On May 4, 1933, Bell Labs announced that one of their scientists working in the Holmdel facility had succeeded in detecting radio waves from the Milky Way galaxy, a breakthrough that signaled the birth of a new field of science now known as “radio astronomy.” And the man credited with this discovery is Karl G. Jansky, and he was yet another genius who lived among the rest of us common folk in Little Silver, New Jersey.
The impact of Karl Jansky’s discovery is almost incalculable. Overlooked at the time by both radio scientists as well as astronomers, few knew what to make of radio signals emanating from the Milky Way Galaxy. But experts would eventually recognize the importance of Jansky’s work, setting the stage for “some of the most revolutionary developments in modern science, including such discoveries as quasars, pulsars, and the glow of the fireball in which the universe was born.”
Today, Jansky is honored for his work at BellWorks, the former site of Bell Labs, where he conducted his research and worked for his entire career.
Perhaps even more impressive is a site out in the middle of the New Mexico desert, a 22-square-mile wasteland populated with 27 enormous dish antennae, mounted on a Y-shaped rail track, where they can be moved and focused anywhere in the sky. This is the Karl G. Jansky Very Large Array Radio Telescope, constructed in the late 1970s and operational in 1981.
The Early Life of Karl Jansky
Karl Guthe Jansky was born in 1905 in what was then the Territory of Oklahoma. His father, Cyril M. Jansky, was born in Wisconsin of Czech immigrants, started teaching at the age of sixteen, and was a teacher throughout his active life. He was dean of the College of Engineering at the University of Oklahoma at Norman, and retired as professor of electrical engineering at the University of Wisconsin. He was an engineer with a strong interest in physics, a trait passed on to his sons. Karl Jansky was named after Dr. Karl Eugen Guthe, a professor of physics at the University of Michigan who had been an important mentor to his father.
Karl Jansky’s mother, born Nellie Moreau, was of French and English descent. Karl’s brother Cyril M. Jansky Jr., ten years older, had a keen interest in radio from an early age. He helped build some of the earliest radio transmitters in the country, and, while a college student, helped start the experimental radio station 9XM.
From 1922 to 1925, Cyril Jansky Jr. was a member of four conferences that helped establish government radio regulation and laid the groundwork for the 1927 Radio Act, which created the Federal Radio Commission, precursor to the current FCC. It also was the first legislation to mandate that stations had to show they were “in the public interest, convenience, or necessity” in order to receive a license. Cyril Jr. also helped establish the National Association of Broadcasters. In 1930, he and Stuart Bailey, a former student, built – and then operated – W3XO, the first FM radio station in Washington, D.C., and only the third in the U.S. And Cyril would use his expertise and influence to help his brother Karl fulfill his potential as a scientist.
Karl was an athlete from a very early age who enjoyed playing hockey, baseball, and tennis, despite a kidney ailment that plagued him most of his life. As an adult, he was a competitive table-tennis player, winning Monmouth County and state honors.
Jansky attended the University of Wisconsin where he received his bachelor’s degree in physics in 1927. He stayed an extra year at Madison, completing all the graduate course work for a master’s degree in physics, except for the thesis. He applied for a job with Bell Labs, but was turned down because of his kidney ailment. But his brother Cyril, by now a well-established expert in radio science, had connections at Bell Labs and was able to provide assurances that his brother was physically up to the rigors of professional scientific research at the highest level. According to Cyril Jr.:
It so happened that ten years previously I had been a member of the staff of the Bell system Laboratories and more recently, while a member of the faculty of the University of Minnesota, I had spent summers at the Laboratories. Therefore, by chance, I happened to be in a position to argue with members of the personnel department, with whom I was well acquainted, that Karl Jansky was a good risk.
Thanks to Cyril, Bell Labs offered Karl a job in July of 1928. Owing to his condition, Karl, 22, was sent to the healthier environs of the Bell Labs field station at Cliffwood, near Matawan in Monmouth County, and then moved to the facility in Holmdel.
In 1929, Karl married Alice Larue Knapp of Evansville, Ind., at the Jansky family home in Madison, Wisc. The newlyweds first lived in Red Bank, and then moved to Little Silver.
Karl car-pooled to work with other Bell Labs scientists, including Russell S. Ohl, a man who was awarded 132 patents and is generally regarded as having invented the silicon solar cell. OH, and by the way, Ohl was Jansky’s boss. While car-pooling, Ohl and Jansky shared the progress they were making on their respective assignments, and served as a valuable sounding board for one another, such that Karl and Alice moved into a house at 57 Silverton Avenue, in the Foxwood Park neighborhood of Little Silver, immediately behind Ohl’s house at 52 Woodbine Avenue. Immediately behind his boss’s house.
Karl Jansky would go on to record five patents of his own; it’s hard to imagine two more accomplished and brilliant minds living next door to one another. Clearly, geniuses of the highest order lived throughout Monmouth County in the heyday of Bell Labs. Russell Ohl said of his friend and colleague, “Jansky was a very modest man. He was an awfully nice fellow, and I liked him very much.”
