click on the topic to go to that section the theoretical...

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6th Grade

The Universe and Its Stars

2015-08-27

www.njctl.org

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Table of Contents: The Universe andIts Stars

· Theoretical Beginning of the Universe / Big Bang Theory

· Black Holes and Supernovas

· Stars

· Galaxies

Click on the topic to go to that section

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The Theoretical Beginningof the Universe / Big Bang Theory

Return to Tableof Contents

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The Beginning...

When most astronomers are asked how the Universe began, what do you believe they say is the answer?

How long ago do we believe the

Universe began?

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The Beginning...

You were correct if you said most will say the Universe began with the "Big Bang" which is an event said to have occurred

about 14 billion years ago.

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14 Billion Years Ago

A billion years is very hard for most people to understand.

It is difficult to think of anything we can picture in terms of billions.Lets use an example to try and understand how many one billion is.

With your group, try and decide what size jar you

would need to hold 1 billion pennies

hint: 1 billion = 1,000,000,000

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14 Billion Years Ago

Image: http://www.kokogiak.com/megapenny

One billion stacked pennies would be the size of FIVE school buses!

So if you wanted to represent 14 Billion pennies - how

many school buses would you need?

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Big Bang Theory

This theory states that all of the mass in the universe was once compacted into one small point thousands of times smaller than the head of a pin.

How is that possible?

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Big Bang Theory

This one spot was also hotter and more dense than any object we know of today.

It is believed our Universe began with a "Big Bang" when this small spot had a massive

explosion.

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Big Bang Theory

During the fraction of a second following the explosion, the universe expanded rapidly.

Think about what happens when you watch fireworks explode.

The same thing happened after the Big Bang. Within a fraction of a second, the universe was bigger than a galaxy and has not stopped expanding since then.

Expanding for 14 billion years. Think back to all 70 school buses!

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Big Bang Theory

You can also think of a stone hitting the surface of a pond.

The water will ripple out from that one point and the ripples will expand larger and larger, much like the expansion of the universe.

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Big Bang Theory

This theory states that every piece of matter in the universe came from this one point ... this one explosion.

Since everything is made of matter, this means that the "stuff" that makes up everything in the universe came from this one point in time. Including you!

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1 The initial explosion that resulted in the creation and expansion of the universe is known as the _____________.

A Big Bang Theory

B Milky Way

C Great Expansion

D Doppler Effect

Slide 14 (Answer) / 120

1 The initial explosion that resulted in the creation and expansion of the universe is known as the _____________.

A Big Bang Theory

B Milky Way

C Great Expansion

D Doppler Effect

[This object is a pull tab]

Ans

wer

A

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2 Following the Big Bang, the universe:

A expanded and then rapidly stopped expanding.

B expanded and has not stopped expanding since.

C rapidly expanded and then shrunk back to its original size.


2 Following the Big Bang, the universe:

A expanded and then rapidly stopped expanding.

B expanded and has not stopped expanding since.

C rapidly expanded and then shrunk back to its original size.


Ans

wer

B

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3 Scientists believe the Big Bang happened:

A 14 million years ago

B 14 trillion years ago

C 14 billion years ago

D within the last 3000 years

(Answer) / 120

3 Scientists believe the Big Bang happened:

A 14 million years ago

B 14 trillion years ago

C 14 billion years ago

D within the last 3000 years


Ans

wer C

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Evidence Supporting the Big Bang Theory

No people were around 14 billion years ago. So how did this theory come about?

In the early 1900's, an astronomer* named Edwin Hubble, discovered that various galaxies were spreading apart by examining the patterns he found when tracing their locations in the sky.

(astronomer: a scientist who studies planets, stars, and galaxies)

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Last year, you learned it is possible to estimate the distance a star is from Earth by looking at its brightness. Hubble used a number of methods to estimate how far away each star is.

But he did much more. He used the color of each star's light to determine which direction they are moving...and how fast.

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The redder the light, the faster away from us a star is moving.

His astonishing conclusion is that almost all stars are moving away from one another as if there were a massive explosion long ago.

Scientists estimate that this occurred 14 billion years ago.

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4 When looking at the night sky, the brighter stars are typically:

A farther from Earth than the dimmer stars.

B closer to Earth than the dimmer stars.

C the same distance from Earth as all other stars

D constantly moving closer to Earth


4 When looking at the night sky, the brighter stars are typically:

A farther from Earth than the dimmer stars.

