Skip to Content Skip to Search Skip to Utility Navigation Skip to Top Navigation Skip to Content Navigation
Los Alamos National Laboratory

Los Alamos National Laboratory

Delivering science and technology to protect our nation and promote world stability

In Memoriam Archive

Honoring Los Alamos National Laboratory Fellows and their contributions to the institution.


Arthur Nelson Cox

Arthur Nelson CoxArthur Nelson Cox

(October 12, 1927-March 12, 2013)

Arthur Nelson Cox, noted astrophysicist, author and editor, beloved husband, father, grandfather and great-grandfather, died peacefully in his sleep on March 12, 2013 at St. Vincent's Hospital in Santa Fe. He was 85.

Arthur was born on Oct. 12, 1927 in Van Nuys, Calif. to Arthur H. Cox and Sarah Nelson Cox, he was the third of their four children. He was preceded in death by his younger brother Donald, his older sisters Marjorie-Jane and Priscilla, Joan Cox, his wife of 32 years, and Joan's son Bryan Johnson.

Arthur is survived by Charles Arthur Cox and Edward Jonathan Cox, two sons from his first marriage to Clarice W. Cox; and by Charles' wife Anna Ratner and their children Bryan and Maya; Edward's fiance Phillis Tyler; their children, spouses, grand and great- grandchildren from his second marriage to Joan Cox; Kay and Brian Newnam, their son Michael and his wife Catherine; Sally and Jeff Bustamante and their children Chris Hills and his wife Mar; Benjamin Hills and his daughter Audrianna and fiance Carla Fuenzalida; Amy Hills, Jeffrey Bustamante and his wife Katrina and young son Bryan; his wife for the last two years Margaret Jaramillo Cox and her son Anselmo Jaramillo.

After growing up during the depression era in Van Nuys, Arthur took an interest in Astronomy and Astrophysics, obtaining degrees from California Institute of Technology at Pomona and at Indiana University. Following a student internship starting in the late 1940's, he began a long career with the Los Alamos Scientific Laboratory in 1955. Eventually he became a group leader for the laboratory's nuclear weapons testing efforts. In later years Arthur researched at the Laboratory in more theoretical astrophysics where he prepared numerous technical research papers regarding stellar pulsations and related subjects. Among his many accomplishments, he became a Fellow of the Laboratory and continued to be involved with these activities even in his last days.

Arthur will be remembered for many things: his contributions to science, his endless desire for adventure, his sense of humor, and his appreciation of music and the arts. His steadfast work ethic produced many years of quality research that advanced the field of astrophysics. With enthusiasm and leadership, he mentored and inspired many young up-and-coming scientists and made significant contributions in the field of stellar pulsations. His kind and gregarious nature brought smiles to everyone's faces.

Arthur Nelson Cox will be missed; there will be a special place for him among the stars above as he departs this earth and leaves us with many fond memories.


Art (Arthur Nelson) Cox was born in Van Nuys, California in 1927 where he also received his early schooling. He attended the California Institute of Technology, receiving a B.S. degree in 1948. Art had his first association with the Los Alamos Scientific Laboratory (now the Los Alamos National Laboratory) in his junior year when he took a job helping to assemble model 100 amplifiers with the (then) amazing rise time of 0.7 microsecond.He returned the summer after graduation to assist in the cyclotron group with measurement of thermonuclear reaction rates. These early connections with the lab continued through the remainder of his career.

Art went to Indiana University in 1949 to pursue an education in astronomy. In those days the Astronomy Department consisted of four faculty members and about six to eight graduate students. Art was the first to pursue and receive a Ph. D. in astronomy from the department in “modern times.” In this role, Art really served as the model for his fellow students. He was the archetypical hard working graduate student. Art served as research assistant to the late Professor John Irwin. Art went to the Cape Observatory with John for a number of months to make photometric observations of star clusters and variable stars. These observations served as the material for his doctoral thesis, A Study of the Galactic Cluster NGC 2287, and the photometry of variable stars set a precedent for his continuing interest in variable stars throughout his career.

