Rutherford "Gus" Aris (September 15, 1929 - November 2, 2005) was a chemical engineer, control theorist, applied mathematician, and a Regents Professor Emeritus of Chemical Engineering at the University of Minnesota (1958-2005). Over the course of his long academic career, Aris was a visiting professor at many institutions, including Cambridge University, the California Institute of Technology, and Princeton University; he authored 13 books and more than 300 chemical engineering research articles, and mentored 48 Ph.D. and 20 M.S. graduate students. Aris was well known for his research on mathematical modeling, chemical reactor and chemical process design, and distillation techniques, as well as his paleographic research. After he had been department head for four years, in 1978 he was named Regents Professor. Some of the awards and honors earned by Aris include a Guggenheim Fellowship, election to the National Academy of Engineering in 1975 and the American Academy of Arts and Sciences in 1988. Aris was also a member of the American Chemical Society, the Society for Mathematical Biology, and the Society of Scribes and Illuminators, among others. Aris was awarded the Richard E. Bellman Control Heritage Award in 1992 for his contributions to the field of control theory. He was awarded the Neal R. Amundson Award for Excellence in Chemical Reaction Engineering by the International Symposia on Chemical Reaction Engineering in 1998. In 2016, the board of the ISCRE (International Symposia on Chemical Reaction Engineering) established the Rutherford Aris Young Investigator Award for Excellence in Chemical Reaction Engineering. This award honors young researchers under the age of 40 to recognize outstanding contributions in experimental and/or theoretical reaction engineering research. Inventing Tomorrow, Winter 2006 (vol 30 no 1) Published on Dec 1, 2006; College of Science and Engineering at the University of Minnesota Rutherford "Gus" Aris, Regents Professor Emeritus of Chemical Engineering, died Nov. 2, 2005, in Edina, Minn. He was 76. He held a joint appointment in the Department of Classical and Near Eastern Studies, where he conducted research and taught classes in paleontology. A brilliant scholar, Aris had an enormous impact on the field of chemical engineering through his research, publications, teaching, and advising. Among his most important contributions are detailed explanations for sudden temperature runaways and oscillating behavior of processes involving chemical reactions, work that led to improved design of potentially explosive chemical processes and safer industrial operations. He led the way in developing new mathematical techniques for optimizing and controlling chemical manufacturing processes and in teaching these new methods to students and professional engineers. He published 13 books and more than 300 research articles, and mentored more than 65 master’s and Ph.D. students. Born in Bournemouth, U.K., on Sept. 15, 1929, Aris completed the requirements for an honors degree in mathematics from the University of London at age 16, but the university did not think it was proper to award a degree to someone so young and delayed giving Aris the degree until he was 19. He later received external Ph.D. and D.Sc. degrees from the University of London. Aris was hired in 1958 as an assistant professor by Neal Amundson, then head of the University of Minnesota’s chemical engineering and materials science department, who had a keen eye for talent. In 1974 Aris succeeded Amundson as department head and served in that capacity until 1978. Aris was elected to the National Academy of Engineering (1975) and to the American Academy of Arts and Sciences (1988). He received many honorary degrees and distinguished lectureships and more than a dozen prestigious awards from engineering and scientific societies.