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At first glance, this single bright source,

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this smudge,

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this grouping doesn't look like much.

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Images like these are translated
for our eyes, and it's because our eyes

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only can perceive a small region
of all the frequencies of light.

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Astrophysics is much

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more than just capturing
different wavelengths of light.

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Many objects or phenomenon are simply too

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far away to directly image.

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A lot of data comes from pixel-sized

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point sources, and those points provide astrophysicists

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with a powerful window
into what makes up the universe.

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Even now,

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most of what scientists learn about
the cosmos

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comes from studying light.

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Astronomers can work out distances,

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speeds, sizes, temperatures
and the composition of elements

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because matter behaves in predictable
and consistent ways.

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They do this
by literally prying these photons apart.

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This is spectroscopy, explained

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Spectroscopy

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is a study of how matter interacts
with light, and it all began

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with a prism like this one.

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Light entering
one side of the prism bends, or refracts,

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as it passes through the triangle
shape and exits out the other side.

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All of the wavelengths enter together,

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but they exit as a rainbow-like spread of colors.

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What's happening is that the shorter,

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more energetic wavelengths
like blue and violet

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bend a little more than the longer, lower-energy light
like red and orange.

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Because they bend at slightly different
angles,

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the wavelengths separate,
fanning out into a band of colors.

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NASA has a whole fleet of telescopes
that can split and study

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a wide range of light
on the electromagnetic spectrum,

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not just the light
that our eyes can detect.

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So Hubble
can detect through the visible spectrum,

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but also a bit into the infrared
and the ultraviolet.

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Webb is just infrared
and can look at the light

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that is emitted
from billions of years ago.

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And of course, the images from Webb
are really spectacular.

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But this is what flutters
the hearts of scientists.

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This spectrum shows
the light that penetrated the atmosphere

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of a planet called WASP 96 b.

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The light being measured
comes from the planet's host star,

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some of which skims
through the atmosphere.

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Humans are a long way from directly
imaging exoplanets,

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so telescopes
like Webb will use spectroscopy

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to find those chemicals that could support
life in their atmospheres,

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which is why Webb's
first spectra is so amazing.

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You're actually seeing bumps and wiggles
that indicate the presence

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of water vapor
in the atmosphere of this exoplanet.

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Incredible.

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But it's one thing to identify
single elements or simple molecules,

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but deciphering whole foreign bodies
like Dr. Ogorzalek ...

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How do you know?

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Oh, it took us a very long time
to figure this out.

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It really took us many, many decades,

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and it took us, many, many fantastic
new instruments.

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If all of our astrophysical objects
or anything they were looking at

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were made up of one element,
this would just be so easy.

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But we don't.

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So we have to do experiments on Earth
like this to prove what we're looking at.

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Looks like what we are thinking
we're looking at.

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So in here is argon.

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If we turn it on here, it glows

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this really pretty purple.

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And then if we look at it
with a spectroscope,

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it shows us a very specific fingerprint
to argon.

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These are called spectral
tubes.  My bounty of tubes.

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They contain the gas of one element,

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and the box runs a voltage
through the tube.

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When I turn on the switch,
the charged gas turns

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to plasma and emits a color
that is unique to that one element.

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It also makes unique lines
when you look through the spectroscope.

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And this one is helium.

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This same process happens in a
star or a hot region of gas.

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So we use tubes like this

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to verify what we see in space.

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If you do a quick search for spectroscopy
data,

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there are numerous ways
that the data can appear.

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Those variations are based on
the source of the cosmic light.

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There are three types of spectra
that we can use.

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Continuous, emission, and absorption.

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Light from a hot, dense source,

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like the Sun, produces
a continuous spectrum.

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When that light passes
through cooler gases on its way to us,

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the gases take away or absorb
some of that energy.

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Dark lines appear where specific

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colors are missing,

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And when thin gases glow themselves,

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we see only their characteristic colors.

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Kind of like a cosmic barcode.

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These are the emission spectra
from pure elements

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that were given a voltage to glow
just like my spectra tube, but way better.

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Like all data,

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there is an art to analyzing spectra.

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Scientists like Dr. Ogorzalek

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use computers to calculate
and tease out clear signals,

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comparing them then to models
that are already known.

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Many scientists in the labs on Earth,

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they tried to recreate the same conditions
and measure basically what these

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kind of, as you said, fingerprints
of those different transitions

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for different elements are.

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Okay,

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so we're always comparing to sort of
the fingerprint of what we have,

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and then if it has deviated from that,

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that is the new information
from what we're looking at.

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Correct.

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For Anna, spectra unveil
the structures of black holes,

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the swirling winds that surround them,

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and those big jets of particles

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that come out of them.

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When you look at a black hole ...

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Yes.

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... this is what you see.

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Yes.

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Where, where is the accretion disk?

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Where are the winds?

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So all of this is mostly accretion
disk at this level.

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It's just different
parts of it. We can zoom in, right?

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And we see all of the absorption lines, right?

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All of these lines are also shifted a lot.

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So they come from this wind
that we saw in the in the first picture.

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So that's how we know that there is winds
blowing around black holes.

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The same principles apply
no matter the wavelength of light,

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but each wavelength of light
tells us a little something different

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about each character
we find in the universe.

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It's pretty wild how different

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the universe looks to our eyes
and how it presents to our telescopes.

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And that's precisely why we need to
observe in different wavelengths of light.

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Modern astronomy is built upon spectroscopy.

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So with every stream of light we gather,
we further

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understand what the universe is made of.

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All we need to
do is pry open its contents.