Black hole

This Wednesday 10/04/2019 is a historic day for science, space and for all humanity: the first image of a black hole in history is revealed.
What is a black hole?
A black hole is a celestial object that has an extremely important mass in a very small volume. As if the Earth were compressed in a thimble or the sun only measured 6 km in diameter, recently explained to the AFP agency Guy Perrin, astronomer of the Paris-PSL Observatory
It should be noted that you have never seen a real image of that phenomenon, since black holes are literally invisible and absorb all electromagnetic radiation, so none of the telescopes available to mankind (whether radio, lightning X, optical or gamma) can detect them.

"Theoretically it is possible to see its event horizon, the point beyond which even light can not escape due to the intense gravity of the black hole.
Nothing inside can live and be transmitted abroad (...). You can not see a black hole, but you can see its shadow, which occurs when the light disappears behind the event horizon (of the hole), "explained the chairman of the Event Horizon Telescope, Heino Flacke.