Eclipses are significant experiences both from a scientific and a social perspective. When they happen, things can change. Such was the case with the solar eclipse that took place in 1919. This eclipse turned the world of math and science upside down and created a celebrity physicist named Albert Einstein who had his theory of relativity verified by the event.

Einstein’s shares his theory

Einstein debuted his theory of general relativity to the world in 1915 through four papers. The theory was initially met with high levels of resistance from the established scientific community who were focused entirely on Sir Issac Newton’s theory which was very different. How different? It is impossible to define all the specifics in a single article but a single example can make the point: while Newton’s theory described space as inert and unchanging, Einstein’s theory proposed that motions and objects in space can change and that these kinds of movement also interact with the dimension of time. Additionally, Einstein believed that currently accepted theories were oversimplified and didn’t fully express the complexities that were occurring. Another related example of the differences between each theory is connected to how they each believe that gravity affected light. The scientific community knew that if the effect of gravity on light could be properly measured it would prove that one, or the other, of the two theories were correct.

Proving Einstein was right during the 1919 eclipse

Several years after Einstein shared his theory the race to prove it (or disprove it) was well underway. To do so, scientists would have to measure the positions of background stars at the sun’s edge. Given the blinding brightness of the sun, this was no easy task but a solar eclipse could provide just the right conditions to make it happen because it naturally blocked out the brightest rays of light.

The total solar eclipse that proved Einstein’s theory was correct took place on May 29th.  It was viewed by two separate teams, one based in Brazil and the other an island off the western coast of Africa. Each team took measurements of the deflection of starlight off of the sun’s gravitational field. They were only able to see the starlight during the darkening of an eclipse because otherwise, the bright rays of the sun would make it impossible to see anything else. By the end of the eclipse, British astronomer Arthur Eddington was able to prove that the light rays of distant stars were pulled off of their paths by the gravitational field of the sun and that their movements were consistent with Einstein’s theory.

This particular total eclipse was perfect for the teams to use for measurements. Not only did it take place over a substantial amount of time leaving six full minutes of darkness, but its location meant that the sun would pass by a cluster of stars named the Hyades which would offer plenty of samples of starlight for the team to measure.

There was a chance the viewing might not have happened

Ultimately, the eclipse was one of the most important moments in modern science, but there was a strong chance of things not working out. Poor weather and cloudy skies could have blocked the eclipse in either or both locations and made it impossible to see what was happening or take measurements. Luckily, conditions were right and history, as well as the world of science, math, and cosmology were never the same since.

The world responds

Einstein waited in calmness for the results of the survey. As it turned out, this was a calm before the storm. When the official reports of the observations were released the following November, the world responded with enthusiasm and joyful headlines celebrated the triumph with headlines like “Light’s All Askew In The Heavens.” After the release of the news, Einstein became a celebrity and remained so through the rest of his life, becoming a leading icon of the 20th century. His theory has been verified additional times since, but at the same time, its full implications yet to be ascertained.

The eclipse experience a century later

This eclipse was considered often in history, and the world reminisced about it 98 years later when modern American audiences got to easily experience a total eclipse in 2017. Barring a cloudy day, this eclipse was expected to be seen throughout the greater part of the United States during the middle of the day.

While this experience didn’t lead to a substantive change in human understanding of mathematics and science, it remained exciting and culturally significant. The event connected a wide range of people with a common experience. Eclipse watchers reserved prime viewing spots months in advance, located Eclipse glasses, and became interested in what was happening in the heavens. When the day came they traveled significant distances, braving rush-hour like traffic, to be able to be in the zone of totality. As the eclipse happened, entire groups viewed it together, looking skywards and making sounds of amazement in the first moments the had an ultimate shared experience.

This same experience that enthralled people in 2017 had just as powerful an impact on the world a century earlier. As heavenly objects move in space, our observing it has the power to change things. Our understanding of the world, our assumption of our place in it, and our ability to appreciate forces larger than us may never be the same.