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James Alfred Van Allen (born September 7 1914 ) is considered America's foremost space scientist. A majority of his career in research and teaching has been at the University Of Iowa . The Van Allen Radiation Belt s were named after him, following the 1958 Satellite missions ( Explorer I and Explorer III ) in which Van Allen had argued that a Geiger Counter should be used to detect charged Particle s. “Certainly one of the most enthralling things about human life is the recognition that we live in what, for practical purposes, is a universe without bounds.” James Van Allen. HONORS
TIMELINE (1914-PRESENT)
James Van Allen was born in Mount Pleasant, Iowa .
James Van Allen graduated as valedictorian of his Mount Pleasant Public High School class.
Van Allen received his Bachelor of Science degree, summa cum laude, from Iowa Wesleyan College in Mount Pleasant. During his undergraduate years, he studied with Professor Thomas Poulter, a first-class physicist. He tracked meteors, conducted a magnetic survey of Mount Pleasant, and measured cosmic rays at ground level.
Van Allen earned his master’s degree in solid state physics from the University Of Iowa .
Van Allen received his Ph.D. in nuclear physics from the University Of Iowa . His doctoral research was on measuring the cross-section of the deuteron-deuteron reaction.
As a staff physicist for the Department of Terrestrial Magnetism of the Carnegie Institution in Washington, D.C., Van Allen worked on developing photoelectric and radio proximity fuses for bombs, rockets, and gun-fired projectiles. It was here that Dr. Van Allen acquired his interest in cosmic rays.
Van Allen joined the Applied Physics Laboratory (APL) of Johns Hopkins University to continue his work on proximity fuses. Later in 1942, he entered the Navy, serving in the South Pacific Fleet as an assistant gunnery officer.
Discharged from the Navy, Van Allen returned to civilian research at APL. He organized and directed a team at John Hopkins University to conduct high-altitude experiments using V-2 rockets, captured from the Germans at the end of World War II , to survey sounding rocket requirements for upper atmosphere research. The V-2 was found to be too heavy and complex for this task. Van Allen decided that what was needed was a small rocket, derived from the Aerojet WAC Corporal and the Bumblebee missile developed under a US Navy program. He drew specifications for this combination of an Aerojet booster and a Bumblebee second stage for this cheaper rocket, dubbed the Aerobee and headed the committee that convinced the U.S. government to produce it. Aerobees were launched for 53 m tall launch towers to provide the necessary stability until enough speed had been gained for the fins to be effective in controlling the rocket. Launch towers were built at White Sands Missile Range , Fort Churchill, Wallops Island, and aboard the research ship USN Norton Sound. The Aerobee could take a 68 kg payload to an altitude of 130 km.
The concept of launching of small high-performance rockets suspended from a balloon above most of the atmosphere (later called "Rockoons"), developed by Cmdr. Lee Lewis, Cmdr. G. Halvorson, S. F. Singer, and J. A. Van Allen during Aerobee firing cruise of U.S.S. Norton Sound.
Van Allen left APL to accept a John Simon Guggenheim Memorial Foundation research fellowship at the Brookhaven National Laboratory . TIME magazine reported in 1959, “In 1950 an event occurred that began small but was to affect the future of Van Allen and all his countrymen. In March, British Physicist Sydney Chapman (astronomer) dropped in on Van Allen {Link without Title} remarked that he would like to meet other scientists in the Washington area. Van Allen got on the phone, soon gathered eight or ten top scientists ( Lloyd Berkner , S. Fred Singer , and Harry Vestinein ) the living room of his small brick house. ‘It was what you might call a pedigreed bull session,’ he says. “The talk turned to geophysics and the two ‘ International Polar Years ’ that had enlisted the world’s leading nations to study the Arctic and Antarctic regions in 1882 and 1932. Someone suggested that with the development of new tools such as rockets, radar and computers, the time was ripe for a worldwide geophysical year. The other men were enthusiastic, and their enthusiasm spread around the world from Washington DC. From this meeting Lloyd Berkner and other participants proposed to the International Council of Scientific Unions that an IGY be planned for 1957-58 during the maximum solar activity). “The International Geophysical Year (1957-58) stimulated the U.S. Government to promise earth satellites as geophysical tools. The Soviet government countered by rushing its Sputniks into orbit. The race into space or Space Race may be said to have started in Van Allen’s living room that evening in 1950.” “...Outer space, once a region of spirited international competition, is also a region of international cooperation. I realized this as early as 1959, when I attended an international conference on cosmic radiation in Moscow. At this conference, there were many differing views and differing methods of attack, but the problems were common ones to all of us and a unity of basic purpose was everywhere evident. Many of the papers presented there depended in an essential way upon others which had appeared originally in as many as three or four different languages. Surely science is one of the universal human activities.”
