General Relativity and the Discovery of Black Holes.

Publication of Isaac Newton's Mathematical Principles of Natural Philosophy

Jul 5, 1687

Introduced laws of motion and universal gravitation.

Dark Stars

Mar 13, 1783

John Michell proposes the concept of “dark stars" in which he suggests that a star could be so massive that light could not escape it. This was an early theoretical prediction of something like a black hole, based on Newtonian gravity.

Discovery of Neptunes

Oct 13, 1846

Neptune was discovered based on gravitational irregularities through observations of Uranus' orbit variations using Newtonian laws of gravity.

A Dynamical Theory of the Electromagnetic Field

Sep 20, 1865

James Clerk Maxwell publishes “A Dynamical Theory of the Electromagnetic Field." Maxwell’s equations unified electricity and magnetism and implied that light travels at a constant speed, an insight that challenged classical mechanics and influenced Einstein’s thinking.

Publication of Einstein's paper on special relativity.

Jun 30, 1905

Laid out the foundation for his future developments of general relativity.

Einstein provides a new description of gravitation as the curvature of spacetime.

Nov 25, 1915

Einstein presents the field equations of general relativity to the Prussian Academy of Sciences.

First experimental confirmation of general relativity

Jan 1, 1935

Sir Arthur Eddington observed the bending of starlight by the Sun's gravity during a solar eclipse.

First identification of a black hole

May 16, 1964

Cygnus X-1, a black hole candidate was found through X-ray observations.

First image of a black hole is released

Apr 10, 2019

M87, a distant black hole becomes the first visual confirmation of black holes predicted by general relativity. Captured by the Event Horizon Telescope.