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This is an image of the Crab Nebula,
which is one of the most famous

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and most well-studied
astronomical objects ever.

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It's one of the touchstone images
from the Hubble Space Telescope.

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It's just the most beautiful,

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awe inspiring image you can imagine.

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Technically,
it's actually called a pulsar wind nebula,

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and we can connect it to events in history
going back to the year 1054,

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where Chinese astronomers

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recorded the appearance of a new star,
which they called a guest star.

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That got incredibly bright,
that you could see it during the daytime,

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which we now know
was a supernova explosion that was visible

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to the naked eye during the day for
about two weeks, maybe longer.

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What we're seeing here,
this filamentary structure

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is actually density variations
in that material.

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So as that material was spewed
from the star in the supernova explosion,

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it's still got the fingerprints
of that explosion.

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It's still expanding out
into the surrounding medium.

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So what we're able to see are
knots of material

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made up of things like oxygen, sulfur.

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And in this full color image,
the oxygen is coming out separately

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from the sulfur where the
the greenish, yellowish

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tinge is really oxygen heavy.

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Embedded in this nebula
is the pulsar at the center.

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And it's very energetic,

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so it's spewing out energy at all
wavelengths, actually.

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And some of that energy is being captured
by the material surrounding the pulsar.

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And then that material glows
and it glows in a certain wavelength

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or color, depending on what it's made of.

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So all the material that we're seeing here
is actually from the star itself.

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It's been blown out in that supernova
explosion,

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but it's being illuminated
by the pulsar in the center.

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Oxygen is

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such an important element of life
on the planet Earth.

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We are breathing in oxygen as we speak.

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Where did that oxygen come from?

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It came from the hearts of stars.

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They made the oxygen in fusion
and they expelled it

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back into the interstellar medium.

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We're actually watching that happen here.

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Maybe someday there will be a planet there
with an atmosphere that includes oxygen

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that can be breathed
by living organisms like us.