James Van Allen became head of the physics department at the University Of Iowa . Before long, he was enlisting students in his efforts to discover the secrets of the wild blue yonder and inventing ways to carry instruments higher into the atmosphere than ever before. Van Allen was the first to devise a balloon-rocket combination that lifted rockets on balloons high above most of Earth’s atmosphere before firing them even higher. The rockets were ignited after the balloons reached an altitude of 16 kilometers.
As TIME reported in 1959, “Van Allen’s ‘ Rockoon s’ could not be fired in Iowa for fear that the spent rockets would spike an Iowan or his house.” So Van Allen convinced the U.S. Coast Guard to let him fire his rockoons from the icebreaker Eastwind that was bound for Greenland. “The first balloon rose properly to 70,000 ft., but the rocket hanging under it did not fire. The second Rockoon behaved in the same maddening way. On the theory that extreme cold at high altitude might have stopped the clockwork supposed to ignite the rockets, Van Allen heated cans of orange juice, snuggled them into the third Rockoon’s gondola, and wrapped the whole business in insulation. The rocket fired.”
Rockoons fired off Newfoundland detect the first hint of radiation belts surrounding Earth. The low-cost Rockoon technique was later used by the Office Of Naval Research and The University Of Iowa research groups in 1953-55 and 1957, from ships in sea between Boston and Thule, Greenland.
Symposium on "The Scientific Uses of Earth Satellites" held at the University of Michigan under sponsorship of the Upper Atmosphere Rocket Research Panel, James A. Van Allen of The University of Iowa, Chairman.
The Upper Atmosphere Rocket Research Panel was renamed the Rocket and Satellite Research Panel. Its chairman was James A. Van Allen of The University Of Iowa .
The International Geophysical Year begins. IGY is carried out by the International Council of Scientific Unions. This 18 month time period was selected due to period of maximum solar activity (e.g. Sun Spots ). Lloyd Berkner , one of the scientists at the April 5, 1950 Silver Springs, Maryland meeting (Van Allen's home), serves as president of the ICSU from 1957 to 1959.
Thirty-six Rockoons (balloon-launched rockets) were launched from Navy icebreaker, U.S.S. Glacier, in Atlantic, Pacific, and Antarctic areas ranging from 75 N. to 72 S. latitude, as part of the U.S. International Geophysical Year scientific program headed by James A. Van Allen and Lawrence J. Cahill of The University Of Iowa . These were the first known upper atmosphere rocket soundings in the Antartctic area. Launched from IGY Rockoon Launch Site 2, Atlantic Ocean - Latitude: 0.83 N, Longitude:0.99 W.
The Soviet Union (USSR) successfully launches Sputnik 1 , the world's first artificial satellite, as their participation in the 1957-58 IGY. The first American satellite, Explorer 1 , was launched into Earth's orbit on a Jupiter C missile from Cape Canaveral, Florida. Aboard Explorer 1 were a micrometeorite detector and a cosmic ray experiment designed by Dr. Van Allen and his graduate students. Data from Explorer 1 and Explorer 3 (launched March 26 1958 ) were used by the Iowa group to make the first space-age scientific discovery: the existence of a doughnut-shaped region of charged particle radiation trapped by Earth’s magnetic field.