Karl was active in the Little Silver Community Club, and youth hockey, while Alice was a member of the Red Bank Women’s club. The Janskys had two children, a son, David B. Jansky, and a daughter, Anne Moreau Jansky.
Jansky’s Work at Bell Labs: Eliminating Radio Noise
In addition to being neighbors and friends, Russell Ohl was also Karl Jansky’s boss, but he was smart enough to know not to go where he was not needed. “Karl Jansky reported to me when he first came to the laboratory,” said Ohl. “But it didn’t take me long to see that he didn’t need any supervision. He was one of these persons who could stand on his own two feet and if you tried to direct a person like that, you ruined his virtues.”
Jansky was assigned the job of identifying sources of static that interfered with radio voice transmissions. Bell Labs wanted him to investigate atmospheric and ionospheric properties using “short waves” (wavelengths of about 10–20 meters) for use in trans-Atlantic radio telephone service.
He built a directional antenna designed to receive radio waves at a frequency of 20.5 MHz (wavelength about 14.6 meters). It was approximately 100 feet in diameter and 20 feet tall. It was mounted on top of a turntable on a set of four Ford Model-T wheels, which allowed it to be rotated, earning it the nickname “Jansky’s merry-go-round.” It was later estimated to have cost less than $1,000. By rotating the antenna in the azimuthal direction, the location of a received signal could be pinpointed. The intensity of the signal was recorded by an automated recording system housed in a small shed to the side of the antenna.
After recording signals from all directions for several months, Jansky eventually categorized them into three types of static: nearby thunderstorms, distant thunderstorms, and a faint static, or “hiss,” of unknown origin. He spent more than a year investigating the source of the third type of static. The location of maximum intensity rose and fell once a day, leading Jansky to initially surmise that he was detecting radiation from the sun.
After a few months of following the signal, the point of maximum static moved away from the position of the sun. Jansky determined that the signal repeated on a cycle of 23 hours and 56 minutes. He discussed the puzzling phenomena with his friend, astrophysicist Albert Melvin Skellett, who pointed out that the observed time between the signal peaks was the exact length of a sidereal day, that is, the time it took for fixed astronomical objects such as a star to pass in front of the antenna every time the earth rotated. At this point Jansky realized that the signals were coming from beyond the sun, and that the signal remained fixed within a field of stars. Jansky compared his observations with optical astronomical maps, and then, at 7:10 p.m. on September 16, 1932, Jansky concluded that the radiation was coming from the Milky Way, and was strongest in the direction of the center of the galaxy, in the constellation of Sagittarius.
Jansky continued his work in secret for another six months and wrote a paper on his research, “Electrical Disturbances Apparently of Extraterrestrial Origin,” which he presented at a meeting of the International Scientific Radio Union, a professional organization in Washington, D.C., in April 1933.
Then, on May 4, 1933, Bell Labs announced that Jansky had succeeded in detecting radio waves from the Milky Way galaxy. Even though few people had any notion of what this discovery meant – at first it was thought to be a potential new source of energy – it was still exciting enough to merit national coverage in U.S. newspapers.
Cyril Jansky Jr. was one of the few people who fully understood the momentous nature of his brother’s breakthrough:
“Electrical Disturbances Apparently of Extraterrestrial Origin,” is in effect a wedding ceremony. It weds the science of astronomy and the science of radio and electronic engineering, tying them together by inseparable bonds.
On May 16, 1933, Karl Jansky addressed the nation, demonstrating his findings to “radio listeners throughout the United States,” via the “WJZ coast-to-coast network,” i.e., the National Broadcasting Company (NBC). Jansky told the audience that they were hearing sounds that needed as much as 40,000 light-years to reach planet earth. The New York Times reported, “The sound, generated by the waves arriving at a supersensitive receiving set operated by Dr. Karl G. Jansky…sounded like steam escaping from a radiator.”
Jansky authored two more papers on his research which were published by engineering journals; his three papers from this time were found sufficient by the University of Wisconsin to finally award Karl his master’s degree.
So it was that Karl Jansky received full credit for this discovery, but as is typically the case, he was building on the work of others, who were not given credit for their contributions. For example, according to Ohl, two other Bell Labs researchers, Louis Lowry and Ed Bruce, had shared the results of their work with Ohl and Jansky, which had helped pave the way for Karl’s breakthrough work:
Bruce had found spots in the sky in which there was radio noise. The result of this was that he was, in my estimation, the first one to recognize star noise, before Jansky. He didn’t use the sharp antennas that Jansky used, and he didn’t scan the sky as thoroughly as Jansky did. He let the earth move around and let the earth’s motion move the sound across the sky. Jansky didn’t do that. He [Jansky] made the antenna go around. He would check the sky in the same spot time after time before he arrived at conclusions. He [Jansky] was really the originator of radio astronomy. Bruce and Lowry made the first observations.
