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AUDIENCE: [INAUDIBLE]
the solar system itself.

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MARK HARTMAN: OK.

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It's much larger than
the solar system.

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That was interesting,
because why?

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Did you expect it to be smaller?

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AUDIENCE: Yeah.

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I expected it to be
smaller because when

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I looked at the visual,
it was much smaller.

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MARK HARTMAN: When you
looked at the visual.

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AUDIENCE: [INAUDIBLE]

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MARK HARTMAN: It's hard to tell.

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When you're looking at stuff
that's way out in space,

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you can't tell if it's
big or little, right?

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OK.

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What about another really
important observation?

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Because that's-- before the CAI,
you didn't know how to do this.

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So if somebody showed you
a picture of a supernova

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remnant--

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can we have everybody turn
their monitors off please?

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So before CAI, you could
look at that picture and say,

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I don't know how big that is.

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But now you can compare
that to something and see,

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does that make sense or not?

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What was another important
observation that we made?

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Steve?

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AUDIENCE: [INAUDIBLE]
image, it produced

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extra and the [INAUDIBLE].

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MARK HARTMAN: OK.

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In the center of
the object there

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was a point that was
producing lots of x-rays.

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There was high flux.

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And what did we see when
we looked at it invisible?

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AUDIENCE: Nothing.

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AUDIENCE: It's not there.

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MARK HARTMAN: It's not there.

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What does that mean
in terms of what's

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happening with that object?

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AUDIENCE: [INAUDIBLE].

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MARK HARTMAN: OK.

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So there's something
there in the middle that's

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producing X-ray light, but
not producing visible light.

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Anybody have an--
go ahead, Nikki.

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AUDIENCE: In our
[INAUDIBLE],, what

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we did for the visible light,
you could see some of it,

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but only at the very top of
the curve from the remnants.

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It could produce some visible
light, but not the whole thing.

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So there could be some extra
visible light [INAUDIBLE]..

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MARK HARTMAN: OK.

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That was a great sentence.

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So there was that
part at the top where

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we saw high flux in our
false color X-ray image,

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but we also saw high flux in
our false color visible image.

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But the bottom part of
the supernova remnant

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didn't show that.

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What's going on there?

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That must mean there's part
of it that's giving off

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both x-rays and
visible light, and part

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that's only giving off x-rays.

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Juan?

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Go ahead.

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AUDIENCE: We could determine the
true color x-ray where the high

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photons--

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where--

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MARK HARTMAN: Take your time.

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AUDIENCE: Where the high
photons [INAUDIBLE]..

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MARK HARTMAN: Take your time.

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AUDIENCE: Where is this
part of the supernova that

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is giving high photons plots.

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No, wait.

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MARK HARTMAN: No,
that sounded good.

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AUDIENCE: Like, because you
can see at the right hand side,

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it was blue.

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So we all know that blue
is high [INAUDIBLE]----

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high energy.

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MARK HARTMAN: High energy
photons we colored blue.

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AUDIENCE: And where it's red,
you know that it's low energy.

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So with the true
color image, we can

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determine where are the high
intensity and low intensity.

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MARK HARTMAN: That was
actually very, very good.

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By looking at that
true color image,

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we could tell in some regions
the light being given off

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00:04:00,090 --> 00:04:02,732
was different, just
like we saw up there.

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00:04:02,732 --> 00:04:04,190
If we look back
over there, there's

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00:04:04,190 --> 00:04:07,790
some places where there's lots
of blue light in the middle.

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Why is that colored blue?

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Because there's high-- that
indicates high energy photons.

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So we saw that from
our supernova remnant,

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00:04:16,500 --> 00:04:19,290
one side was kind of blue,
one side was kind of red.

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00:04:19,290 --> 00:04:21,784
There were different--
other parts that were green.

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Go ahead, Nikki.

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AUDIENCE: And
there's a big part,

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00:04:24,258 --> 00:04:27,850
kind of at the edge in
ours, that there's a light.

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00:04:27,850 --> 00:04:32,840
So they could be all colors
combined equally [INAUDIBLE]..

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00:04:36,734 --> 00:04:37,650
MARK HARTMAN: Exactly.

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And if we see a big
white part, that

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means we're getting
an equal amount

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of the high, medium,
and low energy

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photons from that region.

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AUDIENCE: [INAUDIBLE].

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00:04:52,072 --> 00:04:52,780
MARK HARTMAN: OK.

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AUDIENCE: [INAUDIBLE]

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MARK HARTMAN: I don't
know if you guys made

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quite the observations
that we made,

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but-- and that's interesting.

