Karl Jansky

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pages: 492 words: 149,259

Big Bang by Simon Singh

Albert Einstein, Albert Michelson, All science is either physics or stamp collecting, Andrew Wiles, anthropic principle, Arthur Eddington, Astronomia nova, Bletchley Park, Boeing 747, Brownian motion, carbon-based life, Cepheid variable, Chance favours the prepared mind, Charles Babbage, Commentariolus, Copley Medal, cosmic abundance, cosmic microwave background, cosmological constant, cosmological principle, dark matter, Dava Sobel, Defenestration of Prague, discovery of penicillin, Dmitri Mendeleev, Eddington experiment, Edmond Halley, Edward Charles Pickering, Eratosthenes, Ernest Rutherford, Erwin Freundlich, Fellow of the Royal Society, Ford Model T, fudge factor, Hans Lippershey, Harlow Shapley and Heber Curtis, Harvard Computers: women astronomers, heat death of the universe, Henri Poincaré, horn antenna, if you see hoof prints, think horses—not zebras, Index librorum prohibitorum, information security, invention of the telescope, Isaac Newton, Johannes Kepler, John von Neumann, Karl Jansky, Kickstarter, Louis Daguerre, Louis Pasteur, luminiferous ether, Magellanic Cloud, Murray Gell-Mann, music of the spheres, Olbers’ paradox, On the Revolutions of the Heavenly Spheres, Paul Erdős, retrograde motion, Richard Feynman, scientific mainstream, Simon Singh, Stephen Hawking, Strategic Defense Initiative, the scientific method, Thomas Kuhn: the structure of scientific revolutions, time dilation, unbiased observer, Wilhelm Olbers, William of Occam

Radio astronomy was opening up a new window onto the universe, discovering entirely new objects and providing critical evidence in the Big Bang versus Steady State debate. Regrettably, Karl Jansky, the father of radio astronomy, received virtually no credit during his lifetime for inadvertently inventing the radio telescope and for making the first radio observations of the sky. He passed away in 1950 at the age of just forty-four. It was only in the decade after his death that radio astronomy would establish itself as a truly major discipline within astronomy. However, Karl Jansky was eventually immortalised. In 1973 the International Astronomical Union recognised his contribution by naming the unit of radio flux in his honour.

AT&T was anxious to keep a grip on this lucrative market by offering a high-quality service, so it asked Bell Laboratories to undertake a survey of the natural sources of radio waves, which were interfering with long-distance radio communication by causing a background crackling noise. The task of surveying these annoying radio sources fell to Karl Jansky, a twenty-two-year-old junior researcher who had only just graduated in physics from the University of Wisconsin, where his father had been a lecturer in electrical engineering. Radio waves, like waves of visible light, are part of the electromagnetic spectrum. However, radio waves are invisible and have wavelengths that are much longer than those of visible light.

Jansky, however, was determined to get to the bottom of the mystery and spent several more months analysing the baffling interference. Gradually, it emerged that the hiss came from a particular region of the sky and that it peaked every 24 hours. Actually, when Jansky looked at his data more carefully, he found that the peak came every 23 hours and 56 minutes. Almost a full day between peaks, but not quite. Figure 92 Karl Jansky makes adjustments to the antenna that was designed to detect natural sources of radio waves. The Ford Model T wheels are part of the turntable that allowed the antenna to rotate. Jansky mentioned the curious time interval to his colleague Melvin Skellet, who had a Ph.D. in astronomy and who was able to point out the significance of the missing four minutes.


pages: 476 words: 118,381

Space Chronicles: Facing the Ultimate Frontier by Neil Degrasse Tyson, Avis Lang

Albert Einstein, Apollo 11, Apollo 13, Arthur Eddington, asset allocation, Berlin Wall, Boeing 747, carbon-based life, centralized clearinghouse, cosmic abundance, cosmic microwave background, dark matter, Gordon Gekko, high-speed rail, informal economy, invention of movable type, invention of the telescope, Isaac Newton, James Webb Space Telescope, Johannes Kepler, Karl Jansky, Kuiper Belt, Large Hadron Collider, Louis Blériot, low earth orbit, Mars Rover, Mars Society, mutually assured destruction, Neil Armstrong, orbital mechanics / astrodynamics, Pluto: dwarf planet, RAND corporation, Ronald Reagan, Search for Extraterrestrial Intelligence, SETI@home, space junk, space pen, stem cell, Stephen Hawking, Steve Jobs, the scientific method, trade route

Lacking this extended vision, we would be not only blind but ignorant, because many astrophysical phenomena reveal themselves only in certain “windows” within the spectrum. Let’s peek at a few discoveries made through each window to the universe, starting with radio waves, which require very different detectors from those found in the human retina. In 1931 Karl Jansky, then employed by Bell Telephone Laboratories and armed with a radio antenna he himself built, became the first human to “see” radio signals emanating from somewhere other than Earth. He had, in fact, discovered the center of the Milky Way galaxy. Its radio signal was so intense that if the human eye were sensitive only to radio waves, then the galactic center would be one of the brightest sources in the sky.

