Astronomers finally captured the primary image of a black hole, creating the revolution in people’s understanding of the most enigmatic objects of the Universe.
The image shows a halo made of gas and dust, tracing the colossal black hole’s outline at the center of the galaxy Messier 87, which is 55 million light years from our planet.
Black holes are cosmic trapdoors from which light or matter cannot escape – it is unseeable. However, observations from recently took the astronomers right to the threshold of black holes for the first time, illuminating the so-called event horizon behind which every physical law collapses.
This breakthrough picture was captured with the help of the Event Horizon Telescope or EHT, which is a network that is composed of eight radio telescopes which span locations from Antarctica to Chile and Spain, trying to involve over 200 scientists.
The Harvard senior research and director of EHT, named Sheperd Doelman, said:
Black holes are the most mysterious objects in the universe. We have seen what we thought was unseeable. We have taken a picture of a black hole.
The astrophysicist and also a director of US National Science Foundation, named France Córdova, said that this picture, which she saw only when it had been unveiled at press briefing which she has been chairing, made her cry.
We have been studying black holes for so long that sometimes it’s easy to forget that none of us has seen one. This will leave an imprint on people’s memories.
This image also gives the primary direct look of the accretion disc of the black hole, a fuzzy ring of dust and gas with the shape of a doughnut which steadily “feeds” this monster within.
The Event Horizon Telescope picks up the radiation which is emitted by particles which are within this accretion disc which are also heated to high degrees as they are swirling around the black hole, almost with the speed of the light, before they vanish down to the plughole.
The appearance of the halo in the picture, which looks like a crescent, is like that as the particles from the side of the disc which rotate towards the planet Earth, are also flung toward us faster, so that is why they appear brighter. The event horizon’s edge is marked with a dark shadow, and event horizon is actually the point of no return and the point beyond which there will not be a matter or light traveling fast enough in order to escape the extremely powerful gravitational pull that black holes have.
The Theory of Relativity of Einstein was the first that predicted black holes – even though Einstein was a bit skeptical that they existed. Since those times, astronomers accumulated immense evidence that such cosmic sinkholes exist, which includes the recent noticing of some gravitational waves which ripple all over the cosmos, when pairs of them also collide.
However, a black hole is small, distant, and dark, and observing it directly will require a telescope which has a resolution which will give you the ability to see a bagel on the moon. Once, this was believed to be a huge challenge.
With the combining of data from eight main radio observations in the world, which include the Atacama Large Millimetre Array or Alma, placed in Chile, and the South Pole Telescope, the EHT accomplished the needed firepower, and an effective and significant telescope was created, which had the Earth’s size.
With the launching of the observations in 2017, this Event Horizon Telescope had two main targets. The first one was a black hole known as Sagittarius A*, found and the Milky Way’s center, while the second one was the supermassive black hole found in the galaxy M87.
The collaboration still works on producing the picture of the black hole located in the Milky Way. The volume of the data collected was unprecedented too – in only one night, this telescope collected data which could fill half a ton of hard drives.
The observations already give scientists some new insights about what happens in the environment near black holes. The observations even provide one of the most stringent tests to date of the Theory of General Relativity of Einstein. This, in fact, predicts that the halo of a black hole has rounded shape.
Scientists even hope to understand something more related to the origins of the radiations jets, broken apart from black holes’ poles almost at the speed of the light, creating some brilliant beacons which may be picked out all over the cosmos.
But, the observations still don’t reveal anything related to the inscrutable interior of black holes.
One member of the EHT collaboration based at University College London, named Ziri Younsi, said:
The black hole is not the event horizon; it’s something inside. It could be something just inside the event horizon, an exotic object hovering just beneath the surface, or it could be a singularity at the center… or a ring. It doesn’t yet give us an explanation of what’s going on inside.
The chair of the science council of EHT, named Heino Falcke, based at the University of Radboud, Netherlands, also said that one big question for him is if they will have the ability to transcend the limit. In fact, the answer can be negative. He said that such an answer would be frustrating, but they need to accept it.