Shapley, Harlow

Shapley, Harlow Wright, Helen and Rapport, Samuel. Readings in the Physical Sciences. Appleton-Century-Crofts, Inc., New York. 1948. 

Shapley, Harlow (1943) Samuel Rapport and Helen Wright, A Treasury of Science, p. 435, Harper and Brothers, New York and London. 

By identifying Cepheid variables in the globular clusters which gravitate around our own Galaxy, Harlow Shapley was able to measure their distance. He thus located their common centre and found it to be a considerable distance from us. It was clear that human beings inhabit the neighbourhood of a nondescript star, very far from the centre of the Milky Way. We are not even at the heart of our own stellar republic A second assault was thus made on human vanity, after the eviction of the Earth from the centre of the Universe. 

Payne was born in 1900 in Wendover, England, to an upper-class family. Her early education was in botany, physics, and chemistry, but her passion was astronomy. In 1922, she heard a lecture by Harlow Shapley, the director of the Harvard College Observatory. The lecture inspired her to seek admission to Harvard, and with strong recommendations from her mentors in England, including Sir Arthur Eddington, she was admitted and arrived on campus in 1923. Two years later, in 1925, she became the first student, male or female, to earn a Ph.D. from the Harvard College Observatory. 

If God did create the world with a word, the word would have been hydrogen, said Harlow Shapley, one of the twentieth century s greatest astronomers. In our current theory of the origin of the universe, when atoms first formed out of the sea of particles created in the big bang, basic hydrogen—one electron and one proton— constituted some 92 percent of the atoms, while virtually all of the rest was helium. Today, some 15 billion years later, about 90 percent of all particles are hydrogen and 9 percent are helium.2... 

If God did create the world by a word, the word would have been hydrogen. —Harlow Shapley... 

In 1917 Harlow Shapley mapped the extent of the galaxy by counting globular clusters rather than stars. Globular clusters are collections of roughly 100,000 stars. They can be seen from the distant reaches of the Milky Way. Just as Copernicus before him concluded that Earth is not the center of the solar system, Shapley proved that the solar system was not at the center of the galaxy. Since Shapley s time, astronomers have refined his technique and discovered new ways to deduce the size, structure, and contents of the Milky Way. 

Recently, I wanted to refer to an account of some calculations made by Harlow Shapley, the eminent American astronomer, which showed very clearly the huge number of molecules in any small parcel of matter. The story was based on the fact that in any volume of air, four fifths of the particles are molecules of nitrogen and that when a deep breath is exhaled, the nitrogen molecules in it are rapidly dispersed. After a certain period, probably not more than a few years, perhaps less, they will be equally distributed throughout the atmosphere. By this time, each unit volume of air at the surface of the earth will contain between two and three of the nitrogen molecules that were present in the original volume exhaled. To make it more dramatic, the author of this account selected the breath that Shakespeare exhaled as he wrote the first line of the second act of Hamlet. As you inhale a breath today it will contain two of the actual molecules exhaled by Shakespeare at that particular moment. You would be most unlucky were you to get only one molecule were you to capture three, you would belong to a fortunate minority. 

Prom his observations William Herschel (1738-1822) concluded that stars in the Galaxy were distributed in a disc-like strnctnre, centred on the Sun. It remained the accepted picture until early in the twentieth century, when, based on the study of globular star clusters, Harlow Shapley proposed (1912) a disc-like Milky Way surrounded by a spherical arrangement of clusters and... 

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