8.11.4-Galaxies & the Universe

This fuzzy band of light in the night skys is the Milky Way, our Galaxy

Galileo discovered that the light in it is actually stars.

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Multiple Choice

If you were to look up at the night sky on a clear night outside of the city you may see this moving across the sky....

• The Northern Lights

• The Milky Way Galaxy

• The Asteroid Belt

3 Main Types (based on shape)

- Spiral

- Elliptical

- Irregular

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Multiple Choice

What do scientists believe is at the center of our Milky Way Galaxy?

• A wormhole

• The Sun

• A supermassive black hole

Multiple Choice

What is the name of the galaxy we live in?

• M38

• Milky Way Galaxy

• Andromeda Galaxy

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How does our Solar System move within the Milky Way Galaxy?​

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Multiple Choice

How are galaxies held together?

• Electromagnetism

• Love

• Gravity

• Inertia

Multiple Choice

Elliptical, spiral, and irregular are all types of ______.

• solar systems

• universes

• galaxies

Multiple Choice

What type of galaxy is this?

• Spiral

• Elliptical

• Irregular 

• Samsung

Multiple Choice

What type of galaxy is this?

• Spiral

• Elliptical

• Irregular

Multiple Choice

What type of galaxy is this?

• Spiral

• Elliptical

• Irregular

Multiple Choice

What type of galaxy is this?

• Spiral

• Elliptical

• Irregular

Multiple Choice

What type of galaxy is this?

• Spiral

• Elliptical

• Irregular

Multiple Choice

What type of galaxy is the Milky Way?

• Spiral

• Elliptical

• Irregular

Multiple Choice

What type of galaxy has no defined pattern or shape?

• Spiral 

• Elliptical

• Irregular

Multiple Choice

What are the the 3 types of galaxies?

• Spiral, Gibbous, and Crescent Galaxies

• Spiral Galaxies, Irregular Galaxies, and Elliptical Galaxies

•  Milky Way, Elliptical Galaxies, and Spiral Galaxies

• Milky Way, Samsung Galaxies, and Irregular Galaxies

Multiple Choice

The type of galaxy that is composed of the older, low mass, and dwarf stars.

• Spiral

• Elliptical

• Irregular

• Constellation

Multiple Choice

How many stars are in a galaxy.

• millions or billions

• thousands

• hundreds

• dozens

Match

Match the galaxies.

• Irregular

• Spiral

• Elliptical

A galaxy with no set shape

A galaxy with arms protruding out of the center

A galaxy shaped like a ball

• A galaxy with no set shape

• A galaxy with arms protruding out of the center

• A galaxy shaped like a ball

Multiple Choice

Irregular galaxies have a distinct shape

• True

• False

Multiple Choice

What galaxy is the Milky Way?

• Irregular

• Elliptical

• Spiral

Multiple Choice

What galaxy is this?

• Irregular

• Spiral

• Elliptical

Multiple Choice

What galaxy is this?

• Spiral

• Irregular

• Elliptical

Multiple Choice

What galaxy is this?

• Elliptical

• Irregular

• Spiral

Multiple Choice

The distance light travels through space in one year is a

• space-year

• light-year

• distance-year

• solar-year

Multiple Choice

From the choices presented - which is the largest object or structure in space?

• Earth

• The Sun

• The Solar System

• The asteroid belt

Multiple Choice

The largest single object in the solar system is ______.

• Saturn

• Jupiter

• Earth

• The Sun

Multiple Choice

It would take a single beam of light about ______ years to travel across the Milky Way.

• 1 million

• 10

• 100,000

• 1 billion

Explanation Slide...

In space, there is no air, so sound has nothing to travel through. If someone were to scream in space, the sound wouldn't even leave their mouths.

Explanation Slide...

In space, there is no air, so sound has nothing to travel through. If someone were to scream in space, the sound wouldn't even leave their mouths.

Multiple Choice

Why can't anyone hear if you scream in space?

• There's no gravity in space

• There are no rules in space

• There's no air in space

• There's no vacuum in space

Match

Match the following

Spiral Galaxy

Elliptical Galaxy

Irregular Galaxy

• Spiral Galaxy

• Elliptical Galaxy

• Irregular Galaxy

Galaxy Clusters

• A group of close together galaxies is known as a galaxy cluster.

