR HR Diagram.

​

​Astronomers sort stars by their:

​

1. ​Temperature

2. Size or Mass

​

​Both temperature and size/mass of a star help us understand the ABSOLUTE BRIGHTNESS or how bright a star actually is.

Multiple Choice

Which Star is the HOTTEST?

• Blue

• Red

• Orange

• Yellow

Multiple Choice

Which Star is the COOLEST?

• Blue

• Red

• Orange

• Yellow

Multiple Choice

Which of the following words would describe a star that is BRIGHT

• dim

• dull

• hot

• luminous

Multiple Choice

The Hertzsprung-Russell Diagram is a tool that shows

• the composition of the stars

• all of the planets in our solar system

• relationships & differences between stars

• only 1 group of stars

Multiple Select

The position of a star on the HR Diagram can tell you

• surface temperature

• absolute magnitude (luminosity)

• distance from earth

• the galaxy that the star is in

Multiple Choice

Every star on the HR Diagram is compared to our star the Sun

• true

• false

Multiple Choice

What is the Hertzsprung-Russel Diagram?

• A map which tells the approximate location of stars in the Milky Way galaxy and their distance from Earth.

• A table that alphabetically lists stars by name and includes dates of when the star was first charted.

• A chart which organizes stars into categories based on the amount of Hydrogen they burn.

• A graph used to classify stars according to their luminosity, color, temperature, and stage.

Multiple Choice

What is found on the y axis of an H-R diagram?

• Luminosity

  (or brightness)

• Temperature

• Star Size

• Distance

Multiple Choice

As you move from the bottom to the top of the HR diagram

• Temperature increases

• Luminosity increases

• luminosity decreases

• temperature decreases

Multiple Choice

The size of the star is related to its luminosity

• false

• true

Multiple Choice

The larger the star the greater the luminosity

• false

• true

Multiple Choice

Which star is brighter than the sun?

• Sirius B

• Procyon B

• Van Maanan's Star

• Aldebaran

Multiple Choice

What determines the color of a star? 

• It's size
• It's temperature
• It's composition
• They are all the same color 

Multiple Choice

Blue stars are the _____________.

• hottest
• coolest
• smallest

Multiple Choice

Red stars are the _____________.

• hottest
• coolest
• biggest
• brightest

Multiple Choice

What is found on the x axis of an H-R diagram?

• Luminosity

  (or brightness)

• Temperature

• Star Size

• Distance

Multiple Choice

Which star has the lowest temperature?

• A
• B
• C
• D

Multiple Choice

Which star is the coldest?

• Yellow Star
• Red Star
• Orange Star
• Blue Star

Multiple Choice

Which star is the hottest?

• Yellow Star

• Red Star

• Orange Star

• Blue Star

Multiple Select

The main groups of stars are (select all that apply)

• giants

• main sequence stars

• red giants

• white dwarfs

Multiple Choice

Compared to the rest of the stars, our sun is considered...

• red Extremely Large and Cold

• white Small with a medium temperature

• yellow Medium size with medium temperature

Multiple Choice

Which category is our Sun located in?

• White Dwarfs
• Supergiants
• Main Sequence
• Giants

Multiple Choice

Which spectral class does our star, the sun, belong to?

• M
• K
• G
• F

Multiple Choice

As a whole, Giants are considered hotter than White Dwarfs.

• True
• False

Multiple Choice

True or False: White dwarfs are warmer and dimmer than giants.

• True

• False

Multiple Choice

Which star is considered a supergiant?

• Sirius B

• Sun

• Betelgeuse

• Van Maanan's Star

Multiple Choice

Which star is considered a giant star?

• Mira

• Zeta Arindani

• Barnard's Star

• Betelgeuse

Multiple Choice

Which star is considered a main sequence star?

• Vega

• Betelgeuse

• Pollux

• Van Maanan's Star

Multiple Choice

Which star is hotter than Deneb

• Procyon

• Sun

• Regel

• Banard's Star

Multiple Choice

In the diagram given, what happens as we move to the left?

• Stars Get Larger
• Stars get Colder
• Stars get hotter