Stephen Wilson Kahler was born Friday, 28 July 1939, at Huron Road Hospital in East Cleveland, OH, the first child of Karl Myron Kahler and Mary Jenkins Kahler. He was named after his maternal great- great grandfather, Dr. Stephen R. Wilson, a practicing physician and farmer in Mercer County, OH, where he was also county coroner for four years. Karl and Mary Kahler had two younger sons, Thomas Noel Kahler, born 1942, and Victor Judson Kahler, born 1954 (deceased). Stephen's early years were spent in Chagrin Falls, OH, until the family moved to Westerville, OH, in 1947, when Karl joined the Ohio Council of Retail Merchants in Columbus, and Stephen entered third grade in the Vine Street school of Westerville Public Schools. The family lived at 44 West Home St. until they moved to a newly built home outside Westerville at 6912 Cleveland Ave. about 1953. Stephen graduated from Westerville High School in 1957 in a class of 105 students.
During his high school years Stephen developed four interests that lasted his lifetime. The first was biking, initiated by a birthday present from his parents of a Columbia bicycle, now termed a fat-tire bike. While using the bike for rides around Westerville, it served as transportation for newspaper routes during the summers of 1951, 1952 (Columbus Dispatch), and 1953 (Ohio State Journal). The move to Cleveland Avenue made biking more important, now for going to and from Westerville. However, the bike was abandoned while attending OSU and after leaving for California in 1961. He did not bike again until 1973, when he bought a road bike during a distress auction by a Houston dealer. The bike, a Dutch Magneet model, was great for exploring around Clear Lake City during the Skylab mission. He continued road biking after moving to Lexington in 1974, often taking his kids on long rides in an infant seat attached to the rear of the bike. The introduction to mountain bikes occurred in 1993, when he bought a mountain bike as a cheaper alternative to a road bike at a dealer in Toyokawa, Japan, for commuting to work and exploring during his stay there as a Nagoya University visiting professor in 1993. He bought a mountain bike on his return to Lexington and began exploring MB trails of eastern Massachusetts. Road and mountain biking continued to be a passion afterwards, and he kept MBs in New Hampshire, Columbus, Florida, and LA for use during visits. He participated in a number of sponsored 50-mile bike rides in New Mexico.
A second interest was coin collecting, set off by a Christmas gift of Whitman coin folders from his Uncle Dale Jenkins. The first goals were to fill the blank folder slots of common US copper and silver coins from circulation. This led to searching rolls of coins from the Westerville Citizens Bank and the loads of change when fellow paperboys paid their bills at the distribution center. Visits to a Columbus coin dealer introduced Stephen to Indian Head and Large Cents. Similar to biking, this hobby went dormant after high school until about 1970, when he had an income to support further collecting. Interests focused on early American coppers (New Jersey and Massachusetts colonials, large cents, half cents), and after his first visit to Russia in 1987, Russian copper and later, silver rubles. He acquired coins through many visits to Boston coin shows and catalog mail bids and became a long-time member of the Early American Copper Club and the Colonial Coin Collectors Club.
Baseball was a third interest, initiated during the 1952 and 1953 seasons not by playing the sport, but by reading the sports pages, and particularly the baseball statistics, which gave measures of player and team performance. Stephen became a fan of the Ohio teams, the Cincinnati Reds and the Cleveland Indians, and attended games every summer with his father and brother Tom while living at home in Westerville. He soon learned to score games and always kept score at the many games he attended. The loss of the World Series by the Indians in 1954 was a lifetime painful memory. The move to the San Francisco Bay Area in 1961 gave Stephen and fellow grad students opportunities to attend many San Francisco Giants and Oakland Athletics games. As an avid fan, he later attended many games in Washington, Houston, and Boston and followed game results on a daily basis. He later played on softball teams while working in Cambridge and at Hanscom AFB. In about 2005 he began an annual series of "beer, biking, and baseball" spring vacations to cities with baseball parks
His sports-minded friends 'in Berkeley took him to his first NHL game with the Oakland Seals about 1968. He gradually learned the rules and tactics of hockey and became an NHL and Boston Bruins fan upon moving to the Boston area in 1972 and began attending many games at the Boston and TD Gardens.
Genealogy was a later interest, begun in the early 1970s. Through the collection of death, birth, marriage, census, and bible records, photographs, and microfilm record searches, county and town histories, correspondence with family members, and cemetery visits, Stephen assembled material for two self-published genealogies, "The History and Descendants of John and Sarah Kahler" in 1981 and "The Ancestry and Descendants of Daniel and Susannah Strauch of Hancock County, Ohio" in 1988, both dealing with his paternal Kahler family, and an unpublished manuscript of his maternal Jenkins line, "The Descendants of George Washington Jenkins of Champaign County, Ohio and of Newman Jenkins of Mercer County, Ohio".