• There are many of these clusters throughout space.

• They seem to occur randomly, sometimes there are lots of clusters in one area, then almost none in others.

Irregular Galaxies

As their name suggests, irregular galaxies have no distinct or orderly shape. Many new stars are born in irregular galaxies. This is because these galaxies contain far more gas and dust than elliptical or spiral galaxies.

Spinning Galaxies

• Since the big bang, galaxies have been moving away from each other. Galaxies move in other ways, too. For example, spiral galaxies spin fast in the center, while their arms spin slower. Many scientists think that several, or perhaps most, galaxies rotate around the enormous gravitational pull of a massive black hole at their center.

Black Hole

a region in space where it is theorized that no mass or light can escape

The speed of a galaxy

The sun circles the center of the Milky Way at a speed of about a half a million miles an hour. Even at that rate, it takes the sun more than 200 million years to make one complete orbit Opens in modal popup windowaround the center of the galaxy!

Holding it all together

How do each of these gigantic galaxies stay clumped together? What keeps everything in the universe from spinning out into space? The law of universal gravitation holds each galaxy together. This same force causes you to return to the ground after you jump into the air. In the next lesson, you will learn more about the force of gravity

​Big Bang Theory

The Big Bang Theory says that everything in the universe once fit into an incredibly small area. Because this area was very hot, a powerful expansion of energy was created. Everything that was densely packed in the small area went flying out in all directions. In a blink of an eye, this microscopic area expanded into something larger than the Milky Way galaxy.

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​Within seconds, everything began to cool down. Still expanding, the building blocks of the universe began to form. After millions of years, the universe’s temperature was cool enough to allow galaxies and stars to form. To this very day, the universe is still cooling and expanding.

Multiple Choice

The Big Bang Theory suggests that our universe formed as the result of a huge explosion that sent all existing matter flying outward from a single point. The Big Bang Theory is supported by which of these observations?

• All matter in the universe is composed of the same atoms.

• All galaxies appear to be moving away from all other galaxies.

• All stars in the universe are approximately the same age.

• The universe is relatively the same temperature in all locations.

Multiple Choice

What is happening to the Universe to this day?

• The universe is getting smaller and hotter.

• The universe is staying the same.

• The universe is getting cooler and bigger.

​The Big Bang Theory is not the only theory that tries to explain the creation of the universe. However, it the most popular current theory. Scientists have discovered that galaxies are traveling away from Earth. Scientists know this by studying the color of light that the galaxies give off. Light from each galaxy appears to be shifted toward the red end of the electromagnetic spectrum. This means they are traveling away from Earth. This supports the idea of a

great expansion from the Big Bang.

Multiple Choice

What does it mean if a galaxy gives off light which has been shifted toward the red end of the electromagnetic spectrum?

• The galaxy is much older than Earth.

• The galaxy is moving away from Earth.

• The galaxy is very hot and has not cooled down yet.

• The remnants of an explosion are between the galaxy and Earth.

Multiple Choice

True or False:

The Big Bang Theory is the ONLY explanation for the origin of the universe.

• True.

• False.

Another piece of evidence that supports the Big Bang was found when scientists had

launched the Cosmic Background Explorer satellite. It precisely measured the temperature of the Cosmic Microwave Background radiation. Scientists had made temperature predictions based on starting with a hot Big Bang. The satellite found temperatures which matched with the predictions. Scientists believe this radiation is from the energy released during the first year of the Big Bang.

​Scientists have estimated that the universe was formed over 13 billion years ago. In 1995,

scientists pointed the Hubble Space Telescope into an area of space that seemed empty.

The telescope collected light for 240 hours. The images that were sent back to Earth were

amazing. Many thousands of galaxies appeared in a space as small as a grain of sand.

​If there are this many galaxies spread evenly through space, there could be over 50 billion galaxies in the universe. The farthest galaxies are over 13 billion light years away. This supports the Big Bang Theory by telling scientists how old our universe is.

