John Alexander Simpson was born 3 November 1916 in Portland, Oregon. His father, the youngest of five sons in Greenock, Scotland, came to Portland in 1910 and established a shoe and leather goods store there in the 1920's. His mother, Janet Christe Brand, also from Greenock, Scotland, was engaged to his father in Greenock and came to Portland to be married in 1914. A younger brother, William Brand, was born in 1919.

He married Elizabeth Alice Hilts in 1946. They had two children, Mary Ann born 1954 and John Alexander born 1958. He was divorced in 1977 and married Elizabeth Scott Johnson in 1980.

Simpson's early schooling, although delayed by illness, was in public elementary and high school, followed by Reed College, where he received the A.B. Degree in 1940 while majoring in physics. He undertook graduate work with a scholarship and teaching assistantship at New York University's Department of Physics at University Heights. He received a M.S. Degree in 1942 and Ph.D. Degree in 1943.

During Simpson's graduate years at New York University the United States entered W.W.II. After requesting an opportunity to help in the war effort, he received a visit in 1942 from Volney Wilson of the University of Chicago, an assistant of Arthur Holly Compton who was then director of the secret project (Metallurgical Laboratory) devoted to the first nuclear chain reaction and the production of plutonium for a nuclear bomb. Wilson encouraged Simpson to develop new radiation detectors which could be used to measure high intensity levels of radiation. In 1943, at the invitation of the Comptons, Simpson was given a room on the top floor of their home and was soon a scientific group leader for novel instrumentation and measuring methods required for the support of the ongoing work at Chicago, Hanford and Oak Ridge.

In 1945, Simpson requested permission to hold weekly seminars on the international control of atomic energy in Ryerson Hall. These seminars and discussions with senior physicists in the metallurgical Laboratory resulted in to the formation of the Atomic Scientists of Chicago in August 1945, with Simpson as Chairman. Soon thereafter similar organizations appeared at Oak Ridge and Los Alamos. Simpson participated in founding the Bulletin of Atomic Scientists in 1945 and was its first chairman. Activities in Washington, D.C. in the fall of 1945 through the Spring of 1946 by the Scientists' movement were important for the establishment of a civilian bill for the control of atomic energy.

In August 1945 Simpson accepted, along with about ten other physicists and chemists, an appointment in the newly-forming Institute for Nuclear Studies (now the Enrico Fermi Institute), at the University of Chicago, as well as a joint appointment as instructor in the Department of Physics and the College. Subsequently, his joint appointments included: Assistant Professor (1947), Associate Professor (1949) and Professor (1954). In 1968 he became the Edward L. Ryerson Distinguished Service Professor and in 1974 the Arthur H. Compton Distinguished Service Professor. From 1987 to the present time he is the Arthur H. Compton Distinguished Service Professor, Emeritus.

Among his administrative appointments at the University were: Chairman, Committee on Instruction and Biophysics (1951-52) and Director, The Enrico Fermi Institute (1973-78).

In 1962 he founded the Laboratory for Astrophysics and Space Research in the Enrico Fermi Institute.

Simpson's scientific career began as an undergraduate at Reed College where, for a Senior Thesis in 1939, he designed and constructed a two-stage electron microscope. The original aspects of that work were published by him in American Institute of Physics journals as his two first publications. After W.W.II he began investigations of the energy spectrum of the primary galactic cosmic ray protons by means of their production of a secondary nucleonic component cascade in the atmosphere. Using the fast neutron production as a tracer of the nucleon cascade he discovered the existence of the large latitude dependence of the cascade, whose production was shown to extend to very low primary particle energies. From these studies Simpson invented in 1948 the concept and instrumentation called the "Neutron Monitor Pile", based on the early nuclear chain reaction at Chicago, which enabled the investigations for the first time of the time-dependent intensity changes of the very low energy primary cosmic ray nucleon component. His studies of the time dependence of the nucleonic component over a wide range of incident primary energies led to the proof that the cosmic ray intensity variations were due to interplanetary electrodynamical processes of solar origin - called the solar modulation of the galactic cosmic rays. In 1950-51 he established a network of these neutron monitors extending from the geomagnetic equator to high latitudes. It was his neutron monitor network which recorded the flare of 23 February 1956 leading to his proof with colleagues P. Meyer and E.N. Parker that there existed a large-scale heliosphere of magnetic fields surrounding the solar system.

Simpson's neutron monitor design became the world standard for cosmic ray research sponsored by the 68 nations participating the International Geophysical Year.

Beginning with the Office of Naval Research's sponsorship in 1946, Simpson's early research was mainly supported by ONR and the U.S. Air Force which enabled him to undertake high altitude measurements with B-29 and RF-80 aircraft, and U.S. Navy icebreakers for investigations throughout the world extending from the magnetic equator to high latitudes in the pre-satellite era, 1947-57. Beginning alone and later with graduate students in the period 1946-53, Simpson brought P. Meyer to Chicago in 1953 and E.N. Parker in 1955 to expand the range of his researches, largely supported by federal funds. Following the launch of the first U.S.S.R. satellite in October 1957, unclassified U.S. rockets and satellites made available in 1958 enabled Simpson to undertake the development of an expanded laboratory and novel instrumentation to attack problems in cosmic ray, interplanetary phenomena and solar accelerated particles directly in the interplanetary medium and the trapped radiation belts of Earth. His first spacecraft experiment was on Pioneer-2, November 1958 (1).

