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Read each slide

then use the red or

some underlined

words to complete

the organizer.

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Did it start as a bang!

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The Expanding Universe

A. The Big Bang Theory:

Idea that all matter began in

an infinitely small point and

exploded out in all

directions

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Galaxies: _____________________

_____________________________

______________________________Billions of

stars, dust,

and gas held

together by

gravity

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UNIVERSE

Let’s start out big and work our way down

VIRGO SUPER CLUSTER

LOCAL GROUP

GALAXY: BILLIONS OF

STARS, DUST AND GAS HELD

TOGETHER BY GRAVITY

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Universe

ALL space and everything that is in it.

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Supercluster

Virgo

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• ________________ was an astronomer in the 1920s who

gathered many pictures of galaxies

Who knew?

• noticed they all didn’t look alike

• decided to classify them by the way

they looked into 3 types

• “E” or _____________________

• “S” or _____________________

• “SB” or ____________________

Spiral

Barred Spiral

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Galaxies

• Galaxies are grouped

together in clusters.

• The cluster the Milky

Way belongs to is called

the Local Group.

• Three types of

galaxies:

• Cluster of galaxies

Elliptical Spiral Irregular

Three types of galaxies:

The Hubble

Tuning Fork

Where do we live? Earth’s

Galaxy—and Others

• Galaxies are

grouped together

in clusters.

• The cluster the Milky

Way belongs to is

called the Local

Group.

• Cluster of galaxies

Spiral Galaxies

• Spiral Galaxies: Circular

galaxies that have

arms curve outward

from a central hub.

–Arms are made

up of stars and

dust

• Two spiral galaxies!!

Illustration/draw and label:

Spiral Galaxy

disk

bulge

halo

Elliptical GalaxiesMost common type of galaxy; large three-dimensional

football shaped galaxies.

-Contain mostly older and dimmer stars.Vary in shape from completely round to extremely

elongated ovals. Unlike spiral galaxies

No bright nucleus at their center. Elliptical galaxies are

represented by the letter E

Divided into seven subgroups according to their shape.

These subgroups are labeled E0 to E7. E0 galaxies

nearly circular in shape while E7 galaxies are

extremely elongated or stretched out.

Illustrate / Draw Elliptical

Irregular Galaxies

• Come in many different

shapes and are smaller

and less common

• Irregular Galaxies - No

regular shape, includes

nebulas, with no central

bulge or spiral arms.

Illustrate/ Draw:

Earth’s Galaxy

• Galaxy: A large group of

stars, gas, and dust held

together by gravity.

• Milky Way: Our galaxy

which contains about 200

billion stars and many

nebulas

• Spiral Galaxies

The Milky Way Galaxy• The Milky Way is the galaxy that contains our Solar

System which is just one of the several galaxies of the

universe.

• . This name derives from its appearance as a dim

"milky" glowing band arching across the night sky, in

which the naked eye cannot distinguish individual stars.

• 100,000 light years in diameter

• Our sun orbits the center of the galaxy once every 240

million years

• A barred spiral galaxy

• Contains over 200 billion stars

• Its where we live!!!!!

Solar System

Our star (Sun), the planets, many

moons, and other small bodies that

ALL travel around the Sun

Solar System

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What do we see in the sky?• The stars move in the sky but not

with respect to each other

• The planets (or “wanderers”) move differently from stars

– They move with respect to the stars

– They exhibit strange retrograde motion

• What does all this mean?

• How can we explain these movements?

• What does the universe look like?

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The Great Debate!

• Heraclides (330 B.C.) developed

the first Solar System model,

beginning of the geocentric versus

heliocentric debate

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Timeline

Copernicus

1473-1543

Tycho

1546-1601Kepler

1571-1630

Galileo

1564-1642 Newton

1642-1727

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Geocentric (Ptolemaic) System

• The theory (in Greek, geo means

earth), which maintained that

Earth was the center of the

universe, usually referring to the

system of Claudius Ptolemy.

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Geocentric

(Ptolemaic) System

• The accepted model for

1400 years

• The earth is at the center

The Sun, stars, and

planets on their spheres

revolve around the earth: explains daily

movement

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Geocentric (Ptolemaic) System cont’…

• To account for unusual planetary

motion epicycles were introduced

• Fit the Greek model of heavenly

perfection – spheres are the perfect

shape, circular the perfect motion

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Illustrate/ Draw model:

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Heliocentric (Copernican) System

• The word "helios" in

Greek means "sun."

