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This is an image of

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Eta Carinae taken with the Hubble Space Telescope.

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And there's a lot going on in this image.

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If you go down
into the very center of this image,

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you can see this bright spot here
that's actually two stars, much,

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much more massive than the sun
that are in orbit around one another.

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So what you see here
are these two lobes of material,

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and they are from a giant eruption
that the star had about 200 years ago.

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And when these massive stars are near
the end of their life,

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they become quite unstable.

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And there was this tremendous eruption
that blew off about 20 times

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the mass of the sun.

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And there was a massive brightening
of the star, became

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one of the brightest stars
in the sky in the 1840s.

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And what we see here is the result of that

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massive eruption
and these lobes of material

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that are slowly making their way out
into interstellar space.

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Mariners at the time used it
as a navigation aid, but this brightening

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only lasted a number of years
and it since faded.

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But Eta Carinae is still
a relatively bright star.

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The dust in this

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homunculus nebula, which is what it's
called, is going to continue to expand.

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It's being illuminated by the stars
that are interior to it.

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Here's another image of Eta
Carinae taken with Hubble.

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It looks a little different.

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Hubble is outfitted
with very specialized filters that can see

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the light emitted from specific atoms
at specific wavelengths.

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The blue shows you
where the magnesium is emitting light.

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The red shows regions
where nitrogen is emitting light.

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They have different ionization states.

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They respond to this ultraviolet light
in different ways.

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One of the things that happens

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in these massive stars
is they're factories for heavier elements,

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and that's where the heavy elements
in our bodies on the earth all come from.

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Stars like this supernova and massive stars

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that process them and eject
the material back out into space.

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And that's sort of the hard work
that astronomers want to do because we

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want to understand all the details
of what's happening in this nebula.

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That's what these extraordinary eyes
that Hubble has allow us to do.

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This is
a very complex and volatile object.

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And in fact,
one of the reasons for being interested

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is that on the list of stars
that we know about in the Milky Way,

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that may soon become supernovae,
this is one of them.

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It takes about 8000 years
for the light from Eta Carinae to reach us.

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And so it could already have gone supernova

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8000 years ago and we wouldn't know it.