Transcript barharbormaine life cycle of a star

By barharbormaine and angelleigh
HOW ARE STARS FORMED?
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The star goes through many stages and they are:
Small-medium stars
Nebula
Protostar
Main Sequence
Massive Main Sequence(High Mass Star)
Red Giant
Super Red Giant (High Mass Star)
Supernova(High Mass Star)
Neutron Star (High Mass Star )
Black Hole(High Mass Star)
Planetary Nebula
White Dwarf
Black Dwarf
NEBULA
 It’s made up of dust and dust particles
 The gravity begins to pull the particles in the nebula
together.
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www. skyimagelab.com/m16-eagle-spire-wire.html
notes-formation of stars
PROTOSTAR
A protostar is a dense area of gases in a nebula that might
become a star.
If a protostar never gets larger than 1/10th mass of the sun
it becomes a brown dwarf.
www. aspire.cosmic-ray.org
Notes-formation of stars
Brown Dwarf
 Brown dwarfs never hot enough to start fusion
 They shine dimly, but slowly cool off. The Brown
Dwarf is the 3rd stage of
a star.
www. Reorbit.com
Note-formation of a star
Main Sequence
 The temperature and pressure keep increasing.
 Hydrogen begins to fuse together.
 The protostar officially becomes a star when fusion
begins.
 The star is now in the Main Sequence.
 The Main Sequence is similar to Massive
Main sequence but it’s larger. The Main
Sequence is smaller.
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www. Crdlx5.yerpli.am/sun-pics/index.php?spgmGal=sunpics&spgmPic=6&spgmFilters=#pic
Notes-formation of stars
Massive Main Sequence
The Massive Main Sequence stars are the larger type of the
building of a star. During the phases of a star it’s like the
middle part of the making of a star.
www.asrtocu.unam.mx/massive_stars/
Notes-formation of a star
Red Giant
 Because it has run out of fuel, the star begins to cool, and contract. The outer
layers of the star fall inwards under gravity, and as they fall they heat up. A shell
surrounding the central core becomes hot enough to fuse protons into alphas.
So the star gains a new source of energy. The core of the star is now hotter than
it was during its normal life and this heat causes the outer parts of the star to
swell. The star becomes a giant. The radiation from the fusing shell has grown
weak by the time it reaches the surface of the star. Weak radiation is red, so the
star becomes a red giant.
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www. Historyoftheuniverse.com
Motes-formation of a star
Red Supergiant
 A red supergiant is the bigger version of a red giant - so far no surprise. But with these
stars with more than 8 to 10 solar masses (the exact value is still uncertain) the
production of energy doesn't stop at helium or carbon.A red supergiant is made of several
layers. The outer hull of red glowing hydrogen and helium is inactive. Below this is a layer
in which hydrogen is fusioned to helium. In the next layer helium is fusioned to carbon.
So it goes on until in the core iron is made. The supergiant shines extremely bright, but
only for a short time (still several hundred thousand to million years). In the end the
phase in which the star fusions sulfur and silicon to iron only lasts a few days to weeks.
From iron no more energy can be made. The core cools down and implodes. The
following supernova (of type II) disrupts the star and leaves a tiny neutron star or a black
hole behind.
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www.hubblesite.org
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Notes-formation of stars
Supernova
 A supernova is a final, gigantic explosion of a
supergiant star at the end of it’s life.
 A supernova lasts for weeks or so, but shines as bright
as a galaxy of 100 billion ordinary stars.
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www. Oberlin.edu/physics/Astronomy/supernova/index.com
www.familyhomesnetwork.com/facts/supernova.facts.html
Neutron Star
 A neutron star is a type of remenet that can result from
the gravitational collapse of a massive star.
 A typical neutron star’s mass is 1.35 and about 2.1 solar
masses.
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www.astroscu.unam..mx/neutrons/NS-Picture/NStar/Nstar_t.gif
www.absoluteastronomy.com (facts)
Black Hole
 Black holes are formed by the reminisce of dead stars.
 The black hole is so strong that anything that gets
caught in the black hole will never find a way back out.
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www. Space.about.com
www.neiu.edu/~rerebec/blackhole/facts.html
Planetary Nebula
 They are shells of gas thrown out by some stars near
the end of their lives.
 They live between 30,000 to 100,000 years.
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www.nightskyinfo.com ( Both Pic and Info)
White Dwarf
 They are created by a small red giant runs out of fuel
and cools off.
 The small squished cinder of matter is a white dwarf
star although it doesn’t shine the same way a normal
star shines.
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www.historyoftheuniverse.com/whitesdwarf.facts.html
http://www.phy.mtu.edu/apod/ap971102.html
Black Dwarf
 The black dwarf forms after the white dwarf cools off.
 A black dwarf is composed of degenerate matter.
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www.daivddarling,info/encylopedia/B/blackdwarf.html (Both Notes and Pic)