His most important focus was in physics, initiated in his junior year by reading popular paperbacks on astronomy and atomic physics by Fred Hoyle, George Gamow, and others. He continued on to introductory books on atomic physics while taking WHS classes in chemistry and physics. Fellow students David Deamer, King Collins, Robert and William Keller, and Jake and Sara Eberfeld shared his interests and helped form a WHS science club. He bought and experimented with various chemicals in his home basement and set off explosives constructed from gunpowder and metal tubing or pipes. Stephen read widely on astronomy and memorized the stellar constellations during the course of his junior year. After graduating from Westerville High School in 1957, he knew he wanted to study physics and astronomy. Nearby Ohio State University seemed an obvious choice
Stephen received his undergraduate education with a B.Sc. cum laude in physics from Ohio State University in 1961. He matriculated in 1957 and received 18 hours of course proficiency credits in mathematics, chemistry and English. After getting a 4.0 in his first quarter with 21 credit hours, he was assigned to Prof. Leonard Jossem of the Physics Department as his advisor. Stephen embarked on an "Individualized Plan of Study", which allowed a student to take courses without the required prerequisites and with no limits to the number of credit hours, but a 3.0 (B) GPA was required for every academic quarter to stay on the program. Besides the basic physics curriculum, he took a number of astronomy courses. He commuted daily from Westerville and became friends with math majors Herbert Doughty, William Ramaley, and Daniel Giesy. Stephen took advantage of undergraduate summer jobs at Fort Derrick, Frederick, Maryland (with his Uncle Dale Jenkins); the OSU Research Foundation in Columbus; Argonne National Laboratory in Lemont, Illinois; and Brookhaven National Laboratory, Upton, New Work, after each successive OSU school year. He also gave weekly public astronomy demonstrations at Otterbein College in Westerville and was a member of the Columbus Astronomical Society. Prof. Jossem advised Stephen to look elsewhere than OSU for graduate school to get a broader physics perspective. His applications were accepted by the University of Rochester, Harvard University Applied Physics Department, Stanford University, and the University of California at Berkeley. He selected the last one, which stood out for its high reputation and for having both large physics and astronomy departments.
After finishing work at Brookhaven Lab on Long Island in September 1961, Stephen drove across the country to San Francisco to stay with friend Steadman Thompson in San Francisco while he enrolled and found housing in the Berkeley area.
The first year at Berkeley was a very challenging year of trying to keep up with math and physics classes, acting as a teaching assistant (TA) for lab courses, as well as preparing for the physics prelim exam, which was taken and passed in the spring. Grad students became residents of California, which meant a waiver of tuition. The small TA stipend was sufficient to pay for his small cottage rental in El Cerrito and gas for the car. Stephen obtained a vacation studentship at the Rutherford Laboratory in Harwell, England during the summer of J962, his first trip to Europe. He roomed with another American student at a boarding house in Oxford, and explored England on weekends, then toured Denmark, Germany, Czechoslovakia, Switzerland, and France in his final three weeks before flying back to San Francisco from Paris via a cheap Cal student charter fright.
The 1962-1963 year involved more required physics and math courses and looking for a professor to do his thesis work. Hoping for a physics area close to astronomy, space science was a young field generously funded by NASA, and Kinsey Anderson was a young Associate Professor doing space exploration with balloon, rocket,and satellite experiments. He accepted Stephen as a student, but was a bit dismayed that Stephen had already accepted an offer of a summer job at Los Alamos Scientific Laboratory in New Mexico and would not begin working in the Anderson group until fall.
Stephen received his MSc via an oral exam in the fall 1963 and began work as a student of Kinsey Anderson, first learning about particle detectors and later to reduce data from UCB energetic proton detectors on the Orbiting Geophysical Observatories I and III, launched in September 1964 and June 1966. After several years of waiting for a suitable solar event, his first paper, dealing with a SEP event on 24 March 1966, was published in Solar Physics in 1967. He finished his PhD thesis, "The Propagation of Solar Protons", in 1968 and received his degree from UCB in February 1968. Parents Karl and Mary came to Berkeley for the commencement. He continued as a postdoc at the UCB Space Science Lab for a year after graduation, departing for NRL in March 1969. During that time, he was coauthor on three more published works on solar energetic particles.
Several memorable recollections of the VCB graduate years: (I) The 1964 Free Speech Movement was a campus wide event of which he and fellow physics grads and roommate Abe Bookstein were avid supporters. Anti-war marches were another Berkeley staple for the remaining graduate years. (2) The summer 1966 visit ofthe famous astronomer Cecilia Payne- Gaposchkin to study variable stars in the small Magellanic Cloud using the blink comparator in the UCB Astronomy Department. Her son Peter was his roommate at the time, and she stayed with them, sleeping on an uncomfortable couch in our front room. Her husband, astronomer Sergei Gaposchkin, came later in the summer and stayed a short while. He considered solar physics to be a rather pointless undertaking, sunspots being the only topic of interest. (3) Being a fast occupant of the Space Sciences Laboratory in the Berkeley Hills in 1966 after spending several years at the SSL "shoe store" facility on University Avenue in downtown Berkeley. (4) Physics seminars and work with fellow students who became well known later in the heliospheric community: Robert Lin, Jack Gosling, Hugh Hudson, George Parks, Ken Schatten, Michael Lampton, Ferdinand Coroniti, and several others.
