RAS Hosts Urey, Shapley, and Gamow

By Stephen Tzikas, Class of 1983

Over the decades, Rensselaer Polytechnic Institute (RPI) was host to some of the greatest astronomers. Those who visit to the Hirsch Observatory will notice three framed vintage announcements hanging in the main foyer. Any student or well-versed reader of astronomy will immediately recognized the names of these three giants of early and mid 20th century astronomy. They are Harold Urey, Harlow Shapley, and George Gamow. Dr. Urey was one of the fathers of astrobiology. Dr. Shapley was first to estimate the size of the Milky Way and develop the concept of a solar system habitable zone, while Dr. Gamow was a theoretical physicist and cosmologist, as well as an immensely popular author of layman science books. Records of RPI's rich astronomical tradition exist if one is willing to do a little research. Events such as the visits of these famous astronomers to RPI were events big enough to be recorded in the local newspapers, as these astronomers were household names in their time.

A visit to the Troy Public Library microfiche collection will allow one to read the original article in which Dr Urey criticized Senator Joseph McCarthy in an exclusive interview with the Troy newspaper, while in Troy to deliver a lecture at RPI. Dr. Urey, who won the 1934 Nobel Prize in chemistry for his discovery of heavy hydrogen, died in 1981. Colleagues considered that Dr. Urey founded modern lunar science with his speculations and deductions about the Moon's geology. In 1953, Dr. Urey carried out a landmark experiment demonstrating that Earth's primordial ingredients could have been forced by lightning discharges to combine into some of the basic chemicals of life, specifically four amino acids, the building blocks of protein.

The Rensselaer Astrophysical Society (RAS) hosted Dr. Urey on the evening of January 12, 1954, when he spoke before a large RPI audience about his theory on the Moon's surface and the origin of the Earth. The greater part of Dr. Urey's speech dealt with technical matters of interest to the more than 200 students in attendance. The speaker observed that on first glance the Moon appears as a sphere of craters as seen through telescopes and in photographs. "It is only after considerable study that the craters and other features of the Moon assume any meaning for the researcher," the doctor said. In discussing the rugged contours and composition of the Moon, Dr. Urey accentuated his remarks by the use of slides. He discussed various theories concerning the Moon's origin and its surface geology. Dr. Urey theorized that the Moon's craters are the results of collisions of objects with the Moon, and possibly could also be the result of volcano eruptions. Dr. Urey cited several technical factors and hypotheses to bolster his beliefs. "The whole process of forming the Moon's surface took place in a relatively short space of time," said Dr. Urey. Dr. Urey noted that his Moon theories were influenced by those originally presented by Dr. Grove K. Gilbert in an 1893 research paper. Concluding his lecture, Dr. Urey presented the hypothesis that the Earth was formed at a much lower temperature than that generally accepted by scientists of that time. To substantiate the theory, he stressed the fact that if the Earth had been formed at a very high temperature, certain relatively volatile substances, (As, Hg), would be more abundant near the Earth's surface. Dr. Urey had also toured the University and noted, "The research going on in your chemistry department, particularly that conducted by Drs. Harteck and Dauer, interests me very much." While at RPI he again noted the activities of Senator McCarthy and the negative impact they had on scientific research. This was Dr. Urey's second visit to RPI, the first being in 1934, just a few days after he was awarded the Nobel Prize in chemistry. The Poly also covered this first visit, where Dr. Urey spoke of his work in the study of isotopes at the second Sigma Xi meeting of the year at the Russell Sage Lecture Hall. Dr. A. W. Bray, Professor of Biology and President of the RPI chapter of Sigma Xi, introduced Dr. Urey, one of his former students, to a large audience of students, professors, and businessmen of Troy, Albany, and Schenectady.

