supernova pc
DESCRIPTION
Credit: Night Sky Network:http://nightsky.jpl.nasa.gov/download-view.cfm?Doc_ID=276TRANSCRIPT
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SUPERNOVA!
What is a supernova?What is a supernova?
How dangerous are they to life on Earth?How dangerous are they to life on Earth?
How would the universe be different without How would the universe be different without supernovae?supernovae?
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A hundred years ago, we believed we lived in a quiet, safe universe . . .
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Today we know the universe is filled with powerful cosmic radiation our eyes cannot see:
• Gamma-rays• X-Rays• Fast-moving atomic particles (“Cosmic Rays”)
Much of which originates from monstrous black holes in the centers of galaxies and from . . .
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. . . neutron stars with powerful magnetic fields and more commonly from . . .
Today we know the universe is filled with powerful cosmic radiation our eyes cannot see:
• Gamma-rays• X-Rays• Fast-moving atomic particles (“Cosmic Rays”)
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Supernova!
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Where does the radiation come from?
Gamma-rays
Gamma-rays
Atomic Particles
Atomic Particles
X-raysX-rays
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Life of a Butterfly
Butterfly
Pupa
Caterpillar
Eggs
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Life of a Butterfly
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Life of a Sun-like Star
Protostars
White Dwarf
Planetary Nebula
Red Giant
Sun-like Star
Star-Forming Nebula
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Life of a Massive Star
Protostars
Black Hole
SUPERNOVA
Red Supergiant
Massive Star
Star-Forming Nebula
Neutron Star
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SUPERNOVA!
Click on image to activate movie
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A special effect of a stellar explosion . . .
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Gamma-Ray Burst (GRB)!Gamma-Ray Burst (GRB)!
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Is radiation from supernovae and GRB sources dangerous to Earth?
How close would they have to be?
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Radiation on Earth
Radioactive sources emit gamma-rays.
If we are too close to a radioactive source, like a chunk of uranium, we cannot see the radiation, but it is still harmful to us!
So how far should Earth be from cosmic radiation sources to be safe?
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Death from Exploding Stars?!
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Location of Solar SystemArtist’s
Conception of the Milky Way Galaxy
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How close would a Supernova have to be?
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Location of Solar System
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How close would a Supernova have to be?
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Location of Solar System
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How close would a Supernova have to be to be dangerous?
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Location of Solar System
Supernova: within 30 light years
Nearest Supernova Candidate: over 250 light years away!
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How close would a Gamma-Ray Burst (GRB)
source have to be?
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Location of Solar System
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Location of Solar System
GRB Danger Zone: within 8,000 light years
How close would a Gamma-Ray Burst (GRB)
source have to be?
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Location of Solar System
Our galaxy is about 100,000 light years across
Nearest detected GRB source: over a Billion light years away!
How close is the nearest Gamma-Ray Burst (GRB) source ?
GRB Danger
Zone
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Earth’s Atmosphere & Magnetic Field
Protect Earth from most high-energy radiation . . .
But prevent us from detecting it here on Earth
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The high view: getting a better look
GLAST
Swift
SuzakuXMM-Newton (X-ray Multi-Mirror Mission)
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Life from Exploding Stars!
Oxygen
Scientists have discovered that most of the heavy
elements in the universe are dispersed from stars
that go supernova.
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Life from Exploding Stars!
Silicon
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Life from Exploding Stars!
Gold
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Life from Exploding Stars!
Iron
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Life from Exploding Stars!
Without supernovae to disperse elements made in stars, there would be no planets, no life as we know it!
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So aren’t you glad we live in a universe where stars explode?
Which stars?
Orion’s stars likely to go supernova!
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What is a supernova?What is a supernova?
How dangerous are they to life on Earth?How dangerous are they to life on Earth?
How would the universe be different without How would the universe be different without supernovae?supernovae?