After his retirement, in a series of interviews, Russell Ohl described a Bell Labs that was anything but an ideal working environment. In particular, there were internecine politics such that it was senior management and public relations executives largely deciding whose research was worthy of a patent application, whose research was worthy of publication and demonstration, and whose work was worthy of public announcement and publicity. For Karl Jansky, having strong connections beyond the walls of Bell Labs proved fruitful. According to Ohl:
Jansky got the full credit for it [the discovery of radio waves from space] because his brother was influential in the radio business. And…his brother informed the editor of Electronics magazine [who] thought this was a wonderful discovery and should be publicized and he went to [Bell Labs senior management and said] that if Bell Laboratories did not publish this work that he would publish it without any further authority in Electronics. As a result of that…it was published and that Karl Jansky was allowed to make a demonstration on radio when it was broadcast.
Ohl noted that Jansky received credit in the astronomy community, but at least one executive from Ball Labs’ senior management team tried to claim that that it was actually he who had discovered it, but Ohl said, “that isn’t true.” It is difficult to see Karl Jansky as deserving of sole credit for his discovery, but he that’s what he received.
How did this happen?
Jansky’s brother Cyril and other connections outside of Bell Labs enabled Karl to essentially by-pass his ultimate supervisor, a man named Harald T. Friis. Russell Ohl said, “The result of the whole thing when Jansky got his publicity was that his work was cut out. They stopped it. They put him on developing low noise amplifiers.”
Jansky had been keen to continue investigating these mysterious cosmic signals and wanted to build a 30-meter dish antenna for that purpose. Since Jansky’s work showed the hissing static should not be problematic for transatlantic communications, his superiors judged the project complete. Jansky was assigned to other projects and never returned to this topic. He remained at Bell Labs for the rest of his career, toiling in relative obscurity despite having pioneered a new field of science.
In the late 1930s, Jansky became increasingly involved in classified defense work, particularly related to electronic detection of submarines, for which he received an Army-Navy citation. During World War II, Jansky applied for three patents relating to radio direction location: High-Frequency direction finder, filed February 17, 1942; Three-dimension radio direction finder, filed August 30 1943; and Phase Shifter, filed November 15, 1943. Following the end of World War II, he worked on the emerging AT&T microwave repeater network for long distance telephone communication and followed with interest the rapidly developing field of radio astronomy. After the Bell Labs invention of the transistor in 1947, Jansky was one of the first to use transistors to build low noise preamplifiers and received several patents on a radio direction finder or sextant based on the radio emission from the Sun which was later developed by the Collins Radio Co. for the Naval Research Laboratory.
Early in 1950, Karl Jansky came into Russell Ohl’s office, and Ohl thought Jansky seemed to be sick. Karl told him, “I’ll have to say good-bye to you. I’m very seriously ill and must go to the hospital.” Ohl put his arms around him and said, “I hope you’ll be able to come back and see us soon. That was one of the saddest moments of my life.”
Karl G. Jansky died on February 14, 1950, age 44, from complications arising out of his lifelong kidney ailment.
The Legacy of Karl G. Jansky
The ultimate impact of Jansky’s research was discovering that radio astronomy could be used to gather information about astronomic objects beyond the reach of visual astronomy. As Cyril Jr. later recalled, “The scientist’s problem is to recognize basic facts even though they are obscured by a wealth of extraneous material, and then to apply creative imagination in their interpretation. This Karl Jansky did.”
When Jansky’s first 1933 paper was reprinted in Proceedings of the IEEE in 1984, the editors noted that Jansky’s work would mostly likely have won a Nobel prize, had the scientist not died so young.
Scientists have continued to build on the breakthrough work of Karl G. Jansky. As just one example, on October 17, 1978, Arno Penzias and Robert Wilson, researchers at Bell Labs in Holmdel, were recipients of the Nobel Prize in Physics for their discovery of cosmic microwave background radiation. Using the powerful “Holmdel horn antenna,” Penzias and Wilson gathered the first experimental evidence that established the “Big Bang” model of the origin of the universe.
Today, the “jansky” is the unit of measurement for “flux density,” that is, the intensity of extraterrestrial radio waves. A crater on the moon is named after him, and of course there is the Very Large Array. The Karl G. Jansky Very Large Array Radio Telescope in New Mexico is the most advanced radio telescope array on earth, a “customizable interferometer that spans up to 22 miles across.” It is a familiar sight to movie fans as one of the primary locations for the 1997 Jodie Foster movie Contact.
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Jansky, Cyril M. Jr. (1953). Letter to Professor John S. Penn, June 23, 1953. Wisconsin Center for Film & Theater Research, University of Wisconsin-Madison. Available: https://wcftr.commarts.wisc.edu/sites/wcftr.commarts.wisc.edu/files/exhibits/files/2015/02/08/Jansky.pdf.
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