Why every picture of a black hole is an illustration – Vox

2019 update: The first image of a black hole: A three-minute guide.

No one has ever seen a black hole. There have been illustrations and computer simulations, but not even astronomers have seen a black hole… yet.

In the spring of 2017, we might see… something.

As a part of the Event Horizon Telescope project, nine (or more) synchronized observation stations around the planet will be focused on the Milky Way’s center. There, scientists believe we might finally see a black hole. From the BBC:

Supermassive though it may be, the heart of the Milky Way’s black hole is not as big as you might think; the event horizon of Sagittarius A* is just 24 million km across – 17 times bigger than the Sun.

At 25,000 light years away, that makes it a pinprick. From the surface of the Earth, Prof [Feryal] Ozel explained, it takes up about as much of the sky as a CD sitting on the moon.

And surrounding this mysterious, spherical frontier are roiling clouds of gas and dust, which blaze with energy as they are sucked and squeezed furiously towards it…

“Hopefully it will look like a crescent – it won’t look like a ring,” Prof Ozel said.

This is because the glowing gas is spinning around the black hole, and a dramatic Doppler effect should make the stuff moving towards the Earth appear much brighter. “The rest of the ring will also emit, but what you will brightly pick up is a crescent.”

Another reason that this black hole image will be a big deal: What we observe may predictably support or fail to comply with Einstein’s theory of general relativity.

Related reading: The Death of General Relativity Lurks in a Black Hole’s Shadow.