Electrical engineering professor Robert Helliwell AB ’42 ENG ’44 Ph.D. ’48 died May 3 in Palo Alto at the age of 90 of complications from dementia.
Born in 1920 in Red Wing, Minn., Helliwell moved to Palo Alto with his mother after his father died. He earned his bachelor’s, master’s and doctoral degrees from Stanford and joined the electrical engineering faculty in 1946.
Helliwell is most famous for his research in how radio waves interact with charged particles in the atmosphere. He embarked on this research topic by chance in 1950, when a graduate student monitoring radio waves from distant lightning heard strange whistling noises from a speaker and later mentioned them to Helliwell. These noises, termed “whistlers,” were a result of very low frequency radio waves.
He later applied this phenomenon to make fundamental discoveries about how radio waves could be used to study the ionized atmosphere high above the earth’s surface. When electrical noise from the city power lines near Stanford interfered with his effort to detect natural whistlers, Helliwell traveled to Antarctica, where he established a research site in 1957.
The Stanford Radio Science Laboratory conducted ionospheric and magnetospheric experiments at Siple Station from 1971 until it closed in 1988. Today, Stanford graduate students in the VLF Group are still analyzing data from that research. Helliwell also wrote what is considered a classic work on whistlers, “Whistlers and Related Ionospheric Phenomena.” He is the namesake for the Helliwell Hills, an Antarctic mountain range along the coast of Victoria Land on the Ross Sea.
Helliwell’s distinguished career was decorated with the Antarctic Service Medal in 1966 and the Appleton Prize of the Royal Society of London in 1972 for his work in ionospheric physics. He was a member of the National Academy of Sciences, fellow of the American Geophysical Union and chaired one of the commissions of the International Union of Radio Science (URSI).
A memorial service for Helliwell will be held June 7 at 3 p.m. in Memorial Church.
— Ivy Nguyen