After receiving his doctorate in 1953, Art went directly to the Lab where he joined the J Division. J Division was the organization charged with conducting the field tests of atomic weapons as well as many aspects of the preparations and analysis of such work. Among Art’s early assignments was to assist in the design of the experiment that would test some of the first thermonuclear devices in the Marshall Islands. He subsequently became the leader of group J-15 and continued in that position for almost 18 years. Originally, J-15 consisted of about four staff members and four technicians. With Art’s astronomical background, he recruited several fellow astronomers over the years for the staff jobs. These included Robert Brownlee, Thomas Swihart, Paul Mutschlecner, and Charles Keller, all coincidentally with astronomy Ph.D.s from Indiana University! This astronomy connection actually made a lot of sense, for much of the training in astronomy was appropriate to the needs of J-15. Art presided over an incredible diversity of research in the group. The work included, in addition to the test work, modeling of fireball effects, observation and modeling of underground nuclear tests, design and use of equation of state and opacity codes, and a program in the observation of oceanic tsunamis.

Along the way Art managed skillfully to include his interests in astrophysics. Art organized airborne solar eclipse expeditions to Samoa in 1965, Argentina in 1966, Mexico in 1970, Canada in 1972, Africa in 1973, and Montana in 1979. The marvelous approach to this work was that he was able to draw upon the theoretical and experimental expertise of a variety of scientists at the Lab and elsewhere, and to utilize the facilities of the U.S. Air Force, which was charged with support for readiness in any future nuclear tests. The eclipse campaigns helped them to maintain their readiness! Art also began his lifelong work on the modeling of various types of variable star models and of solar models. Here Art was able to exploit the ever-increasing computing resources of the Lab.

In 1975 Art joined T Division, the theoretical organization of the Lab, where he remained [until retirement and continued as an affiliate until his death in 2013]. In this new position Art was able to concentrate nearly exclusively on astrophysical problems. His interests that he pursued with a number of colleagues, both at the Lab and in the international community, have included stellar pulsation theory, stellar and solar seismology, astrophysical opacities and variable stars in general. Art has written and co-authored papers on all classes of variable stars. In recognition of his work Art served as the President of International Astronomical Union Commission 35 (Stellar Constitution) from 1982 to 1985. Art was recognized for his many contributions to science and to the Lab by being selected as a Laboratory Fellow in 1983, and he also served as coordinator of the Laboratory Fellows in 1986-1988.

Although Art retired from the Lab in the mid 1990s, he remained fully active in astrophysics. Recent activities have included the editing of the book The Solar Interior and Atmosphere, and editing a new, and badly needed, revision of Astrophysical Quantities.

Art has received many honors in recognition of his work. He served on numerous national and international committees and panels on astronomy. In 1968 he was a Senior NATO Fellow at Liege, Belgium and was a Fullbright Research Scholar from 1968 to 1969. He was awarded an honorary D.Sc. from Indiana University in 1973. He also served as NSF Astronomy Program Director from 1973 to 1974.

Written by J. Paul Mutschlecner and David S. King in 1997 for the conference, A Half Century of Stellar Pulsation Interpretations: A Tribute to Arthur N. Cox, eds. P.A. Bradley and J.A. Guzik. At the time, Paul Mutschlecner and David King had been friends and colleagues of Art Cox for a cumulative total of over 80 years.

Dimitri Mihalas

Dimitri MihalasDimitri Mihalas

(March 20, 1939 - November 21, 2013)

World-renowned astrophysicist Dimitri Mihalas passed away in his sleep at his home on November 21, 2013 in Santa Fe, New Mexico. Dr. Mihalas retired from the University of Illinois at Urbana-Champaign in 1999 and from the Los Alamos National Laboratory in 2011. Dimitri, to his friends and family, has donated his body to the University of New Mexico Medical School and his library to New Mexico Tech.

Dimitri was born on March 20, 1939 in Los Angeles, California where he grew up. He received his B. A., with Highest Honors, in three majors: Physics, Mathematics, and Astronomy from the University of California at Los Angeles at age 20. Four years later he received his Ph. D in Astronomy and Physics from the California Institute of Technology. He then joined the faculty of the Department of Astrophysical Sciences at Princeton University. In the following three decades, he was a professor in the Department of Astronomy at the University of Chicago, the University of Colorado at Boulder, and the University of Illinois at Urbana-Champaign. He was also a pioneer in astrophysics and computational physics and remained a world leader in the fields of radiation transport, radiation hydrodynamics, and astrophysical quantitative spectroscopy for most of his career. His broad knowledge and immense contributions earned him election to the U.S. National Academy of Sciences in 1981 (at age 42, fifteen years earlier than the usual age of entry) and many other distinguished awards. He was a laboratory fellow at the Los Alamos National Laboratory.

