This is the Nature Pastcast, each month raiding Nature's archive and looking at key moments in science.

The first World War is drawing to an end and a team of astronomers hatch a plan to chase a solar eclipse across the globe

in order to test Einstein's bold new theory. Nature.

November the 13th, 1919, results of the solar eclipse of May 29th and the relativity theory.

The May 1919 eclipse was one of the first opportunities anyone would have to really

in check and see whether Einstein's ideas were correct.

Just on the heels of what had been this horrible, horrible conflict between Britain and Germany,

among others.

Here was a British team led by a Quaker, pacifist, internationalist,

mathematical physicist, eager to restore what he called the Brotherhood of Science.

Einstein becomes famous essentially overnight

because the expedition was so dramatic and so exciting in such an extraordinary way to think about science being done.

My name is David Kaiser. I'm an historian of science and a physicist, and I teach at the Massachusetts Institute of Technology.

1918, from a speech by Arthur Eddington to the Royal Institution,

Gravitation and the Principle of Relativity.

Arthur Eddington was a remarkably gifted astronomer and mathematical physicists in a way that that was not always the case.

People by that point had often specialized in one or the other, and Eddington was remarkably

talented across the board. And he was very deeply interested earlier than almost anyone,

certainly in Britain, deeply interested in this new, not well-understood work by Albert Einstein

on what came to be known as general relativity.

So a generalization 10 years on from Einstein's special relativity.

So Eddington had a special and unusual interest in Einstein's work.

...