Black holes are among the most mysterious cosmic objects, much studied but not fully understood. These objects aren’t really holes. They’re huge concentrations of matter packed into very tiny spaces. A black hole is so dense that gravity just beneath its surface, the event horizon, is strong enough that nothing – not even light – can escape. The event horizon isn’t a surface like Earth’s or even the Sun’s. It’s a boundary that contains all the matter that makes up the black hole.
The Milky Way could contain over 100 million black holes, though detecting these gluttonous beasts is very difficult. At the heart of the Milky Way lies a supermassive black hole — Sagittarius A*. The colossal structure is about 4 million times the mass of the sun and lies approximately 26,000 light-years away from Earth, according to a statement from NASA.
How do black holes form?
Black holes are expected to form via two distinct channels. According to the first pathway, they are stellar corpses, so they form when massive stars die. Stars whose birth masses are above roughly 8 to 10 times mass of our sun, when they exhaust all their fuel — their hydrogen — they explode and die leaving behind a very compact dense object, a black hole. The resulting black hole that is left behind is referred to as a stellar mass black hole and its mass is of the order of a few times the mass of the sun.
Not all stars leave behind black holes, stars with lower birth masses leave behind a neutron star or a white dwarf. Another way that black holes form is from the direct collapse of gas, a process that is expected to result in more massive black holes with a mass ranging from 1000 times the mass of the sun up to even 100,000 times the mass of the sun. This channel circumvents the formation of the traditional star, and is believed to operate in the early universe and produce more massive black hole seeds..
Who discovered black holes?
Black holes were predicted as an exact mathematical solution to Einstein's equations. Einstein's equations describe the shape of space around matter. The theory of general relativity connects the geometry or shape of shape to the detailed distribution of matter.
The black hole solution was found was by Karl Schwarzschild in 1915, and these regions — black holes — were found to distort space extremally and generate a puncture in the fabric of spacetime.
It was unclear at the time if these corresponded to real objects in the universe. Over time, as other end products of stellar death were detected, namely, neutron stars seen as pulsars it became clear that black holes were real and ought to exist. The first detected black hole was Cygnus-X1
Did you know?
If you fell into a black hole, theory has long suggested that gravity would stretch you out like spaghetti, though your death would come before you reached the singularity.
But a 2012 study published in the journal Nature suggested that quantum effects would cause the event horizon to act much like a wall of fire, which would instantly burn you to death.
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