Heliocentric means that

the sun is at the center.

A heliocentric system is

one in which the planets

revolve around a fixed

sun.

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Helio- continued

• Thus Mercury, Venus, the Earth,

Mars, Jupiter and Saturn all

revolve around the sun. The moon

is the only celestial sphere in this

system which revolves around the

earth, and, together with it, around

the sun.

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Heliocentric (Copernican) System

• Sun at center

(heliocentric)

• Uniform, circular motion

–No epicycles (almost)

• Moon orbited the earth,

the earth orbited the sun

as another planet

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Heliocentric (Copernican) System

• Planets and stars still on

fixed spheres, stars don’t

move

• The daily motion of the

stars results from the

Earth’s spin

• The annual motion of the

stars results from the

Earth’s orbit

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Please Illustrate/ Pick one!

Our Solar System

Our solar system is made up of:

Sun

Nine planets

Their moons

Asteroids

Comets

Meteoros

Inner Planets

The inner four rocky / Terrestrial planets. These planets have hard rock crusts, and dense rock and metal cores are:

Mercury

Venus

Earth

Mars

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Mercury• Mercury is the closest planet to the Sun.

• Mercury rotates the Sun in only 88 days.

• Mercury rotates very slowly on its axis with

one day taking 58 Earth days.

• Mercury barely has any atmosphere, but

does have glaciers.

• Called a morning star. This is because

Mercury shines brightly in the early morning

just before the sun rises. It has also been

called an evening star for the same reason.

Mercury is often visible for a brief period of

time just after the Sun sets.

Venus

Sister planet to Earth Size and structure is VERY similar to Earth, often called "Earth's Twin"

Has no moons or rings

Hot, thick atmosphere

Brightest object in sky besides sun and moon (looks like bright star)

Covered with craters, volcanoes, and mountains

Earth

Third planet from sun

Only planet known to have life and liquid water

Atmosphere composed of composed of Nitrogen (78%), Oxygen (21%), and other gases (1%).

Mars

Fourth planet from sun

Appears as bright reddish color in the night sky Called "the Red Planet" because it surface is covered with iron oxide- RUST! Proves that Mars once had free oxygen molecules in its atmosphere.

Surface features volcanoes and huge dust storms

Has 2 moons: Phobos and Deimos

Outer Planets

A gas giant (sometimes also known as a jovian planet after the planet Jupiter, or giant planet) is a massive planet with a thick atmosphere of hydrogen and helium

Jupiter

Saturn

Uranus

Neptune

Jupiter

Largest planet in solar system

Brightest planet in sky

60+ moons, 5 visible from Earth

Strong magnetic field

Giant red spot

Rings have 3 parts: Halo Ring, Main Ring, Gossamer Ring

Saturn 6th planet from sun

Seven thin, flat rings not solid but made up of particles of ice, dust and rocks

31 moons

Largest moon, Titan,

Easily visible in the night sky

A lightweight planet and it spins so fast

Voyager explored Saturn and its rings.

Uranus 7th planet from sun

Has a faint ring system

27 known moons

Covered with clouds

Sits and spins on its side with the north and south poles sticking out the sides.

Neptune 8th planet from sun

Discovered through math

7 known moons

Triton largest moon

Storm called the "Great Dark Spot" because it appears as a dark oval shape on the surface of the planet.

Great Dark Spot thought to be a hole, similar to the hole in the ozone layer on Earth

Pluto our dwarf

Pluto, the outermost planet, is a small, icy "dwarf planet“ it is smaller than the Earth's Moon.

Pluto

9th planet from sun (usually)

Never visited by spacecraft

Orbits very slowly

Moon, Charon, is very close to Pluto and about the same size

Comet- chunks of ice and dust

• Has an elliptical orbit around Sun

• Has a head (nucleus and coma) and

tail.

• Tail always points away from sun.

Comets: Orbit

Asteroids-

Larger chunks of rock

Vary in size and shape

In Asteroid Belt between

Mars and Jupiter

Revolve around sun in 3-6

years

Asteroids: Illustrate /draw

Meteoroids- smaller chunks of rock and dust in space.

1. randomly move about space ; no specific orbit

2. come from remains of comets and asteroids

• Meteor- a meteoroid that burns in the atmosphere- produces a streak of light.

nickname: “Shooting star”

•MeteoriTe- a meteoroid that doesn’t burn up in the Earth’s atmosphere. It Touches Earth.