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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.

  • Wait what? That can't be right.

  • The black hole in question is M87*,

  • 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 raycoming 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.

  • How fast was the material moving?

  • 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 onsomething 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.

  • Still, the material is really shifting.

  • 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.

In April of 2019, astronomers revealed they had successfully taken the first picture ever of a black hole.

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この巨大なブラックホールは、光速の99%の速度でジェット機を爆破しています。 (This Massive Black Hole Is Blasting a Jet at 99% the Speed of Light)

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    林宜悉 に公開 2021 年 01 月 14 日
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