B closer to Earth than the dimmer stars.

C the same distance from Earth as all other stars

D constantly moving closer to Earth[This object is a pull tab]

Ans

wer

B

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5 Which best describes the Big Bang Theory?

A The universe has always been the way it is today.

B The universe began from a dying star

C The universe was created by a single explosion

DThe universe is full of explosions, or "big bangs," that are making it expand


5 Which best describes the Big Bang Theory?

A The universe has always been the way it is today.

B The universe began from a dying star

C The universe was created by a single explosion

DThe universe is full of explosions, or "big bangs," that are making it expand


Ans

wer

C

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Inflation Theory

While almost all scientists believe in some version of the Big Bang theory, that theory only explains that there was a rapid expansion, not what caused it.

Inflation theory explains the explosion itself, and is gaining acceptance as new data is discovered every year.

photo: NASA

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"Flattening" the Universe

Inflation is said to have "flattened" the universe and it is easy to misunderstand what this means.

In order to understand this, talk with your group right now about what happens to your hands and feet when you spend a lot of time swimming in a pool. What do they look like?

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In the early stages of inflation, as the universe was very rapidly expanding, it looked much like your fingers do when you spend too much time in the water. Wrinkled.

Inflation filled in all those ridges and flattened the surface of the universe, making it smooth, the way fingers revert once out of the water.

"Flattening" the Universe

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Dark Matter

The study of the universe is far from complete...there is much more to do.

In recent years, the effect of dark matter was discovered. This invisible matter makes its presence known by its effect on the motion of the stars and galaxies.

Right now the problem is no one knows what dark matter actually is. Click on the image above for a 1 minute explanation of dark matter.

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Dark Matter

Scientists are working hard to find out what dark matter is.

Dark matter would slow the spreading of the universe the same way that a more massive Earth would stop a ball from flying as high.

It's now estimated to make up 27% of the mass of the universe!

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Dark Energy

Counteracting the effect that dark matter has in slowing the universe's expansion, dark energy has been discovered...and is seen to be speeding up the expansion of the universe.

While the expansion of nearby stars is slowing down...like a ball would if thrown straight up in the air, the expansion of the farthest stars is actually speeding up!

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Dark Energy

This amazed scientists as much as if you threw a baseball in the air and when it reached the top where it should stop, it suddenly started to go upwards faster. It doesn't seem to make sense!

Needless to say, dark energy is also not well understood yet; there are a lot of theories.

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Dark Matter and Dark Energy

Dark energy and dark matter were unknown 20 years ago. Now, they are believed to make up 95% of the mass of the universe.

Everything we thought was the universe (i.e. the stars, planets, gases,and galaxies) we now believe to be only 5% of the universe.

This is said to be the golden age of cosmology, the study of the universe. It's amazing how much more is left to be discovered and explained.

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Our Expanding Universe

According to the expanding universe theory, the space in our universe will always continue to expand, as it always has since the Big Bang occurred.

Stephen Hawking is one of the most famous physicists in the world today. He has researched and spoken on the expanding universe.

Click here to hear Stephen Hawking talk about this idea, the expanding universe

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Improving the Big Bang Theory

Just like with many ideas in Science, there are people who are critical of the Big Bang.

The idea that there was a "Big Bang" is a theory . This means that it can not completely be assumed to be fact, but it has not yet been proven wrong.

(Scientists don't aim to prove theories are true, they try to prove theories are false!)

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No matter your beliefs, scientists continue to hunt for evidence of the Big Bang Theory.

Either way, our Universe (and the stuff within it!) is here today for us to study.

The Universe

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6 In addition to gravity, __________ is believed to hold galaxies together.

A Dark Energy

B Dark Matter

C Solar Systems

D Stars


6 In addition to gravity, __________ is believed to hold galaxies together.

A Dark Energy

B Dark Matter

C Solar Systems

D Stars


Ans

wer

B

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7 An idea which has not yet been proven to be true, but has also not been disproved is known as:

A an understanding

B an idea

C a concept

D a theory


7 An idea which has not yet been proven to be true, but has also not been disproved is known as:

A an understanding

B an idea

C a concept

D a theory


Ans

wer

D

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8 Scientists believe only five percent of the universe is comprised of:

A dark energy

B all known objects

C dark matter

D gravity

(Answer) / 120

8 Scientists believe only five percent of the universe is comprised of:

A dark energy

B all known objects

C dark matter

D gravity


Ans

wer

B

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9 It is currently theorized that dark ____________ speeds up the expansion of the universe and dark _________ slows it down.

