Einstein’s theory of gravity was tested 100 years ago tomorrow, but what may be less well known is the Irish connection with this seminal event.
On May 29, 1919, a total eclipse of the sun provided the first evidence to support Albert Einstein's theory of general relativity, explains Professor Paul Callanan, a Physicist at University College Cork (UCC).
A few years earlier, Einstein had predicted how matter could bend the space around it, generating what we experience as gravity.
It was decided that the sun would be photographed during an eclipse in order to test this hypothesis and to see how the light from distant stars was affected as it passed as close as possible to the sun.
This was the time to shine for an Irish astronomer and instruments made in UCC.
Two expeditions set off from England to gather images of the sun during the eclipse - one to an island off the coast of Africa, and the other to a town called Sobral in Brazil.
Prof Callanan outlines how it transpired that the most accurate measurements were taken in Sobral using the instruments made in the Crawford Observatory in UCC by Howard Grubb.
The mission was led by a Co Antrim astronomer, Andrew Crommelin from Cushendun.
Einstein became a household name once the results of the experiment were released, and, according to Prof Callanan, it was "one of the defining moments in our understanding of how gravity really works".
The findings made the front page of the New York Times with the headline: “Lights all Askew in the Heavens, Einstein Theory Triumphs”.