On 29 May 1919 there was a total eclipse of the sun that was visible in the southern hemisphere. A team of scientists with specially filtered telescopic cameras documented the event. What was super special about the cameras, apparently, was that the films showed not only the rim of the sun but also stars around the sun.
The stars weren't in their predicted positions.
This is the etymological essence of a "disaster": dis + aster (star). The appearance did not match the expectation.
Once that news came out, it was more widely accepted in the astronomy / physics community of scientists that the "unprovable" theory of a 40 year old German-born mathematician / physicist was demonstrably true. Albert Einstein's theory of relativity was fact, not just weird math. Light had been seen to have bent in the gravitational field of the sun.
So it is that 30 May is considered the "birthday" of general relativity. Oh the theory had been alive and kicking in the womb of mathematics since 1905, in all the glorious beauty of the Lorenz transformation, but 30 May is when it came out singing the praise of the Creator.
Space-time ain't flat.
But I'm still waiting for artificial gravity -- and anti-gravity!