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Remember at lunch
Mike was talking

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about different
teams of people are

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00:05:03,630 --> 00:05:05,800
working on different
parts of the object.

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So yeah.

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It could be that these
guys noticed one thing,

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but you didn't.

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And until you got together
at your conference

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and you talked
about what you saw,

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and you wouldn't know if
what you saw was real or not.

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Maybe you made a mistake.

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00:05:18,600 --> 00:05:20,460
We found a couple of
mistakes in our math

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00:05:20,460 --> 00:05:24,930
here, because we transferred
knowledge and talked

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back and forth a little bit.

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So this is a really good start.

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And what I'm hoping
that it does is

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00:05:32,220 --> 00:05:34,260
by going through
this first analysis,

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it gives you a chance to ask a
few more questions about what

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00:05:36,780 --> 00:05:38,880
you think is going on, right?

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00:05:38,880 --> 00:05:41,940
Because we've identified two
more important things, actually

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00:05:41,940 --> 00:05:45,150
three more important things.

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We have identified--
so let's just

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say this is important
points from the analysis.

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And I'm going to go
ahead and move this.

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The color is not
the same everywhere.

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That's what we saw even before.

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That was one of our observations
about those different supernova

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remnants.

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What that means is light
of different energy

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00:06:31,370 --> 00:06:34,250
is being produced
in different places.

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We | saw that not all parts
of the supernova remnant

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produce visible light.

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Now that give us a clue
as to the production

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mechanism of light, right?

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We're looking at X-ray objects.

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We're looking at--
well, we're looking

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00:07:01,820 --> 00:07:04,010
at objects that give
off lots of X-ray light,

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00:07:04,010 --> 00:07:07,220
not things that give off
a lot of visible light.

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Now in general, we could say
that things that give off

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x-rays are typically hotter.

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Does it make sense that
this object is really hot?

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Why?

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AUDIENCE: [INAUDIBLE] X-rays
affect the whole supernova

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remnant.

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But with the visible
light, you can hardly

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see anything [INAUDIBLE].

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MARK HARTMAN: So
that's our observation

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that lets us know this, but
connect that to the model.

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What did the supernova
remnant used to be?

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AUDIENCE: A sun-- star.

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MARK HARTMAN: Used to be a star.

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And then what happened to it?

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AUDIENCE: [INAUDIBLE].

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MARK HARTMAN: OK.

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Steve?

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AUDIENCE: I have a question.

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MARK HARTMAN: Yeah.

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AUDIENCE: If it's [INAUDIBLE]
to produce X-rays, [INAUDIBLE],,

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won't it be producing
visible light, then?

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MARK HARTMAN: OK.

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So if you have a regular--

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like a black body, right, if
you turn the temperature way up

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it's going to have more
x-rays that it gives out.

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But you're also saying, wouldn't
it also give out visible light?

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AUDIENCE: Yeah.

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MARK HARTMAN: OK.

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So maybe this isn't quite
what we're thinking.

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Maybe it's not just that
it's really hot, OK?

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We're going to find out
that there's definitely

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some non-thermal processes
that are happening

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inside the supernova remnant.

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OK.

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Juan?

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Another question?

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AUDIENCE: What about if you--

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there's like a spaceship
goes to outer space,

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and they can see the
stuff in the way.

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If there's not visible
light, how they can detect

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there's stuff in the
way that's going to be

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danger for the space ship?

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MARK HARTMAN: OK.

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So you're talking about
like the dust in space

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that's close to Earth versus
the stuff that's way out there?

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AUDIENCE: Yeah.

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MARK HARTMAN: Well,
you kind of look at it

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with different tools.

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Juan's saying if we
go out into space,

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we need to know about
things that are out there.

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Remember, we're looking at this
really, really tiny spot that's

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near the sun, but
here we're looking

201
00:09:00,860 --> 00:09:05,150
at Cas A. This is already
a really far distance.

202
00:09:05,150 --> 00:09:07,341
This is 10,000 light
years-- we haven't talked

203
00:09:07,341 --> 00:09:09,590
about light years yet, but
it's the amount of distance

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00:09:09,590 --> 00:09:12,080
that light would
travel in one year.

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So this is really far away.

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00:09:13,950 --> 00:09:15,920
So we're looking at
different kinds of things.

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00:09:15,920 --> 00:09:18,800
The dust in the solar system is
kind of different from the dust

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00:09:18,800 --> 00:09:20,270
that we'd see in
between the stars.

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AUDIENCE: OK.

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MARK HARTMAN: OK.