Name: 這個巨大的黑洞正以99%的光速噴射噴氣式飛機。 (This Massive Black Hole Is Blasting a Jet at 99% the Speed of Light)
Uploaded: 2021-01-14T10:46:37.000Z
Duration: 4 min 50 s
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In April of 2019, astronomers revealed they had successfully taken the first picture ever of a black hole.

Well, you know, the black hole's silhouette at least,

since it's impossible to take a photo of a black hole itself

without crossing the event horizon and getting spaghetti-fied.

Now, astronomers have announced that the same black hole has been observed

shooting jets of physical material out into space at insane speeds...

and at first glance, it looks like that material is traveling even faster than the speed of light.

the supermassive black hole in the center of the enormous elliptical galaxy Messier 87.

M87* is roughly 55 million light-years away

and absolutely dwarfs our own galaxy's supermassive black hole, Sagittarius A*.

While Sagittarius A* is about 4 million solar masses, M87* is in the neighborhood of 6.5 billion solar masses.

And from where we stand it looks like it's getting bigger.

That glowing orange halo in the famous photo represents superheated gas and dust

that's orbiting and feeding the black hole.

This is what's known as an accretion disk.

Some of that matter will fall into the black hole,

but some of it gets shot off into space in the form of jets spewing from the poles of the spinning black hole.

We've known for some time that M87* has these jets streaming from its poles.

It was as far back as 1918 when one astronomer first noted a “curious straight ray” coming from the galaxy.

More recently, the Hubble Space telescope took multiple images in the infrared and visible light spectra.

The composite photo shows a striking blue beam extending as far out as 5,000 light years

against the yellow glow from the combined light of billions of stars.

Knowing M87* is an active black hole with matter falling into it is actually one of the reasons

astronomers picked it as their target to photograph,

unlike Sagittarius A* which is closer, but obscured by the stars and dust in our own galaxy.

So yes, we've taken pictures of M87*'s jet of matter before, but this is the first time

scientists have observed it in the X-ray spectrum in such fine detail.

X-ray light confirms that what's moving at extreme velocities in the jet is actually physical material,

as opposed to something else, like shock waves.

Well, the material isn't shot off in one continuous beam,

but rather in clumps...like bubble tea through a straw.

The astronomers observed a clump farther along in the beam traveling at 2.4 times the speed of light,

while another mass of matter closer to M87* appeared to be moving at 6.3 times the speed of light.

But hold on—something doesn't add up here.

We know for a fact that these clumps we're looking at are solid matter thanks to the X-ray imaging,

and we also know that nothing with mass can travel the speed of light, let alone multiple times faster.

Well, it turns out those ludicrous speeds are a product of an optical illusion.

the angle the jet is being shot towards us and the material's extreme speed

produces what's called superluminal motion, but really no laws of physics are being broken.

Taking the illusion of superluminal motion into account,

the researchers still estimate sections of the jet of matter are traveling at over 99% light speed.

They think that the material gets funneled up to the poles of the rotating black hole

and shot out by following its twisting magnetic field lines.

The blue glow is generated by electrons traveling along the spiral path, a process called synchrotron radiation.

Now, I'm sure some of you may be disappointed to learn

that the material isn't actually traveling at over 6 times the speed of light.

There goes our hopes of faster than light travel.

But the dreamers and optimists among you may hear that supermassive black holes

still accelerate matter to over 99% light speed and think that sounds like a pretty good deal.

Maybe you're thinking we could harness it for space travel one day like a Mass Relay in Mass Effect.

Just remember though that material was only shot out at those great speeds after becoming superheated

and turned into plasma by the friction of other matter swirling around the accretion disk.

So, while M87* and its jet of matter may make for good sci-fi fodder,

it's probably best to admire it only in pretty pictures.