Multiple Choice

The Big Bang Theory suggests that our universe originated hot long ago?

• 10 - 20 billion years ago

• 10 - 20 million years ago

• 10 - 20 thousand years ago

• 10 - 20 centuries ago

The universe’s creation is still a mystery to scientists. The Big Bang is just one theory that tries to explain the origins of the universe. Exactly how big is the universe? Where is it expanding to? These questions continue to fascinate scientists and non-scientists alike.

STEMSCOPES - 2013 Rice University.

Multiple Choice

As part of The Big Bang Theory of the formation of the Universe, scientists believe that over time, the universe is continually changing in what characteristic?

• From more dense to less dense.

• From rotating to stationary.

• From cooler to hotter.

• From very large to very small.

Multiple Choice

Cosmic Microwave Background Radiation (CMBR) is the term used to describe the residual microwave radiation observed everywhere in the universe that seems to have no single source. The observation of CMBR is used as evidence of The Big Bang Theory because it is believed to be -

• The result of collisions between neighboring galaxies.

• Particles of dust that have absorbed radioactivity.

• Radiation left over from the rapid expansion of matter.

• Light energy emitted from the source of The Big Bang.

Multiple Choice

What makes up a planetary system?

• Moons & Asteroids

• Galaxies & Nebulae

• Stars & Planets

• Comets & Meteors

Multiple Choice

What makes up a Galaxy?

• Nebulae; Asteroids & Comets

• Planetary System; Stars & Planets

• Dark Matter; Supermassive Black Holes

• Interstellar Gas & Dust

Multiple Choice

What makes up a Universe?

• Galaxies; Planetary Systems; & Stars & Planets

• Nebulae; Quasars; & Dark Matter

• Supernovas; Asteroids; & Comets

• Black Holes; Galaxies; & Nebulae

Multiple Choice

What is the size of a Galaxy based on?

• The amount of dust and gas it contains.

• The number of stars it contains.

• The age of the galaxy.

• The distance from other galaxies.

Multiple Choice

What is the name of the star in our Planetary System?

• Moon

• Jupiter

• Saturn

• The Sun.

Multiple Choice

How old is the universe?

• 13.7 million years old

• 13.7 billion years old

• 9.5 million years old

• 93 billion years old

Open Ended

How does red-shift support the Big Bang theory?

Open Ended

According to the Big Bang Theory, how has the universe changed since the beginning?

Doppler Shift!

When light from distant objects in the universe shifts (moves) to the red end of the visible specturm, the object is moving away from us

Multiple Choice

What were the original two elements in our universe?

• Lithium and Carbon
• Hydrogen and Neon
• Helium and Chlorine
• Hydrogen and Helium

Multiple Choice

As galaxies move away from our galaxy

a shift in the electromagnetic spectrum is noticed. This phenomena is

called _____________.

• redshift

• blueshift

Multiple Choice

What is the correct order of the visible light spectrum starting with the longer wavelength?

• Red, yellow, orange, blue, violet, indigo

• Violet, indigo, blue, green, yellow, orange, red

• Green, yellow, blue, indigo, red, orange

• Red, orange, yellow, green, blue, indigo, violet

Multiple Choice

What happens to the wavelengths of energy if they are moving AWAY from a source?

• The waves stretch out and get longer.

• The waves compress and get shorter.

Dark Matter - a Brief Intro

- Something is strange about the spin of many galaxies, going against the laws of Kepler.

- Based on this, it was proposed that a large % of matter within galaxies, including our own, is invisible.

- This matter helps hold galaxies together and effects the movement objects within the galaxy

Red Shift!!

Scientists believe the universe is still expanding because distant objects shift in frequency toward RED on the electromagnetic spectrum.

Multiple Choice

Word 2:

The farther away a galaxy is from Earth, the faster it is moving

• Newton's Law

• John's Law

• Hubble's Law

• Speed Law

Hubble's Law!!

If a galaxy is farther away from us, then it is moving at a greater speed.

Multiple Choice

Word 3:

A very young star with a core that is not hot enough for fusion to yet take place

• Young star

• Protostar

• Prestar

• Old star

Open Ended

What elements are part of this star?