United States Congress passed the National Aeronautics and Space Act (commonly called the "Space Act"), which created the National Aeronautics and Space Administration NASA as of October 1, 1958 from the National Advisory Committee for Aeronautics (NACA) and other government agencies.
magazine.]] Pioneer 3 , the third U.S. International Geophysical Year intended lunar probe under the direction of NASA with the Army acting as executive agent, was launched from the Atlantic Missile Range by a Juno II rocket. The primary objective of the flight, to place the 12.95 pound scientific payload in the vicinity of the moon, failed. Pioneer III did reach an altitude of 63,000 miles, providing Van Allen additional data that led to discovery of a second radiation belt. Trapped radiation starts at an altitude of several hundred miles from Earth and extends for several thousand miles into space. The Van Allen Radiation Belt s are named for Dr. James Van Allen, their discoverer.
The International Geophysical Year ends.
TIME magazine writers credited James Van Allen as the man most responsible for giving the U.S. “a big lead in scientific achievement.” They called Van Allen “a key figure in the cold war’s competition for prestige. ...Today he can tip back his head and look at the sky. Beyond its outermost blue are the world-encompassing belts of fierce radiation that bear his name. No human name has ever been given to a more majestic feature of the planet Earth.” magazine.]]
Since 1960, James Van Allen, his colleagues, associates and students at The University Of Iowa have flown scientific instruments on sounding rockets, Earth satellites ( Hawkeye 1 ), and interplanetary spacecraft -- including the first missions ( Pioneer Program , Mariner Program , Voyager Program , Galileo Spacecraft ) to the planets Venus, Mars, Jupiter, Saturn, Uranus, and Neptune. Their discoveries have contributed important segments to the world's knowledge of energetic particles, plasmas and radio waves throughout the solar system.
On Saturday, October 9, 2004, The University Of Iowa and the UI Alumni Association hosted a celebration to honor Professor James Van Allen and his many accomplishments, and in recognition of his 90th birthday. Activities included an invited lecture series, a public lecture followed by a cake & punch reception, and an evening banquet.
Dr. Van Allen retired from The University of Iowa in 1985, but continues to live in Iowa City and serves as the Carver Professor of Physics, Emeritus. IN SEARCH OF THE HELIOPAUSE ''Main article: Heliopause '' It is a scientific saga of pure discovery, of sleepless nights spent poring over reams of data no one had ever seen before, of frantic effort, desperate gambles, inspired ingenuity, and plain hard work. Finally, it is a tale of surprises, of continually realizing the unexpected. A few days before the 1972 launch of Pioneer 10 , a United Press International report noted that ''"by the time the probe approaches the orbit of Uranus in 1979, {Link without Title} will be out of communications range of earth and will continue as a silent derelict of space."'' Certainly that was the expectation of nearly all who had built and worked on Pioneer, and it would mean that the spacecraft had more than accomplished its mission. It didn't turn out that way. Over 20 years later, in the summer of 1999, Pioneer 10 was far beyond Uranus -- far beyond Pluto, in fact. Yet it was not quite a "silent derelict of space." The craft was low on power, with most of its instruments turned off, but as project manager Larry Lasher confirmed, ''"The signals are weak, but they're still coming."'' Arthur C. Clarke once said that ''"the only way to define the limits of the possible is to push beyond them into the impossible."'' Pioneer 10 and its brethren prove Clarke's words. Or as the New York Times observed after Pioneer 10 reached Jupiter, ''"Despite this planet's troubles, there is very little beyond the reach of man."'' This is how the search for the heliopause started. NASA might have relegated the Pioneer 10 and Pioneer 11 spacecraft to the historical and administrative dust pile in 1980, but the spacecraft themselves appeared to have other ideas, stubbornly refusing to accept official proclamations of their demise even as the humans who built and launched them retired or moved on to other projects. For some of