Dimitri had an exceptional record of both quantity and quality of work, and developed new and far-reaching methodologies yielding results of great importance. He made outstanding contributions to the field of Astronomy and Astrophysics. Besides many high-quality papers, he authored or co-authored seven books and co-edited three others. Among them, three of his books have been used as textbooks for both undergraduate and graduate students worldwide and translated into other languages such as Russian and Chinese. His book Foundations of Radiation Hydrodynamics has become the “bible” of the radiation hydrodynamics community, especially at Los Alamos and Lawrence Livermore National Laboratories and the Naval Research Laboratory.

Dimitri’s colleagues and graduate students held him in high appreciation and expressed their admiration for him at the International Conference in Honor of Dimitri Mihalas for his Lifetime Scientific Contributions on the Occasion of his 70th Birthday held at Boulder in late March 2009. A symposium was published following the conference.

Throughout his long career, Dimitri gave generously of himself to all with whom he interacted. As an advisor, role model, confidant, and friend, he saw each person as an individual, acknowledging strengths, helping overcome weaknesses, giving encouragement, and enthusiastically praising their success. He touched the lives and careers of many students and colleagues and has left a lasting legacy to be cherished by those who knew him.

Stirling Colgate

Stirling ColgateStirling Colgate

(November 14, 1925 - December 1, 2013)

Laboratory Senior Fellow and longtime Laboratory scientist Stirling Colgate of Nuclear and Particle Physics, Astrophysics and Cosmology (T-2) died Sunday (Dec. 1) at his home in White Rock. A co-founder of the Santa Fe Institute, Colgate, 88, also was president of the New Mexico Institute of Mining and Technology in Socorro from 1965 to 1974 and a professor emeritus of physics at the school.

A gathering, "Remembering Stirling," open to colleagues and friends is scheduled for 5:45 p.m., Sunday, Dec. 15, at Fuller Lodge.

"Los Alamos has lost a tremendous scientist, colleague, mentor and friend," said Director Charlie McMillan. "His contributions to physics and national security science, including some very recent work, are broad, deep and exceptionally creative. On behalf of the Lab, I offer our deepest condolences to Stirling's family."

"He was an incredibly nice guy. It was a quality most people didn't see in him," noted Laboratory Fellow James L. Smith of Materials Technology/Metallurgy (MST-6). "[Stirling] really loved having young people around who wanted to talk to him. He really cared about helping young people."

"I think Stirling was a fantastic mentor to students and postdocs," said Theoretical (T) Division Leader Tony Redondo. "His office was always full of young people who were very excited to have discussions with him. Stirling always had very interesting ideas."

Colgate was born Nov. 14, 1925 in New York City. He attended the Los Alamos Ranch School until 1942 when the school closed in the run-up to the Manhattan Project. Colgate served two years in the Merchant Marines before attending Cornell where he earned bachelor's (1948) and doctoral degrees in physics (1951). He worked at Lawrence Livermore National Laboratory from 1952 to 1965; his career at both LANL and LLNL totaled 50 years.

Colgate came to then Los Alamos Scientific Laboratory in September 1976 where he worked in various groups in Theoretical (T) Division. He was named a Senior Laboratory Fellow in 1987. From late 2008 to the present, Colgate was a Lab associate Fellow in T-2. Colgate was a member of the National Academy of Sciences. More recently, Colgate and Hui Li, of T-2, were co-principal investigators of a LDRD project that involved experimental work at New Mexico Tech involving astrophysical phenomena and turbulence.

Colgate is survived by his wife Rosie; a son and a daughter; four granddaughters; a great-grandson; and sister Anne Sutton of Honolulu.

Descriptive Vita

Visit Blogger Join Us on Facebook Follow Us on Twitter See our Flickr Photos Watch Our YouTube Videos Find Us on LinkedIn Find Us on iTunesFind Us on GooglePlay