Download Elements from Stardust

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Elements from Stardust
Elements from Stars
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Scientists study the stars and our sun to
understand how elements (matter) were
created and why.
The sun is mostly made of Hydrogen (H).
H
PLASMA STATE
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The temperature of the sun is very hot—
15 M degrees Celsius.
At hot temperatures and high pressure,
matter exists as plasma.
In the plasma state, nuclei are stripped of
their electrons and packed tightly
together, they don’t repel each other.
P+
N
P+
N
NO ELECTRONS
P+
N
NUCLEAR FUSION
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With the high pressure and hot
temperature in the sun, nuclei of atoms
are squeezed together and they collide.
Nuclear fusion combines smaller nuclei
into larger nuclei—making bigger and
heavier atoms.
Hydrogen into Helium
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When isotopes of hydrogen fuse, they
produce nuclei of helium + HUGE amounts
of energy for us!
Hydrogen all the way to Oxygen
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As “He” builds up in the sun, bigger and
bigger nuclei can form.
H + H makes He (2p+)
He + H makes
Li (3p+)
He + He makes Be (4p+)
and so on, and so on, up to oxygen
Supernova
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With time, large stars have enough
energy to produce heavier elements
(from oxygen thru iron)
A supernova is a huge explosion
that breaks apart a massive star,
because the star becomes too
dense
The huge explosion produces the
heaviest elements
Earth has abundant amounts of
iron but also has many elements
heavier than iron. How are
these present?
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The matter that makes up Earth was
probably formed in a gigantic supernova
that occurred billions of years ago.