It was in the period 1958-60 that Simpson laid out his three interrelated areas of research goals in space and programs to achieve them (2):

Simpson separated his publications into two lists - PART A is his list of scientific publications; PART B is his list of non-scientific writings. He listed as PART C the publications of the Ph.D. theses of students he supported. Finally, U.S. Patents issued to him are listed in PART D. (Parts A,B,C,D are in Appendix 1).

In general, the order in which the authors names appear in his publications is alphabetical unless a large number of individuals are given credit, for example, for the successful launch and initial report of an experiment on a space mission - e.g., Paper 245A, Appendix 1.

His experimental program in space would not have been possible without his development of a strong infra-structure which included a solid state sensor laboratory in 1959 and a dedicated technical staff which could transform original designs and models into flight-worthy instrumentation. Another component of the infra-structure was software development, computing and data analysis. All of these factors were brought together in the Laboratory for Astrophysics and Space Research's building, funded by NASA in 1962 and in full operation by 1964. Recognizing that his work represented modest-scale fundamental research in a university setting but that the space missions for carrying out these experiments were very large-scale efforts, Simpson evolved a style for the conduct of original research which interfaced small, fundamental science in the university with the "Big Science" aspects of major space missions. This included missions to the planets where many individuals and organizations were required by NASA to interact with the Principal Investigator. Simpson published his concept of the sociology for the conduct of original and successful space science programs in a university setting (Papers 12B, 13B, 14B).

In support of these concepts for the conduct of space science NASA provided "Technology for Science" grants to L.A.S.R. faculty from the mid-1960's to the early 1980's. These grants enabled Simpson and his colleagues to develop new concepts, including - for example, Simpson's invention of the polyvinylidene fluoride polymer sensors for detection of super heavy charged particles or mass measurements of dust particles in the coma of Comet Halley (1986). This technology support, plus the sequence of discrete space missions, provided a sustaining level of support for his group in L.A.S.R. The ability of his laboratory to respond rapidly to a new opportunity is illustrated by the invention of the dust detector in 1983, approved in 1983 by the U.S.S.R. and the U.S. to include instruments to Comet Halley, and their successful launches in the two VEGA spacecraft in 1984.

Federal support from ONR and the U.S.A.F. continued into the 1960's, along with the new space agency, NASA, until Congress passed the Mansfield Amendment requiring that all Department of Defense support to universities be related to direct military objectives. At this point Simpson refused to compromise the university's research program and realigned his research support through NASA and the N.S.F.

The flight program and space missions carrying Simpson's instruments and experiments are illustrated in Appendix 2. There were two major periods where NASA was unable to provide access to space for Simpson's experiments. The first period was 1960-62 (including the failure of the Ranger Missions). In this interval Simpson obtained three unclassified space flights by riding "piggyback" on military missions - i.e., the Discoverer series. The second interval, approximately 1976-1989, was caused mainly by NASA's focus on its ill-fated decision to discontinue expendable launch vehicles and to concentrate on shuttle launches. The Challenger accident in 1986 accentuated this problem. For this period Simpson again turned to ONR for non-funded sponsorship of NASA-financed instruments to be carried unclassified on U.S> Air Force missions. In Appendix 3 there is a block diagram illustrating the successive stages of efforts which led to the launch of Phoenix-1 (1982), Phoenix-2 (CRRES satellite, 1990) and EHIC (TBD 1991), along with the Ulysses spacecraft which was postponed from 1983 to its launch in 1990. It was in this period (1975-1990) that the out-of-ecliptic mission was initiated - realized first as the "ESA/NASA International Solar Polar Mission" and later as the ESA spacecraft designated Ulysses to "fly" over the poles of the Sun. This was a mission which Simpson had been urging NASA to undertake since the early 1960's and one where he and his staff had developed the required instrumentation in the 1960's and 1970's. (See Appendix 3).

Although this period was a difficult one for gaining access to space for new missions, it continued to be a productive and creative period for research. Pioneer-10, Pioneer-11, IMP 7, IMP 8 and Mariner-10 (along with neutron monitors in Peru and Colorado) constituted a heliosphere "laboratory" for astrophysical investigations covering the triad of objectives noted above.

Since the deep space missions were mainly justified by planetary encounters, Simpson designed his experiments to take advantage of both their interplanetary travel phase and, by using different sensors or operational modes, the mission planetary encounters to study planetary magnetospheric particle acceleration. Continuous observations and investigations over four successive periods of 11 year minima of solar activity and more than one and one-half solar magnetic cycle have provided a unique set of data for investigating both high energy astrophysical phenomena surrounding a typical rotating magnetic star and for galactic cosmic ray studies.

A list of the principal discoveries and developments derived from these investigations by Simpson, his students and staff is in Appendix 4.

The writings listed in PART B (Appendix 1) reflect Simpson's personal view that scientists have an obligation to use their knowledge and approach to the solution of problems to influence national and international efforts for controlling the use of nuclear weapons and for promoting cooperation among nations. This view accounts for his extracurricular activities on behalf of the peaceful uses of nuclear energy, as well as his participation in the 68 nation International Geophysical Year as one of its twelve science organizers during the period of the so-called Cold War. It also was a factor in the pre-glasnost cooperative space effort to Comet Halley on two Soviet spacecraft. His support for the participation of universities in the U.S. civil space program led to his organizing the Space Science Working Group in Washington, DC (1982).