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MARK HARTMAN: We said that we had
made an observation of what elements
were present in the supernova remnant.
And we can tell what elements were present by identifying
which peaks were there.
We know that each element gives off certain energies of photons
that have to do with the difference between energy
levels of the electrons, and the electrons are bouncing around.
And we saw that we had a certain bunch of elements.
And we said to ourselves, well, we also
know something about supernova remnants.
So we had this question, why would we
expect to find these particular elements in a supernova
remnant?
And we came with two different models.
One was the elements were already
around the outside of the star somewhere.
And when the star blew up, it kind of swept him up.
The other model was that the elements
were created inside the star.
And when you guys read about star formation before,
you read fusion--
the process of atoms being squished together
in the middle of stars does produce new elements.
OK?
And indeed, somebody asked this question,
how does another star use the elements left behind
by the supernova?
These are the elements left behind by the supernova.
If a star is mostly made of hydrogen and other gases.
That's a really good question.
And we said that each of these models
is going to make a prediction about what
we would foresee if we observed the location
of the different elements.
We're going to look, because we essentially
said that this first model, we expect to see the elements
kind of further out, because they'd be pushed out of the way
if they were on the surface of the star.
Whereas here, we'd expect to see the elements spread everywhere
because they were created inside the star.
I'm not actually going to tell you which one of these
is correct, because this is a perfect CAI research project.
We're developing these questions--
these different models.
When you do a project, you want to think about things this way.
What I see-- why might I see this?
Neither one of these is completely wrong.
But neither one of these is completely right either.
So it's going to be your job, as part of the CAI,
to come up with some alternate models for what
you think might be going on.
We're going to give you the tools
to find the answers for yourself.
Now you started thinking about well, OK, maybe
if I looked at where the elements were we
could figure that out.
That's actually a really interesting project.