In 1968 Stephen was recruited by Stuart Bowyer, a new researcher at the Space Science Lab, to take a post-doc position (E. O. Hulburt fellow) at the Naval Research Laboratory in Washington to work on data from a proportional counter solar X-ray detector that Bowyer had built and flown on the OGO-5 spacecraft while still at NRL. Stephen arrived in March 1969, and stayed briefly with his uncle Dale Jenkins in Washington before finding an apartment in Oxon Hill, Maryland. Girlfriend (later wife) Barbara Fritts soon joined him from San Francisco. Robert Kreplin was Stephen's advisor at NRL and he worked with John Meekins and Don Horan to render the first correct interpretation of temperatures and emission measures in solar flares. His other NRL work dealt with properties of solar X-ray flares and type III radio bursts. He spent three post-doc years at NRL and expected to be offered a permanent position, but an interview with branch chief Talbot Chubb in 1971 made clear that such a position was not a certainty, so he had to look elsewhere for his next position. At the December 1971 AAS winter meeting in San Juan. Puerto Rico, he talked to Giuseppe (Pippo) Vaiana about the solar X-ray imaging telescope that the American Science and Engineering Company in Cambridge, Mass, was preparing for the Skylab mission to be launched in 1973. Vaiana invited him to Cambridge to give a seminar on his NRL work, which he presented in spring 1972, while meeting AS&E staff members. Stephen accepted a job offer from AS&E soon afterward.
Stephen and Barbara moved to an apartment ln Boston in May 1972 as he began work at AS&E. ln preparation for the Skylab mission with the solar X-ray imaging telescope in mid-1973, they moved to Clear Lake City early in 1973. He worked at NASA JSC to train the Skylab astronauts and prepare for solar observations. Launch was in May 1973 and ran through March 1974. In the meantime, they adopted their son Kurt from a Houston agency in July, and Barbara became pregnant. After returning to the Boston area, they moved to an apartment in Watertown, Mass. in February, as Stephen began work on the Skylab data at AS&E. Daughter Karla was born on March 20. They bought a home in Lexington in September 1974.
Stephen's work at AS&E was dependent on NASA funding for Skylab data analysis, which was declining as proposals to NASA were unsuccessful. In September 1981 he took a one-year position as NRC Research Associate at Hanscom AFB, returned to AS&E for a year, and then went back to Hanscom AFB in October 1982 as a Senior Physicist in the Research Division of Emmanuel College, an AFRL contractor, working on solar energetic particles, his PhD thesis topic. From September 1989 to March 1990, he held a NAS-NRC Research Associateship at the Space Environment Laboratory, National Oceanic and Atmospheric Administration, Boulder CO and was a visiting scientist at High Altitude Observatory, NCAR, Boulder CO. During this period, he and Barbara bought a house on Judson Drive in Boulder. In April 1990 he became a Senior Research Physicist at the Institute for Space Research, Boston College, on an AFRL contract until joining as a civil servant in March 1992.
Stephen held several short-term foreign research appointments during his time at Hanscom AFB, including: (1) September 1990 - December 1990, exchange scientist for the National Academy of Science and Academy of Sciences of the USSR at the Physical-Technical Institute, Leningrad, USSR. (2) October 1994 - January 1995, Visiting Professor at Solar-Terrestrial Environment Laboratory, University of Nagoya Toyokawa, Japan. (3) March 2001 - May 2001, Air Force Window on Asia visiting scientist at Institute of Space and Aeronautical Science, Sagamihara, Japan. (4) March 2003 - May 2003, Air Force Window on Europe visiting scientist at Astrophysical Institute of Potsdam, Potsdam, Germany.
He continued work at AFRL at Hanscom AFB from 1992 until July 2011, when he joined the rest of the space physics group in the BRAC-mandated transfer to Kirtland AFB, NM. At Hanscom, his work dealt with CMEs, SEP events, coronal and interplanetary magnetic fields, and related topics. Frequent collaborators were Ed Cliver, Don Reames, Nancy Crooker, Alan Tylka, Nat Gopolswamy, Alan Ling, David Webb, Brigitte Ragot, Elena Daibog, Jack Gosling, Robert Lin. He was a member of the American Astronomical Society and the AASSolar Physics Division (Committee Member 1982-84; Nominating Committee 1984; Chair 1997-99),International Astronomical Union, American Geophysical Union, Sigma Xi scientific societies. In August 2011 Stephen arrived in Albuquerque and rented an apartment on Indian School Rd NE. He continued his work as an Air Force and Space Force government employee for the Battlefield Environment Division of the AFRL Space Vehicles Directorate.