A matter, energy

B energy, matter

C matter, gravity

D energy, gravity


9 It is currently theorized that dark ____________ speeds up the expansion of the universe and dark _________ slows it down.

A matter, energy

B energy, matter

C matter, gravity

D energy, gravity


Ans

wer

A

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10 The rapid expansion of the universe following the Big Bang is known as:

A Flattening

B System Creation

C Inflation

D Bang Expansion


10 The rapid expansion of the universe following the Big Bang is known as:

A Flattening

B System Creation

C Inflation

D Bang Expansion


Ans

wer

C

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Galaxies


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What is a Galaxy?

When you look at the night sky, are you seeing the whole universe or just our galaxy?

A galaxy is a system of millions or billions of stars, together with gas and dust, held together by gravitational attraction.

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What is a Galaxy?

3

9

6

12

The truth is, we cannot see any stars in our sky which are outside our own galaxy, the Milky Way!

When we look at our galaxy in the sky, we are looking at a cross section, like we were standing on the face of a clock at 3, looking

across at 9!

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What is a Galaxy?

If you were to travel to the other side of the world, would you still see the galaxy?

Would you see the same stars?

Discuss this at your table and write your ideas below.

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Galaxy v. Universe

Some people may think that galaxy and universe can be used to mean the same thing.

The truth is, our galaxy, the Milky Way, is one of about 1.7 Billion that can be found in the entire universe!

Imag

e:

NA

SA

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11 Which term represents a larger area?

A universe

B galaxy

C they are the same


11 Which term represents a larger area?

A universe

B galaxy

C they are the same


Ans

wer

A

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12 A system of stars, gas, and dust held together by gravity is known as a/an____________.

A star system

B galaxy

C universe

D attraction


12 A system of stars, gas, and dust held together by gravity is known as a/an____________.

A star system

B galaxy

C universe

D attraction


Ans

wer

B

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"Gravitational Attraction"This phrase came up in the 1st slide on Galaxies ... but what does

it mean?

First, let's talk about gravity. Gravity is the force which keeps us on Earth. We experience gravity everyday!

Right now, come up with 3 ways you experience gravity. Write them below.

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Gravity is the force of attraction between any two bodies, based on their mass and the distance between them.

GravityThat definition works when you are younger... but we need to come up with a more correct definition for Gravity.

Click on Sir Isaac Newton, who first wrote about the theory of gravity, to discover our more complete definition.

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Gravity Lab

What would happen if these three objects were dropped from the same height at the same time?

This lab will have you examining what happens when gravity acts on various everyday objects!

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Review Mass and Weight:

Mass is the amount of matter (or "stuff") in an object. It is measured in grams, g.

Generally speaking, the more mass an object has, the more it weighs.

A paperclip has a mass of about 1 gram

Keep in mind for later mass and weight are two different things!

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13 Which of the following would NOT be an example of the force of gravity?

A The moon orbits around Earth

B Earth revolves around the Sun

CA ball hit in the air comes down into the outfielder's glove

D All of the above are examples of gravity


13 Which of the following would NOT be an example of the force of gravity?

A The moon orbits around Earth


CA ball hit in the air comes down into the outfielder's glove

D All of the above are examples of gravity[This object is a pull tab]

Ans

wer

D

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14 Mass can be best defined as:

A The weight of an object

B The amount of matter in an object

C The volume of an object

D The size of an object


14 Mass can be best defined as:

A The weight of an object

B The amount of matter in an object

C The volume of an object

D The size of an object


Ans

wer

B

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Gravity

This means that Gravity is more than just the force between you and Earth - it is the force between any two objects in the Universe.

Right now, there is an attractive force between you and your desk!

The force is so small though because you and your desk are very tiny (compared to the whole Universe that is!)

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Gravity

Image: NASA

How large that force is depends on two things: the size of the objects

and the distance between those objects.

Gravity is the force that holds

each galaxy together.

Everything in a galaxy has a

gravitational pull on the other

objects around it.

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15 Which of the following would have the most gravity between them?

