Antony Fraser-Smith, expert in low-frequency electromagnetic variations in the Earth’s environment and in space, has died

Antony Fraser-Smith, research professor emeritus in the departments of Electrical Engineering and Geophysics at Stanford University, whose work included groundbreaking insights into the fields of radio seismology and electromagnetic methods of submarine detection, died June 16, 2025. He was 86.

Fraser-Smith’s academic career began in 1961 at the University of Auckland, where he worked as a lecturer in physics, teaching courses in general and advanced electromagnetism, generalized mechanics and special relativity, and experimental statistics and error.

In 1966, faced with limited access to the equipment he needed, he left New Zealand and joined Lockheed’s Research Laboratory in Palo Alto as an associate research scientist. There, he conducted experimental and theoretical research into the origin and properties of ultra-low frequency geomagnetic pulsations, and was responsible for the operation of the Lockheed Palo Alto Geomagnetic Observatory.

In 1968, Fraser-Smith joined Stanford University’s Radioscience Laboratory, which was renamed in the early 1980s to become the Space, Telecommunications, and Radioscience (STAR) Laboratory in the Department of Electrical Engineering. There, he worked as a research assistant, senior research associate in electrical engineering, then finally as professor of electrical engineering and of geophysics alongside colleagues that included Ronald Bracewell, Robert Helliwell, Oswald Garrison “Mike” Villard Jr., and former STAR Lab Director Umran Inan. Over the next 35 years at Stanford and around the world, Fraser-Smith investigated low-frequency electromagnetic fields, probing how they might be used to study the interior of Earth and the space environment near Earth, to identify changes in those environments, and to communicate with and detect objects submerged in the sea or deep in the ground. His projects included a global extremely low frequency (ELF)/very low frequency (VLF) radio noise measurement program; the analysis of low-frequency electromagnetic noise data from electron beam experiments on high-altitude rockets and Space Shuttle orbiters; and experimental and theoretical work in the new field of radio seismology.

“Tony was a very valuable member of our research group,” Inan says. “He loved the mystery of ultra-low frequency (ULF), because it’s an obscure area, and there are a countable number of people on the planet who understand these things. One of his projects involved running a huge wire around Chappaquiddick Island on the East Coast, and using the island itself as an antenna to create low-frequency waves that could communicate with submarines. He was a very versatile guy. But I think his earthquake work excited him the most, because it had tremendous social application potential.”

On Oct. 5, 1989, Fraser-Smith and his research team were monitoring ULF radio waves in a remote location in the Santa Cruz Mountains as part of a long-term study of electromagnetic signals reaching Earth from space. A sudden signal increase occurred, remaining in place for the next 12 days before surging even higher on Oct. 17. Three hours later, the 6.9-magnitude Loma Prieta earthquake hit the central coast of California, causing 63 deaths and more than 3,700 injuries.

After ruling out equipment malfunction, Fraser-Smith and his team wondered if the quake had announced its imminent arrival, and whether they had fortuitously been in the right place at the right time.

“Most scientists necessarily make measurements on small earthquakes because that’s what occurs all the time,” he said at the time. “To make a measurement on a large earthquake, you have to be lucky, which we were.”

Fraser-Smith and his research team – along with other academics worldwide – went on to study the phenomenon of detectable electromagnetic surges prior to large earthquakes throughout the 1990s. He largely ended his involvement in the project in the 2000s, however, due to the difficulty of anticipating where the next large temblor would occur and a lack of funding.

Fraser-Smith received his joint appointment to Stanford’s Department of Geophysics in 1992, and served as associate chair of the Electrical Engineering Department from 1995 to 2000, during which time he also oversaw graduate admissions. He took emeritus status in 2003.

During his time at Stanford he also served on the advisory panel for the Overhead Power Line Project for the State of New York (1981-87); as chairman of the Russian Earthquake Prediction Evaluation Study, Environmental Working Group, U.S.-Russian Joint Commission on Economic and Technological Cooperation (1995-97); and was responsible for the first measurements of ultra-low frequency geomagnetic field fluctuations with a superconducting magnetometer. That work led to several new discoveries, including the understanding that the DC-powered Bay Area Rapid Transit (BART) system is a prolific source of ULF magnetic field variations throughout the San Francisco Bay Area and beyond; that trees can be used as ULF antennae; and that thunderstorms are a major source of ULF magnetic field fluctuations.

“Tony was one of the leading scientists in the experimental study of Earth’s magnetic field,” says Howard Zebker, the Kwoh Ting Li Professor in the School of Engineering and professor of geophysics in the Stanford Doerr School of Sustainability. “Those who do go into the field often come at it from a theoretical standpoint, but he was one of the few people who did this work from the experimental side. He stands out as an experimental geophysicist and engineer in ways that many others do not. He was one of the primary people working in this area.”

Fraser-Smith also made time to teach, with courses including Planetary Exploration, Electromagnetic Waves, and Introduction to the Space Environment.

“As research faculty, he wasn’t required to teach, but he always did,” says Zebker. “He enjoyed working with students, and he loved the university atmosphere. I don’t think he’d have liked being squirreled away in a secret laboratory somewhere doing things, even if the technology might have been interesting. He was gregarious and liked talking with people and students.”

Fraser-Smith was the author of over 150 technical papers, and a fellow of the Institute of Physics (London) and the Geological Society of America, as well as a senior member of the Institute of Electrical and Electronics Engineers.

“Unlike some fields in electrical engineering, where things have a start and an end, much of Tony’s work tended to raise more questions than answers, and was – in some ways – an endless endeavor, which he liked,” Inan says. “Conversations with him would never end in a logical stopping point; there would always be new ideas that came to mind that needed to be further explored. And everyone in the conversation knew that and enjoyed it.”

Antony Charles Fraser-Smith was born July 7, 1938, in Auckland, New Zealand. He earned his bachelor’s degree (1959) and master’s degree (1961) in physics at the University of New Zealand, and went on to earn his doctorate at the University of Auckland in 1966.

Fraser-Smith was predeceased by his son, Bill Frasersmith. He is survived by his wife of 57 years, Elizabeth (Betsy), daughter Julie Fagan, daughter-in-law Linh Frasersmith, sister Mary Browne, and grandchildren Maizie, Chloe, and Elyse Fagan and Ryan, Kyle, and Tyler Frasersmith.