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First Image of a Black Hole!

This is the first-ever image of a black hole released by the Event Horizon

Telescope collaboration on April 10th 2019

It shows plasma orbiting the supermassive black hole at the center of

the galaxy M87. The bright region shows where plasma is coming towards us and

since it's traveling near the speed of light it appears brighter when coming

towards us and dimmer when going away. This is called relativistic beaming.

From the images scientists can tell that the plasma is orbiting clockwise. It takes

around 2 days for the plasma to complete one orbit. Here we are looking at the

black hole using electromagnetic waves with a wavelength of 1.3 millimeters -

radio waves. This was the part of the spectrum used to make the image because

it can show us the features close in to the event horizon and it can pass

through the accretion disk and interstellar dust to reach our

telescopes. The supermassive black hole in M87 is very active meaning it's

constantly feeding on lots of matter from its glowing hot accretion disk, but

it also has narrow collimated jets above and below it here shown in blue, thought

to be created by incredibly strong magnetic fields. The jets extend out at

least 5,000 lightyears and one of them appears to be pointing almost straight

at us. Relativistic beaming is again the reason

we can see the jet coming towards us in this Hubble Space Telescope image but

not the one going away. Since the jet is pointed almost straight

at us I'm thinking our perspective is almost perpendicular to the accretion

disk but let's have a look at what we would see if we were looking at

different orientations. The warping of space-time around the black hole means

we can see light even from parts of the accretion disk behind the black hole.

They are lensed above and below the shadow region.

Not gonna lie this is so trippy I

could stare at it for a long time. So the big question most people are going to be

asking is why is the image so fuzzy?

The answer is because it's so tiny.

Don't get me wrong the black hole itself is huge, supermassive in fact. As measured

from this picture the black hole has a mass 6.5 billion times that of our Sun.

The actual size of its shadow is nearly the size of our solar system, but located

fifty three and a half million light years away its size from our perspective

is only about 40 micro arcseconds - that's the angle it makes on the sky.

To understand what that means take the whole sky and divide it into

180 degrees. Then divide a degree into 60 arcminutes and an arcminute into 60

arcseconds. Divide an arcsecond into a hundred

and into a hundred again

and into a hundred once more and that is the size of the black hole shadow only about

40 micro arcseconds. It puts us at the very limit of what we are

technologically capable of seeing. In fact to get this sort of resolution due

to the basic law of physics the diffraction limit we needed a telescope

the size of the Earth. That being impractical the scientists used eight

telescopes spread across the globe. They all simultaneously observed M87 and as

the earth rotated that helped fill in the earth-sized telescope that they were

trying to simulate. But M87 was not the only black hole they looked at. They also

observed the supermassive black hole at the center of our Milky Way galaxy,

Sagittarius A* - they haven't yet release an image of this black hole, but this simulation shows what it might look like.

it's much closer at around 26,000 light years away but also

much smaller with a mass only four million times that of our Sun. It's also

less active, only periodically gobbling up matter, and it would have much more

variation over time with matter orbiting every four to thirty minutes.

That's probably why we'll have to wait a little longer to see the black hole at the center of our galaxy.

For now, the striking image of the black hole in M87

confirms beyond a shadow of a doubt that black holes do exist.

The general theory of relativity published over a hundred years ago is supported again in

spectacular fashion in the strongest gravities and

at the limits of our ability to test the theory.

What I love about moments like this

is the ridiculous extreme things these scientists did

these 200 scientists in pursuit of a goal that seemed impossible and yet they achieved it.

I want to extend my personal congratulations to everyone on the team

for an amazing discovery. I'll be linking to all their work in the description