Here’s the history behind the black hole
Apr 10, 2019, 3:15 PM
(Event Horizon Telescope Collaboration/Maunakea Observatories via AP)
This week, scientists revealed the first image ever made of a black hole in space.
Astronomers around the world held a major news conference on what was truly astounding.
Black holes have been in the news for well over 100 years, with German astrophysicist Karl Schwarzschild proposing there might be a region in space in which all forms of energy and light could not escape the gravity of the “black hole.”
A modern definition of a black hole might include a region of space time which exhibits a strong gravitational effect, in which nothing — not even particles and electromagnetic radiation, even light — can escape it!
The concept was even proposed by an English clergyman, John Michell, back in the year 1784.
He used the term “dark star” to introduce the concept of a star that would exist in space but not radiate “light,” as we know it in the conventional sense, due to the capture of photons by massive gravitational fields.
A further study into the origin of the term “black hole” goes to physicist Robert Dicke.
Dicke, in the early 1960s, associated the term with the black hole of Calcutta, a prison so bad that people went in but did not come out.
Astrophysicist John Wheeler of Princeton University also began using the term in lectures in the late 1970s.
The region that is at the outermost location of a black hole is known as the event horizon.
This boundary can be described as a boundary within in which the black holes escape velocity in greater than the speed of light.
Astronomers do know that there is a massive object at the center of our Milky Way galaxy, known as Sagittarius A. This is a powerful radio source and one that might be the location of a super massive black hole.
Astronomers with the new Event Horizon telescope have been building up strong evidence for establishing the first image of the event horizon of a black hole, silhouetted in front of the brighter core of the galaxy.
Here is a detailed graphic of the major components of a black hole:
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