the Pioneer principal investigators, the missions were essentially over after the planetary encounters in 1980. For the particles and fields investigators, though, the mission continued. Van Allen's Geiger Tube Telescope , Simpson's charged particle experiment, and Frank McDonald's cosmic ray telescope were free of the intense and overpowering radiation flux of the planets, but they still had a lot to do. Now well past the interference of the planetary magnetospheres, they were searching for the edge of the solar system itself, the physical boundary that separates the Sun's realm of influence from the rest of the galaxy. The casual observer might consider the obvious outer marker of the solar system to be the orbit of Pluto, the farthest planet from the Sun. But that's only one possible definition and one that discounts the most important member of the solar system, the Sun itself. For astronomers, defining the true edge of the solar system means finding the region where the sun no longer holds sway, where the solar wind dwindles and vanishes, superseded by the interstellar medium. This is called the Heliopause , and with the conclusion of the planetary encounters of Pioneers 10 and 11, the heliopause became the new, if rather more ephemeral, destination of the two spacecraft. How far out did the heliopause go? ''"In the early part of the mission the solar wind limit was thought to be just beyond the orbit of Jupiter,"'' Van Allen said. Pioneer 10 quickly disproved that notion. The extent and intensity of the solar wind could be gauged by the way in which it affected, or modulated, the flux of cosmic rays coming from outside the solar system. Basically, the more galactic cosmic rays that were detected, the weaker the solar wind, and vice versa. The ratio between the two factors is called the galactic cosmic ray gradient, and it was expected to increase sharply after Pioneer 10 left Jupiter. It didn't, much to the surprise of Van Allen and the other particles and fields PIs. The influence of the Sun was felt much farther than previously expected. A switch failure in the Pioneer 11 radio system on October 1, 1990 disabled the generation of coherent Doppler signals used for tracking, so no additional data was received from that craft for investigation into the Pioneer Anomaly . The Pioneer 11 instruments were shut down on September 9, 1995, when there was no longer enough power. The program officially ended on March 31, 1997. Pioneer 11 continues on its way toward the constellation Aquila (the Eagle). It may pass by Lambda Aquila, the magnitude 3.4 star that marks the Eagle’s tail, in about 4 million years. Routine communication with Pioneer 10 ended on March 31, 1997 (end of program), controllers occasionally checked in with it. Pioneer's last signal was received on Janaury 23, 2003 at a distance of 86.34 AU. The round-trip radio signal took 23 hours and 55 minutes. In early March 2006, for the very last time the Earth was in a favorable position to receive Pioneer 10's radio signal. Pioneer Anomaly Team member Slava Turyshev reported on March 6, 2006 that no signal was heard from this final attempt to make contact with Pioneer 10. Pioneer 10 is now heading in the general direction of Aldebaran, the red giant star in the constellation of Taurus. At its current speed (12.18 km/sec), it would take about 2 million years to get to Aldebaran. The Search for the Heliopause and its structure - continues. PIONEER ANOMALY The persistence of the original principal investigators (Van Allen's Geiger Tube Telescope , Simpson's charged particle experiment, and Frank McDonald's cosmic ray telescope) to continue the Pioneer program (Pioneer 10 and 11) beyond 1980 has provided invaluable data for the study of the ''Pioneer Anomaly''. ''Main article: Pioneer Anomaly '' Analysis of the radio tracking data from the Pioneer 10 and 11 spacecraft at distances between 20–70 AU from the Sun has consistently indicated the presence of an anomalous, small Doppler frequency drift. The drift can be interpreted as being due to a constant acceleration of (8.74 ± 1.33) × 10−10 m/s2 directed towards the Sun. Although it is suspected that there is a systematic origin to the effect, none has been found. As a result, the nature of this Anomaly has become of growing interest. EXTERNAL LINKS
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