The International Geophysical Year (IGY), 1957-58

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The International Geophysical Year (IGY), 1957-58

Overview

The International Geophysical Year (IGY) was prompted by a lack of concise data about Earth and its land, oceans, and atmosphere. Post-World War II technology had become available to launch a worldwide research effort to solve questions concerning the physical processes, patterns, and cycles of the forces of nature—the geophysics of the earth. During the IGY, global cooperative research expanded knowledge of Earth itself, the lower and upper atmosphere, the oceans, the polar regions, and near space, where the first satellites orbited successfully.

Background

Through the nineteenth century marine and polar exploration had highlighted the earth as a natural laboratory for research and brought new emphasis to the development of modern Earth sciences—geology, meteorology, and oceanography. The mystery of the polar regions stimulated the first cooperative, multinational scientific effort, the International Polar Year (1882-1883), but it was hardly international and consisted of failed expeditions. The world's scientific community tried again during the Depression but many countries could not honor their commitments. The end of World War II, however, brought a new technological age.

In 1950 a group of geophysicists met at the home of American physicist James Van Allen (1914- ). Present were the world-renowned English geophysicist Sydney Chapman (1888-1979) and two other Americans, physicist and engineer Lloyd Berkner (1905-1967) and geophysicist S. Fred Singer (1924- ). They discussed acquiring comprehensive upper-atmospheric data from the application of such post-war technology as radar, radiation sensors, sonar, rockets, high-performance aircraft, and the computer. Berkner suggested another polar year was needed; instead, they agreed the whole Earth should be studied. This meeting was the seed for the IGY. The idea was worked on for the next two years by a four-nation committee (the United States, Britain, France, and the Soviet Union) headed by Chapman and guided by the International Council of Scientific Unions.

Chapman came up with an appropriate new name, the International Geophysical Year. All IGY projects were to focus on "specific planetary problems of the earth" with emphasis on the Arctic and Antarctica, the equatorial regions, pole-to-pole profiles of atmospheric circulation, electrical layers of the ionosphere, the ocean depths, geodesy, seismic research, and geomagnetism. The ambitious showcase projects were to orbit the first artificial satellites and to explore Antarctica thoroughly. The massive organizational logistics would take some years. The period 1957 to 1958 (a year of maximum solar activity and several eclipses) was far enough ahead to make the preparations feasible. The ambitious research agenda actually required that the IGY be lengthened to 18 months (July 1, 1957, to December 31, 1958).

The near-space research was much anticipated. It was the beginning of the exploration of the "last frontier." Both the United States and the Soviet Union had taken advantage of German rocketry technology; few, however, knew that the Soviets were advanced in the design of large rocket engines. With the capture of the German V-2 rocket arsenal and under the leadership of Wernher von Braun (1912-1977), from 1946 to 1951 U.S. scientists such as Van Allen launched V-2s with payloads, bolstering American military rocket designs. By the late 1940s Singer suggested that it was possible to launch "artificial moons"—satellites—into orbit around Earth.

The satellite addition to the IGY agenda called for both American and Soviet satellites to be launched simultaneously to orbit the earth, recording and transmitting data on the geomagnetic field, the layers of the ionosphere, solar radiation, and cosmic rays. (The U.S. Navy and Air Force arrogantly competed with the Army for the launching of America's first satellite, believing the Soviets were far behind the West.) Satellite data would augment atmospheric data obtained using instrument packages on high-altitude balloons as well as small sounding rockets and earthbound sensors. Van Allen had designed a "rockoon," a balloon-born rocket, for the IGY to study cosmic rays, which were known to be the most energetic radiation in the universe and were an IGY emphasis.

Comprehensive worldwide ground observations of many geophysical phenomena were also an IGY goal. A study of the aurora (located about 70 miles [113 km] up) involving dense ground observations of the upper latitudes was organized. The airglow (low-energy ionization of oxygen) was to be studied using ground and rocket-mounted photometers. The obtainment of the first exact data on stratospheric ozone (tri-atomic oxygen) was slated. For the lower atmosphere, the troposphere, there would be extensive airborne and ground analyses of air masses (particularly the origins of Antarctic weather systems), the structure of the high-velocity jet stream, and wind patterns in the Pacific Ocean and southern hemisphere. And lower still, on Earth and its oceans, an extensive data base would be created: geologists and seismologists would gather geothermal, gravitational, and geodetic data to delineate Earth's structure (with special emphasis on earthquake data); and oceanographers would obtain data on deep-ocean basins, protein sources, ocean chemistry, currents and countercurrents, the effects of climate change, and sea-level variation.

