Astronomy Bio...James A. Van Allen
Jay Bitterman
James A. Van Allen was born on September 7, 1914 in Mount Pleasant Iowa to Alfred Morris and Alma Olney Van Allen. He was the second oldest of their four boys. His boyhood favorite magazines were Popular Mechanics and Popular Science from which he followed directions to make a crystal radio, electric motors and a tesla coil that produced a foot long spark. In his senior year (1930) he took his first course in physics. Van Allen graduated as class valedictorian from Mount Pleasant High School in June 1931. He then entered Iowa Wesleyan College in Mount Pleasant. The only astronomy course that he ever took used Moulton's 1933 "Astronomy". In 1935 he graduated Iowa Wesleyan College with a BA and went on to study Physics at the University of Iowa under the guidance of Edward Tyndall. In June 1936 he received an MS. for his experimental thesis, "A Sensitive Apparatus for Determining Young's Modulus at Small Tensional Strains". In June of 1939 he earned his PhD from the University of Iowa for his research paper "Absolute Cross-Section for the Nuclear Disintegration H2 + H2 -> H1 + H3 and Its Dependence on Bombarding Energy".
From 1939 to 1942 Van Allen accepted employment with the Department of Terrestrial Magnetism (DTM) as a Research Fellow at the Carnegie Institution of Washington, where he studied photodisintegration. In April of 1942 Van Allen transferred to the Applied Physics Laboratory at the Johns Hopkins University to develop a rugged vacuum tube. He also assisted in the development of proximity fuses for war weapons, particularly for U.S. Navy anti-aircraft projectiles. In the fall of 1942, he received a Naval officer commission and was sent to the Pacific to field test and conclude operational requirements for the proximity fuses.
He continued to serve in the U.S. Navy as an Ordnance and Gunnery Officer from 1942 to 1946. In March of 1946 he transferred to the inactive reserve as a Lieutenant Commander. Also, in 1946 Van Allen supervised the development of the Aerobee, a high altitude rocket for scientific research. The research at Applied Physics Department of Johns Hopkins University (1946 to 1951) involved the study of cosmic rays, solar ultraviolet, high altitude photography, atmospheric ozone, and ionospheric current systems.
In 1949 he designed the rocket balloon (rockoon) to lift a small rocket into the stratosphere and then fire it in order to reduce it's drag. This technique allowed him to determine the intense zones of high level radiation, caused by trapped charge particles around the Earth. . During the years from 1949 to 1957, he organized a total of five scientific expeditions to study cosmic radiation.
In 1951 Van Allen was appointed a Professor of Physics at the University of Iowa and in 1959 this post was extended to include him as Professor of both Astronomy and Physics.
In 1955 Van Allen was given the responsibility for the instrumentation of Explorer I that was launched on January 31, 1958. It carried a Geiger counter to measure levels of cosmic radiation. To his amazement the counter registered zero at a height of 800 km. He thought that there was an instrument failure but he got the same results for the device that was on Explorer III. He concluded that the counters must have been swamped with enormously high levels of radiation, since on returning to lower altitudes they resumed normal operation. He decided to shield the radiation counter that was to be carried on Explored IV with lead to reduce the penetration of radiation. Now the counter functioned normally. It was apparent that certain zones of the space around the Earth had much higher radiation levels that were previously suspected. Van Allen found that there were two zones of radiation in the shape of torroidal belts at the earth's equator. These high radiation zones were named the Van Allen belts. The flight paths of astronauts was carefully planed to avoid them because they posed a potential hazard
He was active in the "Project Matterhorn" that was involved in the in studding thermonuclear reactions from 1953 to 1954. From 1957 to 1958 he was also intimately involved in the organization of the International Geophysical Year. Since 1972 Van Allen has been Carver Professor of Physics at the University of Iowa.
From the time of 1951 to 1985 Van Allen was the head of the University of Iowa's Department of Physics which, in 1969, became the Department of Physics and Astronomy. Among all of the many courses that he taught, for 17 years, General Astronomy was his favorite.
