For most people, the name Georges Lemaître probably doesn't ring any bells. Yet Lemaître –Belgian Catholic priest, WWI military hero, theoretical physicist, mathematician, astronomer, and professor of physics –- was one of the most influential scientists of his generation.

Born in 1894, Lemaître was a pioneer in offering a new conception of the cosmos, in a career that spanned the better part of forty years. Prior to describing his idea of "the Big Bang theory," he used terms like "cosmic egg" or the "primal atom theory." Equally impressive, Lemaître was also the first to theorize that the recession of nearby galaxies can be explained by an expanding universe. This breakthrough led to him publishing the first estimation of the Hubble constant in 1927, two years before Hubble's historic article.

Parallel to his scientific career, Lemaître pursued an ecclesiastical career in the Catholic Church. After completing his theological studies, he was ordained an abbot in 1923, and later attained the rank of President of the Pontifical Academy of Sciences in Rome. In addition to serving as a personal adviser to Pope Pius XII, Lemaître published several theological works during his extremely prolific lifetime. Before his death in 1966, he received numerous honors and awards from science organizations around the globe.

In 1924, Lemaître traveled to the U.S. to study at the Harvard College Observatory and enroll in MIT’s PhD program in physics. At the time, Harvard did not offer a graduate program in astronomy, but MIT proved to be all that Lemaître could have hoped for, as it gave him the opportunity to meet the world's leading astronomers and learn about their discoveries. These luminaries included Edwin Powell Hubble and Harlow Shapley, whose works convinced Lemaître that the universe was in a plane of expansion.

While studying at MIT, Lemaître also learned the latest velocity and distance measurements for the newly found "spiral galaxies." Access to these state-of-the art observatories was critical to his work. Having visited Shapley at the Lowell Observatory, and Hubble at Mount Wilson, Lemaître began to work on a new cosmological model, in which space-time continually stretches, and galaxies surf outward on the wave. However, he had not fully developed his new cosmological model by the end of 1925, when he handed in his doctoral thesis, "The gravitational field in a fluid sphere of uniform invariant density, according to the theory of relativity." In 1927 he successfully defended his thesis, earning a PhD in Physics. More importantly, Lemaître laid the groundwork for his historic "Big Bang theory" while studying at MIT.

In 2009, the Belgium scientist was the focus of a feature article in the MIT Technology Review, a world-renowned publication that was founded at MIT in 1899. The article, which was titled "Before the Big Bang," does more than highlight Lemaître's wide-ranging legacy in science. The article also draws special attention to the importance of his days as a graduate student at MIT, which has served as the setting for so many scientific breakthroughs over the years. "The idea that the universe is expanding was one of the most revolutionary and unsettling findings of modern astronomy. But the discovery was not made by Edwin Hubble at the Mount Wilson Observatory in California in 1929, as so many textbooks suggest. The germ of the idea actually arose in the halls of MIT and Harvard, a few years before Hubble initiated his historic measurements of galaxy motions. It hatched in the mind of a Jesuit priest then studying at the Institute’s physics department."

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