A two ping pong balls 1 meter apart

B two ping pong balls 2 meters apart

C two bowling balls 1 meter apart

D two bowling balls 2 meters apart


15 Which of the following would have the most gravity between them?

A two ping pong balls 1 meter apart

B two ping pong balls 2 meters apart

C two bowling balls 1 meter apart

D two bowling balls 2 meters apart


Ans

wer

C

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16 There is gravity between you and the moon.

True

False


16 There is gravity between you and the moon.

True

False


Ans

wer True; there is a gravitational pull

between any two objects in the universe!

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17 There is gravity between the Milky Way Galaxy and other galaxies.

True

False


17 There is gravity between the Milky Way Galaxy and other galaxies.

True

False


Ans

wer

TRUE

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Center of the Galaxy

Due to gravity, galaxies are always revolving.. but what are they spinning around? Scientists believe that at the center of each galaxy is something called a black hole .

To the right is a simulated image of a black hole.

In a few days, we will focus more on black holes!

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Take a Tour of a Galaxy

Click on this space shuttle to be brought on a tour of our neighbor,

the Andromeda Galaxy.

Image: NASA

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18 The stars at the center of M31 are _________ and ________ than the stars close to the outside.

A larger, brighter

B smaller, hotter

C older, cooler

D farther away, brighter


18 The stars at the center of M31 are _________ and ________ than the stars close to the outside.

A larger, brighter

B smaller, hotter

C older, cooler

D farther away, brighter


Ans

wer

C

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19 Just like in our galaxy, the spiral arms of M31 contain gas and dust needed to make new generations of ___________.

A stars

B planets

C supernovas

D comets


19 Just like in our galaxy, the spiral arms of M31 contain gas and dust needed to make new generations of ___________.

A stars

B planets

C supernovas

D comets


Ans

wer

A

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20 The Swift telescope allows distant objects to be studied using both ________ and visible light.

A Radiant

B Solar

C Ultraviolet

D X-ray


20 The Swift telescope allows distant objects to be studied using both ________ and visible light.

A Radiant

B Solar

C Ultraviolet

D X-ray


Ans

wer

C

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Light-years

Light-years play a large role in answering our questions about the Universe - particularly when it has to do with size.

When you're trying to figure out how big a galaxy is (like in the

previous video) or how far away in space something is, scientists

measure not with meters or miles, but rather by using light-years.

A light-year is the distance a beam of light travels in one year.

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Speed of Light

A beam of light travels in a straight line at about 300 million meters per second.

If you turn a flashlight on in space, the beam of light will go on forever at 300 million meters per second!

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We call this distance one light-year .

In one year, that beam of light would have traveled just under 10 trillion kilometers (or about 6 trillion miles).

Speed of Light

That is equivalent to traveling around Earth's equator over 240 million times.

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Remember the tour you just took of our closest neighbor galaxy, the Andromeda galaxy ?

Do you remember how far away it is from Earth? Once you have your guess, click on the light beam to find out

Distance from Earth

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21 A light-year is defined as:

A The time it takes for light to travel from a flashlight to your eyes

B The distance a beam of light can travel in a year

C The time it takes for a beam of light to rotate around Earth one time (one yeaar)

D The distance from one side of the Sun to the other


21 A light-year is defined as:

A The time it takes for light to travel from a flashlight to your eyes

B The distance a beam of light can travel in a year

C The time it takes for a beam of light to rotate around Earth one time (one yeaar)

D The distance from one side of the Sun to the other


Ans

wer

B

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22 If you shine a light out into deep space, what would best describe its motion?

AThe light would eventually stop traveling after a given amount of time

B The light would bend on its own

C The light would not shine in space

DThe light would continue on in a straight line as long as nothing was in its way


22 If you shine a light out into deep space, what would best describe its motion?

AThe light would eventually stop traveling after a given amount of time

B The light would bend on its own

C The light would not shine in space

DThe light would continue on in a straight line as long as nothing was in its way


Ans

wer

D

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23 The distance between the Milky Way and Andromeda galaxies is best described as:

A 2.5 million light years

B 25 light years

C 2.5 light years

D 1 light year


23 The distance between the Milky Way and Andromeda galaxies is best described as:

A 2.5 million light years

B 25 light years

C 2.5 light years

D 1 light year


Ans

wer

A

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24 When we look at Andromeda, the image we see through our telescopes is:

A what the galaxy looks like today

B what it looked at 2.5 million years ago

C what it looks like a 2.5 light years away

D unknown how old it is


24 When we look at Andromeda, the image we see through our telescopes is:

A what the galaxy looks like today

B what it looked at 2.5 million years ago

C what it looks like a 2.5 light years away

D unknown how old it is[This object is a pull tab]

Ans

wer

B

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Stars


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What Are Stars?