On Thursday, March 24, 1955, the President of the RAS, Stephen W. Closs Jr., presented the noted astronomer Dr. Harlow Shapley of Harvard University. The Troy Time Record included a photograph of the event. Dr. Shapley lectured on the known formation of stars and galaxies. Dr. Shapley, speaking in the lecture hall of Sage Laboratory, was heard by an audience of 125 RAS and Troy Astronomy Club members, as well as many other RPI students. "A third of the entire sky, including the belt of stars called the Milky Way, is so filled with cosmic dust that distant galaxies of stars are concealed from the view of astronomers," Dr. Shapley said. "It is from such cosmic dust, it is currently surmised, that stars were born and are being born," Shapley continued. He discussed his current research in the measurement of the opacity of the cosmic dust clouds in the southern Milky Way. It is behind some of these clouds of dark interstellar material that, many years ago, he located the center of the galaxy. It is around this central nucleus made up billions of stars, about 27,000 light years from the Earth, that the Sun and the "naked eye" stars revolve, Dr. Shapley said. Dr Shapley spoke about other areas of his research such as the Magellanic Clouds. His Harvard Observatory had developed photographs of galaxies so distant that the light now being received has been en route for a billion years, he said. Dr. Shapley's talk was supplemented by numerous slides to illustrate his topics. Additionally, he discussed the significance of modern observing instrumentation, noting that the Mt. Palomar telescope has photographed galaxies probably 2 billion light years out in space. "What is beyond these, no one knows," Dr. Shapley said. Whether the Universe is finite or indefinite remains an unsolved problem for astronomers and philosophers. In the half-century since Dr. Shapley spoke, some of these astronomical mysteries have been solved, while other and many more new questions remain unsolved. Just before the lecture, the Poly interviewed Dr. Shapley. He had earlier a chance to see the Field House and the new dorms. He noted that just that afternoon he sent away his paper on the opacity of the Southern Milky Way. In answer to a question on radio astronomy, Dr. Shapley noted that Harvard will have a new 60-foot dish, becoming the largest radio telescope in America. However, he preferred the higher resolving powers of optical astronomy noting that stars are most intense in the visual region. Finally, Dr. Shapley discussed various theories on the creation of the Universe and summarized his main areas of astronomical research.

The third famous astronomer appeared at RPI's Sage Lecture Hall on Friday, December 8, 1950, at 8 p.m. Dr. George Gamow was a guest of the RAS. Charles Inman, an R.P.I. senior and President of the RAS introduced Dr. Gamow to the capacity audience. At the time, Dr. Gamow was one of the nation's foremost atomic scientists and distinguished astronomers. He spoke on the topic of the "Evolution of the Universe," and illustrated his talk with films and slides. Dr. Gamow explained, "There are several ways of obtaining an age for the Universe." He noted that in one of these methodologies, astronomers have estimated the upper limit for the age of the Universe by dynamical considerations, based on how long star clusters need to break up, on the order of 10 billion years. He noted that other methodologies included the radioactive decay of Uranium 235, and the distribution pattern of the elements throughout the Universe. He continued with an explanation of the expanding Universe, as it was understood at that time. Dr. Gamow was known for his enthusiastic and witty lectures. Dr. Gamow was the author of a number of books including The Birth and Death of the Sun, The Biography of the Earth, Mr. Tomkins in Wonderland, and One, Two, Three… Infinity, the later being a classic that nearly everyone with an interest in astronomy and physics read in the time before the Internet was created and made information searches easy. The Time Record newspaper article also spoke of Dr. Gamow's many accomplishments.

For more details and photographs of these events, the reader is encouraged to access the original Polytechnic issues on-line per the references below, as well as to visit the Troy Public Library to view the microfiche collection of the Times Record / Troy Record.

References

1. Rensselaer Polytechnic, Troy, N.Y., November 22, 1934, Vol. L, No. 11, Columbia Professor, Nobel Prize Winner, Gives Sigma Xi Talk, Talks on His Recent Work in the Study of Isotopes; Studied Under Prof Bray, pages 1 and 4.

2. Atomic Scientist Will Be Speaker of R.P.I. Society, Wednesday, December 6, 1950, The Times Record, Troy, N.Y., page 9.

3. The Rensselaer Polytechnic, Troy, N. Y., Wednesday, December 13, 1950, Vol. LXIX, No. 11, Gamow Expounds Creation Theory, pages 1 and 4.

4. The Troy Record (Troy, New York), Wednesday, January 13, 1954, Page 7. "Dr. Urey Calls McCarthy Probe Methods "Evil" (Sub-heading: "Dr. Urey Cites Own Theory on Moon"), by George J. Yamin

5. The Rensselaer Polytechnic, Wednesday, February 10, 1954, Urey Presented By Astrophysical Society; Talk Concerned With Moon's Surface. 200 Attend Meeting; Urey Tours School, Comments on Laws, by Stan Amberg, page 3.

6. RPI Group Hears Noted Astronomer, The Times Record, Troy, N.Y., Friday, March 25, 1955, page 5.

7. The Rensselaer Polytechnic, Wednesday, March 30, 1955, Harvard's Harlow Shapley Delivers Lecture on Galaxies, by Richard Davison, page 3.

8. The Rensselaer Polytechnic, Wednesday, March 30, 1955, Shapley Makes First Visit To RPI, by Hank Ruderman, page 6.