The Universe 8.8A

The Universe The universe is all space and everything in it

Components of the Universe There are lots of parts of the universe: –Stars –Nebulae –Black Holes –Galaxies And so much more!

Stars Stars are large balls of gas that create their own energy by fusing hydrogen atoms to create helium –The energy created by fusing hydrogen atoms emits light and heat

Stars Stars vary size and composition –Size and composition determine a stars energy and gravity Binary Star: Stars that revolve around each other, they look like they are blinking

Classifying Stars Stars are classified by three main characteristics: 1.Size 2.Brightness 3.Temperature

Classifying Stars Size Our sun is a medium size star There are stars in the universe large enough to fill our solar system

Classifying Stars Temperature Temperature is determined by color –Blue: Hottest (20,000-50,000*C) –White (10,000*C) –Yellow (6,000*C) –Red-Orange (4,000-5,000*C) –Red: Least Hot (3,000*C)

Classifying Stars Brightness Brightness depends on the size and temperature of a star Brightness of a star is described in two ways –Apparent Magnitude: Brightness seen from earth –Absolute magnitude: Real brightness of a star from a standard distance

Hertz-Russell Diagram Nickname: H-R Diagram This is a way to classify stars Graphs the two most important characteristics of stars: Absolute magnitude (brightness) and Temperature

Hertz-Russell Diagram Main Sequence: This is the diagonal band in the diagram where 90% of all stars fall

Lives of a star 1.Begin as Nebulas: A nebulae is a hot clouds of gas, that serves as a birth place for stars

Lives of a star 2. Protostars are formed by gravity pulling together the dust and gases until they get hot enough to fuse together

Lives of a star 3. Main sequence: 90% of stars become main sequence stars and burn through their hydrogen (to make helium) slowly

Lives of a star 4. Soon a star begins to run out of fuel: Soon the star begins to run out of Hydrogen to burn and depending on the size, depends on the death

Life of a Star A stars life depends on its mass –The smaller the star, the longer it will live –The greater the star, the shorter it will live For example: –Smaller than the sun: live 200 billion years –Sun’s size: live 10 billion years –Larger than the sun: less than 10 billion years

Death of a star Small –Medium Stars: RED GIANTS 1.As they run out of fuel, their outer layer begins to expand and they become RED GIANTS WHITE DWARF 2.When the outer layer drifts into space, only the hot core is left forming a WHITE DWARF BLACK DWARF 3.When the white dwarf stops glowing it becomes a BLACK DWARF

Death of a star Large Stars: SUPER GIANTS 1.Instead of forming a red giant, large stars form SUPER GIANTS SUPERNOVA 2.Super giants can suddenly explode creating a SUPERNOVA 3.Three outcomes to a supernova: 1.Recycled material makes a new star 2.Neutron Star can be formed: this is a very dense star (same amount of mass as the sun, but the size of Houston) 3.The star can become a black hole

Black Holes Black Holes are large objects that form dense gravity wells in space Their gravitational pull is so strong that not even light can escape it We can see them as light, energy, and other objects are absorbed into them They have no volume, but immeasurable density Video

Life of a Star Nebulae/ Protostar/ Main Sequence Red Giant White Dwarf Black Dwarf Small/Medium Size Star

Life of a Star Nebulae/ Protostar/ Main Sequence Super Giant Supernova Recycled Star Large Size Star Black Hole Neutron Star

Life of a Star

Galaxy Galaxies are made up of millions of stars, gases, and dust Galaxies are held together by gravity There are 4 different types of galaxies that are classified by their shape. –Elliptical –Spiral –Lenticular –Irregular

Elliptical Galaxy Look like a flatten ball Characteristics: –Contain billions of stars –Little gas and dust between the stars –New stars rarely form, mainly old stars in these galaxies

Spiral Galaxy Shaped like they have arms spiraled outwards This is the type of galaxy we live in

Lenticular Galaxy Galaxy with a central bulge or bar in the middle, it might also have small arms

Irregular Galaxy These galaxies do not have a regular shape

Story Time!

Kian the Sad Star Once upon a time, in a lenticular galaxy, there was a cloud of dust and gases known as a nebula. That nebula was a nursery for all baby stars, but there was one star being formed that was different from them all.

Kian the Sad Star As the heat and gravity formed the gases and dust into a baby star, or a protostar, Kian was born.

Kian the Sad Star During Kian’s main sequence days, where most stars spend 90% of their life, Kian was made fun of by the other stars because he was so massive They also picked on him because he was blue, and was too hot to be around

Kian the Sad Star Kian did not hang out with the other stars at school because they made fun of how large he was.

Kian the Sad Star 10 billion years later, Kian began to swell, becoming a super giant. He became all red, and the other kids at school joked and called him a giant red hot.

Kian the Sad Star Kian grew very sad, and as he cried. But soon his sadness turned into anger His anger got so great that he exploded into a supernova!

Kian the Sad Star Kian’s explosion caused him to become a black hole. All of his classmates watched in amazement at his transformation They were jealous that they could never be black holes because they weren't large enough stars.

Kian the Sad Star Kian was finally accepted that day by his friends for being so great! The End!

I want you to write a children book: You must include: –Type and picture of the galaxy the star is born into –All the steps in the life cycle of a small/medium or large star –Explain 2 characteristics of the star –1 hand drawn pictures to go along with the story (draw after you are done writing)