Look up in the sky on any clear night and you can see a never-ending amount of small twinkling lights - we know them as stars.

Some stars are bright .. some are dim ..

some are blue .. some are yellow ..some are even red!

If you let your eyes adjust to the dark for about 20 minutes, you will notice something amazing.

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What Are Stars?

What exactly are stars?

What are they made of?

How many stars are there?

Why do they seem to move across the sky?

Come up with ideas about each of the questions below at your table right now.

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Stars

We're used to drawing stars that look like this:

Actually, stars don't look like this at all. Stars are massive balls of gas, like in this picture.

We have already discussed what force holds stars together. Do you remember what it is called?

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How Many Stars Are There?

Scientists have an analogy which helps us imagine how many stars are in the universe. In order to understand it, we will have to imagine one star is the size of a grain of sand.

Are you ready?

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One thimble of sand would hold the most stars you would possibly have seen had you been there on the darkest and clearest night in the history of Earth.

1 star = 1 grain of sand

A thimble isn't very big, is it?


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1 star = 1 grain of sand1 thimble = all the stars we can see

A wheelbarrow could hold every star in our Milky Way Galaxy. How many thimbles do you think it would take to fill that wheelbarrow?

Even still, a wheelbarrow doesn't hold very much sand, does it?


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1 star = 1 grain of sand1 thimble = all the stars we can see1 wheelbarrow = Milky Way Galaxy

To imagine the number of stars in the universe, we need a freight train carrying loads of sand.

But you need to know something about this particular train..


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We would need to watch this train pass by us very quickly - one car per second.

In order to count the total number of stars (which remember are grains of sand), how long do you think you would you have to watch the train go by? Write your guess below.


Slide 78 / 120

We would have to watch this train pass by us (without stopping) for...

Only then could we have seen a representation of how many stars are in the universe. Can you even imagine that number?


(Answer) / 120

We would have to watch this train pass by us (without stopping) for...

Only then could we have seen a representation of how many stars are in the universe. Can you even imagine that number?



Ans

wer

24 hours a day

7 days a week

12 months a year

for THREE years!!

Slide 79 / 120

We probably don't even have a number large enough to count the number of stars in the entire universe!

(Some astronomers give a rough estimate that there are 1022 stars, although this is always changing!)

1022 = 10,000,000,000,000,000,000,000


(Comparison: 1 billion = 10 9 = 1,000,000,000)

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25 What are stars?

A chunks of debris that burn as they pass through our atmosphere

B massive balls of gas

C celestial bodies that orbit the galaxy

D celestial bodies that orbit a planet


25 What are stars?

A chunks of debris that burn as they pass through our atmosphere

B massive balls of gas

C celestial bodies that orbit the galaxy

D celestial bodies that orbit a planet[This object is a pull tab]

Ans

wer

B

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26 What are stars made of?

A glowing rock

B dark matter

C very hot gas

D star dust


26 What are stars made of?

A glowing rock

B dark matter

C very hot gas

D star dust


Ans

wer

C

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27 How many stars are there?

A 10 22

B 10 11

C 10 1

D 10 50


27 How many stars are there?

A 10 22

B 10 11

C 10 1

D 10 50


Ans

wer

A

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Brightness of Stars

Why do some stars look brighter than others?

There are a few factors that affect how luminous a star is, and how bright it looks to us here on Earth.

We mentioned these earlier in the unit.

Can you remember? Write your answers below.

Slide 84 / 120

28 The further a star is from Earth, the _____________ it appears in the sky.

A brighter

B larger

C dimmer

D redder


28 The further a star is from Earth, the _____________ it appears in the sky.

A brighter

B larger

C dimmer

D redder


Ans

wer

C

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29 The increasing brightness indicates stars which are _______ than others.

A cooler

B hotter

C redder

D older

(Answer) / 120

29 The increasing brightness indicates stars which are _______ than others.

A cooler

B hotter

C redder

D older


Ans

wer

B

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30 Large stars appear __________ in the sky.

