Jules Fejer ( hu, Fejer Gyula Endre; 22 January 1914 – 21 December 2002) was a Hungarian-born physicist. Fejer was born in

Budapest Budapest (, ; ) is the capital and most populous city of Hungary. It is the ninth-largest city in the European Union by population within city limits and the second-largest city on the Danube river; the city has an estimated population ...

Austria-Hungary Austria-Hungary, often referred to as the Austro-Hungarian Empire,, the Dual Monarchy, or Austria, was a constitutional monarchy and great power in Central Europe between 1867 and 1918. It was formed with the Austro-Hungarian Compromise of ...

on 22 January 1914, son of Ernest Fejer and Stella Popper. As an engineer with South Africa's National Institute for Telecommunications Research (NITR), He published the first estimate of the life expectancy of the recently launched Sputnik in

Nature Nature, in the broadest sense, is the physical world or universe. "Nature" can refer to the phenomena of the physical world, and also to life in general. The study of nature is a large, if not the only, part of science. Although humans are ...

. His prediction was far more accurate than those made by the Russians, British and Americans. In the late 1950s he wrote a fundamental paper on incoherent

backscatter In physics, backscatter (or backscattering) is the reflection of waves, particles, or signals back to the direction from which they came. It is usually a diffuse reflection due to scattering, as opposed to specular reflection as from a mirror, a ...

, explaining why the width of the backscattered echo was determined primarily by the ion thermal velocity rather than by the electron thermal velocity. He was one of a group of ionospheric physicists brought together by Henry G. Booker to start what became the Electrical and Computer Engineering department at the

University of California, San Diego The University of California, San Diego (UC San Diego or colloquially, UCSD) is a public land-grant research university in San Diego, California. Established in 1960 near the pre-existing Scripps Institution of Oceanography, UC San Diego is t ...

. He was elected a Fellow of the

American Geophysical Union The American Geophysical Union (AGU) is a 501(c)(3) nonprofit organization of Earth, atmospheric, ocean, hydrologic, space, and planetary scientists and enthusiasts that according to their website includes 130,000 people (not members). AGU's a ...

in 1990 and continued work with graduate students until 1995.

References

{{DEFAULTSORT:Fejer, Jules 1914 births 2002 deaths 20th-century Hungarian physicists Fellows of the American Geophysical Union Hungarian expatriates in the United States