The greatest earthbound challenge to the IGY was the study of the polar regions. Since the Arctic was a more familiar region, a greater emphasis was placed on Antarctica. While the Arctic is basically an ice cap over the ocean, Antarctica is a landmass covered with snow and ice. Was Antarctica an extension of South America, two islands, or a continent? The IGY was the time to find out. For the Arctic expedition, the United States and Soviet Union each committed to camping on a large Arctic ice floe, literally floating through the Arctic Ocean to collect all manner of data. Long-term planning for Antarctica called for at least 20 research stations, both on the coast and in the interior, with 179 people scheduled for research work. The actual numbers would involve 48 stations and 912 people, requiring huge airlift operations to build the stations and stockpile supplies as well as the establishment of routes in the interior. The military led the U.S. effort, called Operation Deep Freeze, beginning in 1954.

Impact

By the start of IGY research, 67 countries were involved with over 60,000 scientists and technicians. With data compiled at three data collection centers, the momentous project became a reality. A more sobering reality, however, was to become clear.

The first artificial satellites were launched—but with ironic results. On October 4, 1957, the West woke up to the Soviet's Sputnik I in orbit; the Soviets had not waited for a simultaneous launch. Though the Soviets tried to downplay the situation, the United States was angry and suspicious of a Communist agenda. The Soviet Union then launched its even larger Sputnik II on November 3 with a dog aboard. The U.S. political establishment, galled by its complacency over the technological superiority of the United States, drove American IGY satellite officials to launch more satellites than the Soviets. The U.S. Navy had won launching rights for its small Vanguard satellite atop a new rocket design, but technical problems ended in two humiliating failed launches. Von Braun stepped in with the simpler Explorer I satellite, which was essentially a small rocket fitted with instruments. Riding atop the big Army Redstone (to become the Jupiter C) on January 31, 1958, it became the first U.S. satellite in orbit. Vanguard was finally sent into orbit on March 17, 1958, followed about a week later by Explorer III (along with Explorer IV and V in the summer). On May 15 Russia put its last IGY satellite, Sputnik III, into orbit.

The irony of these events was that, in fact, U.S. technology was superior to the Soviet's, even though they had won the race into space. The Soviets actually had to use large rockets to get large satellites into orbit because their electronic instrumentation was antiquated, whereas the United States was far ahead in electronic miniaturization of instruments, affording the use of smaller satellites. Explorer I telemetered the data Van Allen used to identify the belts of charged particles (wrongly called radiation) trapped by Earth's magnetic field and named for him. Tiny but sophisticated, Vanguard amassed far more data than all the Russian satellites put together. Yet, the period was the Cold War and the Space Race was on. (The United States announced it would put a man on the moon by the end of the 1960s—a race it did win.) The dawn of the artificial satellite became controversial; were there national rights to orbital air space and what of non-satellite nations' rights? The satellite as both "spy in the sky" and weapon joined nuclear war as another threat.

Though it was never on the IGY agenda, a secret project took place. This project was "Argus," a U.S. military experiment in which three rocket-propelled nuclear electron shells were detonated in near space (above fallout levels) by the Navy in the South Atlantic in the summer of 1958. The resulting auroral displays and communication blackouts were recorded by unsuspecting IGY stations as astonishing anomalies—but many scientists had their suspicions. At a time when nuclear testing was under heated negotiations, Argus was a potential embarrassment, which explains why the U.S. government did not admit to the project until 1959. Nevertheless, nuclear testing was carried out during the IGY—137 detonations—with the purpose of studying fallout using different altitudes and wind conditions. The results showed that fallout fell more quickly than had naively been supposed, helping the later ban on atmospheric nuclear testing.

The call for a dense network of seismic stations revitalized defunct stations, and instruments that had been reserved for monitoring nuclear testing were put to a more humane purpose. At least 100 additional stations were activated, including in China, which, though withdrawing from the IGY, invited the IGY seismic coordinator, the Canadian geophysicist J. Tuzo Wilson (1908-1993), to survey their installations. Mother Nature cooperated admirably with IGY research. A huge solar flare in November 1958 provided the greatest number of magnetic storms ever recorded. Along with many volcanic eruptions during the IGY, in December 1957 one of the largest earthquakes on record occurred in central Asia, the Gobi-Altai Quake, which flattened a mountain range and drained a lake. Coupled with a great store of data on ocean-floor mountains and faults, the geological and seismic data helped formulate the new plate tectonic theory of Earth.

Some 20 nations operating on 86 vessels combed the oceans, mapping deep-water circulation. Sounding for the deepest ocean floors was tedious—the Pacific's was the deepest with trenches tens of thousands of feet deep. The Marianas Trench was the deepest at over 36,000 feet (11,000 m). The idea of "ancient water" (water so deep it does not circulate) was found to be false. America's most active oceanographers—Columbus Iselin (1904-1971), Maurice Ewing (1906-1974), and Roger Revelle (1909-1991)—led important IGY projects in the study of (respectively): salinity, temperature, and currents; ocean basins and sediments; and the warming climate's relation to oceanic carbon dioxide balance. English oceanographer John Swallow (1923- ) used his neutral buoyancy float in the Atlantic Gulf Stream, finding a countercurrent beneath it.

