Transcript The Lifecycle of the Stars

By:
LadyFalcon12
Helium Fusiona kind of nuclear fusion
http://www.reference.com/search?q=Helium+fusion
Hydrogen Fusiona nucleus of Deuterium is formed from two protons with
the emission of an anti-electron and a neutron.
http://www.windows.ucar.edu/tour/link=/sun/Solar_interior/Nuclear_Reactions/Fusion/Fusion_in_stars/H_fusion.html
Nuclear Fusiona nuclear reaction in which nuclei combine to form
more massive nuclei with the simultaneous
release of energy
http://dictionary.reference.com/search?q=Nuclear+fusion
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A star’s life is started by a cloud of gas and
dust. This is called a Nebula.
http://simple.wikipedia.org/wiki/Stellar_evolution
A nebula is made up of hydrogen gas and plasma. This is the first
stage of a star’s life.
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http://simple.wikipedia.org/wiki/Nebula
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Facts on Nebula:
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The word nebula is Greek. It comes from the meaning of mist.
http://library.thinkquest.org/J002975F/factson3.htm.
Nebula emit light of their own.
http://www.kidscosmos.org/kid-stuff/stars-facts.html#sub4
http://www.robgendlerastropics.com/
Nebulas.html
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Like all stars small to medium stars start their lives
the same way… as a nebula.
The second stage of a star is called a Protostar. (or
known as a pre-star)
Protostar:
This is when gravity pulls atoms to the toward the center. If the cloud
becomes dense enough, gravity will collapse the cloud upon it self.
http://aspire.cosmic-ray.org/labs/star_life/nebula/nebula.html
A star can also become a Brown
Dwarf (or a small protostar)
A Brown Dwarf is a star too small
to create enough heat to start
fusion.
_life%2Fstarlife_proto.html
The next stage in becoming a star is called A
Main Sequence Star. This is when the star
does gain enough mass to begin fusion. All
main sequence stars fuse hydrogen.
 Scientists say that most of the stars percent
of stars are at this stage.
 This stage is the longest stage.
Mr. W.’s Notes
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http://www.astro.keele.ac.uk/workx/st
arlife/StarpageS_26M.html
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The next stage is Red Giant.
This stage is caused by a small to medium main
sequence star runs out of hydrogen and begins
fusing helium.
http://hubblesite.org/gallery/album/star_collection/pr1997026d/
Fusion:
is when multiple charged atomic nuclei join
together and form a heavier.
If the star isn’t fusing then it isn’t considered a
“real” star.
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http://en.wikipedia.org/wiki/Nuclear_fusion
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A Planetary Nebula is the 5th stage.
Planetary Nebula: This becomes when a red giant
completely stops fusing and the outer layers of the star drive
away.
Lifecycle of a star notes
http://commons.wikimedia.org/wiki/File:Abell39.jpg
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When the stars are at the Planetary Nebula stage they are near
the end of their lives.
http://www.nightskyinfo.com/planetary_nebulae/
Facts About Planetary Nebulae:
*The name originated in the 18th century
*planetary nebulae only last a few ten thousand years.
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White Dwarf:
The left over core of a star.
http://commons.wikimedia.org/wiki/File:G29-38_Debris_disk.jpg
Facts about White Dwarfs!!
*white dwarfs may only be the size of the earth, but it has the mass equal to half oh
the sun.
*it is the 6th stage in forming a star.
Lifecycle of a star notes
*also called a degenerate dwarf
*it is a small star made up of electron-degenerate matter.
http://en.wikipedia.org/wiki/White_dwarf
Electron-degenerate Matter:
matter which has such very high density.
http://en.wikipedia.org/wiki/Electron-degenerate_matter#Electron_degeneracy
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Black Dwarfs are white dwarfs that have
cooled off over trillions of years until it no
longer emits light.
*This is the last stage for Small to Medium Stars. *
These stars are usually found in the milky way.
http://encarta.msn.com/encyclopedia_761587611/black_dwarf.html
http://apod.nasa.gov/apod/ap000130.html
Formed the same way EXCEPT…
The 3rd stage, which is called a Red Supergiant.
Red Supergiant:
Massive main sequence star runs out of
Hydrogen and begins fusing helium, carbon,
Oxygen etc.
Lifecycle of a star notes
*15 solar masses *
http://hyperphysics.phy-astr.gsu.edu/HBASE/astro/redsup.html
http://www.nasa.gov/multimedia/imagegallery/image_feature_784.html
A Supernova is when fusion stops. The star
collapses and creates a huge explosion.
Lifecycle of stars notes
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They are extremely luminous and cause a burst
of radiation that often briefly outshines an
entire galaxy.
It takes over several months or weeks
dust to totally clear from the galaxy.
http://en.wikipedia.org/wiki/Supernova
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A Neutron Star is a super dense core of a star
left over after a supernova.
They are only 5 to 15 miles on diameter but
have a mass 1.5-2.0 times that of the sun.
This is the 5th stage in forming a high mass
star.
Lifecycle of a star notes
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http://chandra.harvard.edu/photo/category/neutronstars.html
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A Black Hole:
Stars with masses of 25x to 50x of the sin form black
holes after a supernova.
The leftover core of a star is so dense that it causes the
gravitational collapse.
Lifecycle of a star notes.
>Once a star (or anything for that matter) falls into the
black hole it will never be able to excape its gravitational
pull.
>a black hole may reveal its presence through interaction
with matter orbiting the event horizon
http://en.wikipedia.org/wiki/Black_hole
http://chandra.harvard.edu/photo/cat
egory/blackholes.html