A dim

B yellow

C larger than other stars

D bright


30 Large stars appear __________ in the sky.

A dim

B yellow

C larger than other stars

D bright


Ans

wer

D

Slide 87 / 120

Brightness of Stars

Why do some stars look brighter than others?

The ____________ the star, the brighter it is.



Temperature :

Size:

Distance from Earth:

Slide 88 / 120

Brightness of StarsThe Sun!

What is the brightest star in our sky?

Click to reveal!

Slide 89 / 120

The Sun

The Sun is so important to us on Earth that we could not possibly survive without it.

At your table, try and come up with 5 reasons the Sun is so important and write them below. Be ready to share your ideas so we can make a list together!

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Our Most Important Star

The Sun is responsible for giving off light and heat (energy).

These two things play important roles in every food chain on Earth.

The Sun also powers the water cycle on our planet!

Another very important role the Sun plays is as the center of our Solar System - all the planets (including Earth) orbit the Sun.

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31 How long does it take Earth to make one full orbit around the sun?

A 1 day

B 1 month

C 1 year

D 1 century


31 How long does it take Earth to make one full orbit around the sun?

A 1 day

B 1 month

C 1 year

D 1 century


Ans

wer

C

Slide 92 / 120

The Energy of The Sun

The surface of the sun is 10,000 degrees Fahrenheit. So how much radiant energy does the sun actually provide?

A light bulb typically radiates between 40- and 100-watts.

How many 60-watt light bulbs would it take to give off the same radiation (per meter) as the sun?

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The Energy of The Sun

The Sun provides 1,360 Watts per square meter.

This means, an astronaut facing the sun (with a surface area of 0.85 square meters) would receive the energy equivalent to NINETEEN 60-watt lightbulbs!

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The Sun

The Sun is 93 million miles from Earth.

The photons of light which leave the Sun, travel across the vacuum of space at the speed of light to reach our eyes.

How long does it take for the light to reach Earth? Make a guess with your table.

(Hint: the speed of light is about 186,000 miles per second)

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The Sun

If you did your calculation, you probably found it took about 500 seconds (8 minutes 20 seconds) for the light from the Sun to finally reach the Earth.

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The Sun

The Sun is a yellow dwarf star.

This means that it is a relatively young star. The Sun is only about 4 billion years old. Compare that to the age of the universe.

Can anyone recall how old the universe is?

Yellow dwarf stars are also small compared to other older stars. In diameter, the Sun is only about 100 times larger than Earth.

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Star Sizes

Slide 98 / 120

32 The Sun is:

A the closest star to Earth

B the only star in our Solar System

C one of billions of stars in the Milky Way

D all of the above are true about the Sun


32 The Sun is:

A the closest star to Earth

B the only star in our Solar System

C one of billions of stars in the Milky Way

D all of the above are true about the Sun[This object is a pull tab]

Ans

wer

D

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The Sun's Motion

As the day goes by, what do you notice about the Sun in the sky?

Click on the Sun image to watch an amazing time lapse video of the Sun's motion (and you will also see the moon rising as well!).

Pay attention to how quickly the light fades once the Sun moves beyond the horizon.

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Does the Sun Revolve Around the Earth?

When astronomers first started to think about the stars above us, they believed that this motion of the Sun in the sky was because the Sun revolved around Earth.

In fact, they believed that Earth was at the center of the Solar System, as seen to the right.

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Heliocentric Model

This belief was challenged by an astronomer named Copernicus (left) who said that the Sun was the center of the solar system (heliocentric).

This was later proven by a scientist named Galileo (right).

Copernicus Galileo

We will spend more time on the motion of Earth in later units!

Slide 102 / 120

33 Which best describes the heliocentric idea of Copernicus and Galileo?

A The Sun revolves around Earth


C Earth and the Sun revolve around each other

D Both B and C are correct


33 Which best describes the heliocentric idea of Copernicus and Galileo?

A The Sun revolves around Earth


C Earth and the Sun revolve around each other

D Both B and C are correct


Ans

wer

B

Slide 103 / 120

Earth's Rotation and RevolutionRight now Earth is moving in two different ways:

Earth is rotating or spinning about on its axis (or center-line)

Earth is also revolving or moving around the Sun

Slide 104 / 120

34 Earth __________ around the Sun.

A Revolves

B Rotates

(Answer) / 120

34 Earth __________ around the Sun.

A Revolves

B Rotates


Ans

wer

A

Slide 105 / 120

Observing Earth's Rotation

You can see Earth rotating from

right here on the ground!

