Ivan I. Mueller

Ivan Istvan Mueller (9 January 1930, Budapest – 12 April 2023, Bloomfield, Connecticut) was a Hungarian-American geodesist and professor at Ohio State University, a leading training center for geodesy in the USA.

Biography Ivan I. Mueller and his wife Marianne were married in 1950. He, with his family, left Hungary immediately after the Hungarian Revolution of 1956. Upon the recommendation of his thesis advisor, Veikko Heiskanen, Mueller was appointed to a faculty position at Ohio State University

Mueller shaped satellite geodesy from its beginnings and, in particular, designed several projects for intercontinental networks of satellite triangulation. One such project (1973/74) involved the use of Doppler instrumentation aboard satellites and is considered groundbreaking. The project's innovations were combined with the Worldwide Geometric Satellite Triangulation Program, with Hellmut Schmid as technical director, to produce the most accurate coordinate determination to date across all seas and achieved a standard deviation of approximately ±3 m, which was about 20 times more accurate than the terrestrial methods, which at the time required extremely lengthy measurements over island chains.

Another among Mueller's many ideas and projects involved Satellite Laser Ranging (SLR) to investigate the geodynamics of California. Mueller proposed that for geodynamics and geodesy, instead of recording laser-distance measurements solely from numerous ground stations using signal-relaying satellites, a considerable improvement would be to integrate the ground stations with the development of an active laser-carrying satellite system with time-of-flight measurement on board. This could result in significant improvements in measurements in terms of speed and accuracy. The idea had some problems with technical feasibility, but was adopted in a similar form around 1990 for the French DORIS Doppler measurement system.

At Ohio State University, Mueller was the thesis advisor for 25 doctoral students. He was the author or coauthor of 5 books and more than 220 scientific articles. became a standard text. He served as an associate editor for the Journal of Geophysical Research and from 1975 to 1987 as editor-in-chief of the Bulletin Géodésique (now merged into the Journal of Geodesy).

Mueller was elected in 1978 a Fellow of the American Geophysical Union (AGU),

Ivan and Marianne Mueller greatly enjoyed opera, as well as orchestral and chamber music. Upon his death in 2023, he was survived by his widow, their two daughters, and four grandchildren. 2nd edition 1977; 615 pages)