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MARK HARTMAN: We
said that we had

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made an observation
of what elements

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were present in the
supernova remnant.

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And we can tell what elements
were present by identifying

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which peaks were there.

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We know that each element gives
off certain energies of photons

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that have to do with the
difference between energy

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levels of the electrons, and the
electrons are bouncing around.

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And we saw that we had a
certain bunch of elements.

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And we said to
ourselves, well, we also

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know something about
supernova remnants.

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So we had this
question, why would we

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expect to find these particular
elements in a supernova

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remnant?

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And we came with two
different models.

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One was the elements
were already

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around the outside of
the star somewhere.

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And when the star blew up,
it kind of swept him up.

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The other model was
that the elements

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were created inside the star.

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And when you guys read
about star formation before,

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you read fusion--

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the process of atoms
being squished together

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in the middle of stars
does produce new elements.

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OK?

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And indeed, somebody
asked this question,

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how does another star use
the elements left behind

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by the supernova?

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These are the elements left
behind by the supernova.

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If a star is mostly made of
hydrogen and other gases.

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That's a really good question.

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And we said that
each of these models

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is going to make a
prediction about what

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we would foresee if we
observed the location

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of the different elements.

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We're going to look,
because we essentially

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said that this first model,
we expect to see the elements

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kind of further out, because
they'd be pushed out of the way

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if they were on the
surface of the star.

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Whereas here, we'd expect to see
the elements spread everywhere

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because they were
created inside the star.

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I'm not actually going to
tell you which one of these

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is correct, because this is a
perfect CAI research project.

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We're developing
these questions--

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these different models.

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When you do a project, you want
to think about things this way.

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What I see-- why
might I see this?

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Neither one of these
is completely wrong.

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But neither one of these
is completely right either.

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So it's going to be your
job, as part of the CAI,

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to come up with some
alternate models for what

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you think might be going on.

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We're going to
give you the tools

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to find the answers
for yourself.

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Now you started thinking
about well, OK, maybe

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if I looked at where
the elements were we

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could figure that out.

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That's actually a really
interesting project.