Knowledge of the North and South Poles was advanced by the IGY. Innovations in resupplying research stations were made when two U.S. submarines surfaced through the ice at the North Pole to deliver supplies for the ice floe research stations. The measurement of ice areas in the Arctic, the continental mountains, and the Antarctic indicated that the world's ice was in a melting stage and thus that the climate was warming. The research conducted in Antarctica had been spectacular, including all manner of geophysical observations, such as climatic information reaching back thousands of years taken from drilled ice cores. The United States and Soviet Union volunteered for the most isolated observation stations, the South Pole and the Pole of Inaccessibility (the exact center of Antarctica), respectively. Traverses, overland scientific trips, involved the United States, Soviet Union, Britain and Commonwealth nations such as Australia and New Zealand, and France. Some of these traverses were not completed until 1959. The longest, most publicized traverse was the British Trans-Antarctic Commonwealth Traverse led by geologist Sir Vivian Fuchs (1908- ), which crossed the whole of the landmass in 99 days, proving via detailed seismic and geodetic surveying that Antarctica was one continent, a great basin with central highlands. Antarctica was the real test of IGY cooperation. Historically, there had been many claims and disputes over the area. Worldwide cooperation, however, resulted in a seven-article scientific treaty, making Antarctica a natural laboratory to be shared by all nations—which it still is.

Another significant result of the IGY was that data on the influence of the Sun's radiation on the planets of the solar system fostered a new perspective on Earth's integration with the solar system and the cosmos beyond. The IGY data storehouse, moreover, was a springboard to the delineation of further specialized geophysical disciplines, such as geochemistry, tectonophysics, space physics, and planetology. As a humble epitaph to the IGY, Chapman said in a 1958 lecture, "The time will come when the International Geophysical Year will be viewed as an important but primitive contribution to the exploration of the cosmos." Instead, the IGY should be remembered as a great deal more.

WILLIAM J. MCPEAK

Further Reading

Antarctica in the International Geophysical Year. Geophysical Monographs No. 1, American Geophysical Union, 1956.

Bates, D. R. The Earth and Its Atmosphere. New York: Basic Books, 1957.

Berkner, Lloyd. Rockets and Satellites. New York: Mc-Graw-Hill, 1958.

Berkner, Lloyd, and Hugh Odishaw, eds. Science in Space. New York: McGraw-Hill, 1961.

Chapman, Sydney. IGY: Year of Discovery. Ann Arbor: University of Michigan Press, 1959.

Odishaw, Hugh, ed. Earth in Space. New York: McGraw-Hill, 1962.

Siple, Paul. 90 Degrees South. New York: Putnam & Sons, 1959.

Sullivan, Walter. Assault on the Unknown. New York: Mc-Graw-Hill, 1961.

Wilson, J. Tuzo. IGY, The Year of the New Moons. New York: Alfred A. Knopf, 1961.


SATELLITES AND ANXIETY DURING THE IGY

Though reactions were mixed following Russia's unannounced launch of Sputnik I in October 1957, curiosity about the first "artificial moon" or satellite was tremendous. Cold War fears before the International Geophysical Year (IGY) had already put the anticipated launch of satellites into a negative perspective. Some armchair political analysts predicted world domination would be played out in the near space of Earth by those with the most sophisticated satellites.

But people worldwide stepped outside an hour or so after sunset—or before sunrise—to catch a glimpse of Sputnik I, the polished metal 185-pound (84 kg) sphere that streaked overhead every 95 minutes, lit like a star from the sun's reflection. American gazers watched in awe, but wondered if it carried spy cameras or maybe a bomb on board. The U.S. satellite effort was behind, and the anxiety of failure was heightened by the lack of technical cooperation from the Russians in trying to track Sputnik.

The U.S. visual tracking program for Vanguard was called Moonwatch (the Russians also had a program, but not as organized), under the supervision of the Smithsonian Astrophysical Observatory with volunteers at home and around the globe. Official observers were given a special short, rich-field telescope and tasked with scanning a set area overhead (along the meridian). Unofficial watchers gathered in large groups, using their own binoculars and telescopes. Moonwatch tracked Sputnik I and then the larger Sputnik II, when it was launched in early November 1957. They turned to tracking the successful U.S. Explorer I and Vanguard I in early 1958. These satellites were much smaller, so more challenging to observe. The original IGY satellites fell back to earth over time-spans measured in months—except tiny Vanguard I, which still orbits Earth.


NEARBY TERMS

The International Geophysical Year (IGY), 1957-58