The Doppler Effect

Explains how wavelengths of light and sound change when the source is in motion

Sound and Light Moving Towards an object

• As an object gets closer to another the waves of light or sound shorten

• On a spectograph shorter light "shifts" bluer

Sound and Light Moving Away From An Object

• As an object moves away from another the waves of light or sound lenghthen

• On a spectograph longer light "shifts" redder

Spectograph

An tool that breaks apart light into it's parts, then records the results.

Our curriculum also calls it the photographic record of light waves.

Multiple Choice

As a star moves away the light appears blue

• True

• False

Multiple Choice

The doppler effect causes the pitch of a sound to change as it moves closer

• True

• False

Multiple Select

The doppler effect uses the wavelength of sound or light.

• True

• False

Multiple Select

Scientists can tell how fast a star is moving by the size of the star.

• True

• False

Multiple Choice

A spectograph measures the doppler effect of stars.

• true

• false

Multiple Choice

The doppler effect only uses light.

• True

• False

Galaxies are Moving Away

Using the doppler effect, scientists have seen that most stars are showing a red shift, or moving away . Though there may be some objects in space moving towards our solar system, that is because we are in a space in the universe.

Multiple Choice

When an ambulance move TOWARD you it sounds ________ pitched.

• high

• low

Multiple Choice

When an ambulance move TOWARD you it sounds ________ pitched.

• high

• low

Multiple Choice

The pitch of a sound wave relates to the wave's _________________.

• Wavelength

• Frequency

Multiple Choice

the doppler effect causes a shift in...

• pitch

• wavelength

• frequency

• All of the above

Multiple Choice

You are standing on the side of the road when a police car races past you with its siren on. After the police car passes you, what happens to the pitch of the siren?

• It increases

• It decreases

• It turns red

Multiple Choice

What best describes the doppler effect?

• An apparent change in frequency of a wave due to the relative motion between a wave source and an observer

• When sound changes pitch

• When light changes color

• An apparent change in the amplitude of a wave due to the relative motion between a wave source and an observer.

Multiple Choice

Look at the picture. Who is experiencing a lower pitched sound?

• Observer A

• Observer B

• There is no difference

Multiple Choice

Look at the picture. Who is experiencing a higher pitched sound?

• Observer A

• Observer B

• There's no difference

Multiple Choice

When blueshift occurs, the perceived frequency of the wave would...

• Increase

• Decrease

• Stay the same

• Make duck sounds

Multiple Choice

When redshift occurs, the perceived frequency of the wave would...

• Increase

• Decrease

• Stay the same

• Make bird sounds

Multiple Choice

The vast majority of galaxies in our universe are moving away from us. We know this because we observe __________ in the galaxies absorption spectra.

• Redshift

• Blueshift

Multiple Choice

If a star is being observed from Earth and it's light has shifted towards the red side of the spectrum it would be...

• Moving towards the Earth

• Moving away from the Earth

• This is a trick question that cannot be answered

• It isn't a star, it is a very large blueberry.

Multiple Choice

If a star is being observed from Earth and it's light has shifted towards the blue side of the spectrum it would be...

• Moving towards the Earth

• Moving away from the Earth

• This is a trick question that cannot be answered

• It isn't a star, it is a very large blueberry.

Multiple Choice

Which discovery(ies) came from our understanding redshift/ blueshift?

• The universe is expanding

• Most galaxies are moving away from us

• All of the above

• none of the above

Multiple Choice

Use the image to identify the motion of the object relative to Earth.  Compare the absorption spectra of the star to what the star would look like if it were not moving at all relative to Earth.

• It is not moving
• It is moving away from Earth (Redshift)
• It is moving towards Earth (Blueshift)
• It is moving towards Earth (Redshift)

Multiple Choice

Use the image to identify the motion of the object relative to Earth. Compare the absorption spectra of the star to what the star would look like if it were not moving at all relative to Earth.

• It is not moving relative to Earth

• It is moving away from Earth (Redshift)

• It is moving towards Earth (Blueshift)

Multiple Choice

Light can change color due to the Doppler Effect.

• True

• False