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"Inside the Hubble Image / M87 JET"

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This an image of something called M87. 

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M stands for Messier,
and Messier was an astronomer

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who was very interested in finding comets.

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But he didn't want to find duds.

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He didn't find false alarms.
This is one of them.

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And, you can see why

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if you were looking at something like that

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in a small telescope,
you might think it was a comet.

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And if we keep drilling down into why M87

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is such a fascinating galaxy,
it is an elliptical galaxy.

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And it's been known for quite a long time
that there was this little thing

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of brightness
that was spewing away from it.

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And now we know that
that's actually a jet of material.

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When Hubble was launched,
we had really good clues

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that galaxies
probably had black holes at their centers.

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So M87 does indeed
have a very massive supermassive black

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hole at its core on the 2 to 3 billion times
solar mass level.

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And that's a very massive supermassive
black hole, but it's also active.

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Why? So why are galaxies active?

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Not all galaxies are active.

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Just a few percent
are active at any given time.

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Are they turning on and turning off?
That's an idea.

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You know, maybe there's some
mechanical physics going on at the center

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of these galaxies where the black hole
has an accretion disk.

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And that material
is getting spun up so quickly.

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We know there's very high
magnetic fields that you launch a jet.

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And so this image is observational
evidence that what we've been seeing for

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a while
is actually being launched by a jet

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connected to that supermassive black
hole at the center of M87.

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What we're seeing here is one jet.

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So we can assume that this material here
that's making up the bulk of M87’s

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huge stellar
population is obscuring the other jet.

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In order to get a jet like that, you need
a magnetic field to accelerate particles.

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And you also need
a source of charged particles.

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So, that means that you need, near the core
of that galaxy, a disk of material

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and that that disk of material needs to be
spewing in towards the black hole.

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It's got a huge amount of gravity.
It's going to suck stuff in.

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And when it gets close enough,

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it starts to accelerate those particles
to ever increasing rates

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and then spews them out
along magnetic field lines.

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We've got lots of particles
and they are being accelerated

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at nearly the speed of light.

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The actual connection
between having a supermassive black hole

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an accretion disk and launching

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a jet is still one of the mysteries
of high energy astrophysics.

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How does that get launched?

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What is the actual physics between
the black hole, the disk and that jet?

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