Black Holes

Black holes were foreseen in 1783, John Michell postulated that an invisible star could be massive enough to trap light, so called Dark Stars. The idea, expressed only in a Royal Society letter, remained largely unconsidered for a decade.
In 1798, Henry Cavendish, using lead spheres and carefully recorded observations, determined the gravitational constant and the weight of the world. He placed the density of our rock at 5.45 times the density of water, a number that matches well with today’s estimation of 5.51. Cavendish’s calculations of Total Mass were also pretty accurate, 5.97 × 10²⁴ kilograms.
Cosmologists pondered those speculations for 100 years until 1915 when Albert Einstein published the theory of general relativity, predicting spacetime and gravitational curvature or warpability.
A 19-year-old mathematician named Chandrasekhar mathematically proved a star just 1.4 times solar mass (the mass of our sun) will collapse. In 1939, Oppenheimer predicted at a collapsing star, provided it retained enough mass, would collapse all the way down to a black hole.
Back in 1916, Karl Schwarzschild had predicted a flat black hole without charge. Such a black hole probably does not exist. If it exists, a single proton striking it off-center would impart the customary spinning rotation. In 1963, Roy Kerr published the Kerr solution which correctly painted the more correct picture of a violently spinning monster pulling everything inward.
In 1971, the first black hole, Cygnus X-1, was first spotted. Stephen Hawking famously played the devil’s advocate and lost a bet as to whether Cygnus X-1 actually was a black hole. Cygnus X-1 is about 21 solar masses and is 7,000 light years away in the northern sky.
Super-massive holes, like Sagittarius A at the heart of the Milky Way, first came into view via the Hubble Space Telescope in 1994.
Be thou aware! We are on the precipice of some amazing revelations.