SUPERNOVA!

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SUPERNOVA!

• What is a supernova?
• How dangerous are they to life on Earth?
• How would the universe be different without
  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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• 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)

. . . neutron stars with powerful magnetic fields
and more commonly from . . .
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Supernova!
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Where does the radiation come from?
X-rays
Gamma-rays
Atomic Particles
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Life of a Butterfly
Caterpillar
Eggs
Pupa
Butterfly
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Life of a Butterfly
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Life of a Sun-like Star
Sun-like Star
Protostars
Star-Forming Nebula
Red Giant
Planetary Nebula
White Dwarf
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Life of a Massive Star
Massive Star
Protostars
Red Supergiant
Star-Forming Nebula
SUPERNOVA
Neutron Star
Black Hole
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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)!
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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?!
.
Artists Conception of the Milky Way Galaxy
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How close would a Supernova have to be?
.
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How close would a Supernova have to be?
.
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How close would a Supernova have to be to be
dangerous?
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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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How close would a Gamma-Ray Burst (GRB) source
have to be?
GRB Danger Zone within 8,000 light years
.
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How close is the nearest Gamma-Ray Burst (GRB)
source ?
Nearest detected GRB source over a Billion
light years away!
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Our galaxy is about 100,000 light years across
GRB Danger Zone
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Earths 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
XMM-Newton (X-ray Multi-Mirror Mission)
Suzaku
X-rays
Swift
Gamma-rays
GLAST
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Life from Exploding Stars!
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 arent you glad we live in a universe where
stars explode?

• Which stars?
• Orions stars likely to go supernova!

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• What is a supernova?
• How dangerous are they to life on Earth?
• How would the universe be different without
  supernovae?