Look up at the stars on any given night and notice their position.If you look up later that night, they will have appeared to have moved!

Click the picture above to see this is action.

Slide 106 / 120

Observing Earth's Rotation

The stars in the video appeared to be moving throughout the course of that night.

This is due to Earth's rotation.

Even though the stars seem to be moving, it is Earth that is moving!

This photograph is also of the starry sky at night. How do you think the photographer took the picture?

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35 The rise and fall of the Sun each day is because of the ___________ of Earth.

A Revolution

B Rotation

C Size

D Gravity


35 The rise and fall of the Sun each day is because of the ___________ of Earth.

A Revolution

B Rotation

C Size

D Gravity


Ans

wer

B

Slide 108 / 120

Observing Earth's Revolution

Earth's revolution is a little more difficult to identify, but you definitely have noticed its results during the year!

Because of the tilt of Earth and its revolution around the Sun, the Sun appears to be at different heights throughout the year. Click on the animation below to learn about years.

http://njc.tl/ow

http://njc.tl/10s

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Observing Earth's Revolution

The Sun appears to be higher in the sky during the Summer months and lower in the sky during the Winter months!

We will be looking at how this affects our global temperatures in the next unit.

Winter

WinterSummer

SummerEquator

EquatorSun

Slide 110 / 120

Observing the Sun from the ISS

In May 2014, NASA Astronaut Rick Wiseman posted a Vine (a short time lapse video) from the International Space Station of the Sun in the sky.

Click on the image and see if you notice anything unusual in the video.

Can you or your group members come up with any explanation for this?

Slide 111 / 120

The Apparent Motion of Stars

During the day, our shadows move as the Sun "moves" across the sky. During the course of the year, our shadows are affected by the height of the Sun in the sky.

LAB: Earth's Motion - Interpreting Shadows

We can use our shadows to tell us a little bit about the relationship between Earth and the Sun, or any other star for that matter.

Slide 112 / 120

Black Holes and Supernovas


Slide 113 / 120

Two sections ago, we learned about galaxies.

At the center of each galaxy, we mentioned scientists believe there is a black hole.

Black Holes Revisited

What exactly is a black hole?

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Black Holes

Black holes are objects that have an incredibly large mass and, therefore, have the strongest gravity of anything in the universe.

They get their name "black" hole because not even light can escape its pull! This makes them colorless.

http://digg.com/video/vine-from-space-first-ever-rick-wiseman

page3svg

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Black Holes

The pull of gravity in a black holeworks the same way as spiral wishing wells you may see at a museum.

The closer objects (and light) gets to the black hole, the faster they rotate around it.

Click on the image to see this in action!

Slide 116 / 120

LAB: Black Holes - Interactive Activity

For this activity, each student will need a computer with Internet access. If there are technological limitations, students may be grouped to complete this assignment.

Click the image below to access the Black Holes Activity

The Student Handout is provided on the NJCTL website

Slide 117 / 120

Supernovas

Simply put, supernovas are exploding stars.

Just like humans and animals, stars have a lifespan. When a star reaches the end of its lifespan, it dies.

Unlike humans and animals though, when it reaches this point, it explodes!

Slide 118 / 120

Supernovas

The explosion of a star emits enough light to outshine a whole galaxy! (and remember how many stars are in a galaxy?)

All the matter of the star is expelled at a large velocity.

With your knowledge of galaxies and the universe, where do you think all the expelled matter from the star goes?

Slide 119 / 120

36 Which best describes a supernova?

A A star that is being "born"

B A star that has absorbed another star

C A star that has planets revolving around it

D A star that has reached the end of its life


36 Which best describes a supernova?

A A star that is being "born"

B A star that has absorbed another star

C A star that has planets revolving around it

D A star that has reached the end of its life[This object is a pull tab]

Ans

wer

D

http://njc.tl/ox

http://hubblesite.org/explore_astronomy/black_holes/

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37 A black hole got its name because not even _________ can escape.

A planets

B galaxies

C light

D gravity


37 A black hole got its name because not even _________ can escape.

A planets

B galaxies

C light

D gravity


Ans

wer

C

click on the topic to go to that section the theoretical...

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