When radio emissions from Saturn were discovered, for instance, it was simple enough for astronomers to hook up a radio receiver equipped with a speaker; the signal was then converted to audible sound waves, whereupon more than one journalist reported that “sounds” were coming from Saturn, and that life on Saturn was trying to tell us something. With much more sensitive and sophisticated radio detectors than were available to Karl Jansky, astrophysicists now explore not just the Milky Way but the entire universe. As a testament to the human bias toward seeing-is-believing, early detections of radio sources in the universe were often considered untrustworthy until they were confirmed by observations with a conventional telescope.


pages: 194 words: 63,798

The Milky Way: An Autobiography of Our Galaxy by Moiya McTier

affirmative action, Albert Einstein, Arthur Eddington, Burning Man, Cepheid variable, cosmic microwave background, cosmological constant, dark matter, Eddington experiment, Edward Charles Pickering, Ernest Rutherford, Harlow Shapley and Heber Curtis, Harvard Computers: women astronomers, heat death of the universe, Henri Poincaré, Higgs boson, Isaac Newton, James Dyson, James Webb Space Telescope, Karl Jansky, Kickstarter, Large Hadron Collider, Magellanic Cloud, overview effect, Pluto: dwarf planet, polynesian navigation, Search for Extraterrestrial Intelligence, Stephen Hawking, the scientific method

Remember, this was long before your astronomers even knew they lived in a galaxy, let alone that they shared it with a hateful, churning mass that lurks in the shadows of my guilt, waiting to corrupt and swallow anything that gets too close. Your astronomers just named it after the patch of sky where they detected Sarge’s signal, so any similarity in the name is merely coincidence. It’s actually a funny little human story that started with this man named Karl Jansky. Nowadays, Karl is considered the “father of radio astronomy” and he even has his own unit named after him. The jansky measures flux density, or the amount of energy passing through a specific area in a given amount of time and then normalized by the bandwidth of the telescope receiver. There are other units of flux density used in other human sciences, but the jansky is a special unit that’s useful only for exceptionally dim and small sources with broad continuum emission.


Wonders of the Universe by Brian Cox, Andrew Cohen

a long time ago in a galaxy far, far away, Albert Einstein, Albert Michelson, Apollo 11, Arthur Eddington, California gold rush, Cepheid variable, cosmic microwave background, dark matter, Dmitri Mendeleev, Eddington experiment, Eyjafjallajökull, Ford Model T, heat death of the universe, Higgs boson, Isaac Newton, James Watt: steam engine, Johannes Kepler, Karl Jansky, Large Hadron Collider, Magellanic Cloud, Mars Rover, Neil Armstrong, Stephen Hawking, the scientific method, time dilation, trade route

Although each dish works independently, they can be combined together to create a single antenna with an effective diameter of over 36 kilometres (22 miles). This allows this vast virtual telescope to achieve very high-resolution images of the sky at radio wavelengths. Radio astronomy has a history dating back to the 1930s, when the astronomer Karl Jansky discovered that the Universe could be explored not just through the visible part of the electromagnetic spectrum, but also through the detection of radio waves. Over a period of several months, Jansky used an antenna that looked more like a Meccano set than the VLA to record the radio waves from the sky.


pages: 253 words: 80,074

The Man Who Invented the Computer by Jane Smiley

1919 Motor Transport Corps convoy, Alan Turing: On Computable Numbers, with an Application to the Entscheidungsproblem, Albert Einstein, anti-communist, Arthur Eddington, Bletchley Park, British Empire, c2.com, Charles Babbage, computer age, Computing Machinery and Intelligence, Fellow of the Royal Society, Ford Model T, Henri Poincaré, IBM and the Holocaust, Isaac Newton, John von Neumann, Karl Jansky, machine translation, Norbert Wiener, Norman Macrae, Pierre-Simon Laplace, punch-card reader, RAND corporation, Turing machine, Vannevar Bush, Von Neumann architecture

In 1930, at the same time Atanasoff was working on his dissertation at the University of Wisconsin, Stibitz was working on his at Cornell University. Stibitz’s dissertation, like Atanasoff’s, involved extensive and tedious calculations. But Stibitz went to work for Bell Labs in New York City. Bell Labs, a joint enterprise belonging to Western Electric and AT&T, was in both the discovery business and the invention business. In 1932, Karl Jansky had detected radio noise that originated at the center of the Milky Way; in 1933, Bell Labs scientists had managed to transmit stereophonic sound over telephone wires (a symphony recorded in Philadelphia was transmitted to Washington, D.C.). Stibitz, whose doctorate was in applied mathematics, was surrounded by equipment as well as engineers.


pages: 745 words: 207,187

Accessory to War: The Unspoken Alliance Between Astrophysics and the Military by Neil Degrasse Tyson, Avis Lang

active measures, Admiral Zheng, airport security, anti-communist, Apollo 11, Arthur Eddington, Benoit Mandelbrot, Berlin Wall, British Empire, Buckminster Fuller, Carrington event, Charles Lindbergh, collapse of Lehman Brothers, Colonization of Mars, commoditize, corporate governance, cosmic microwave background, credit crunch, cuban missile crisis, dark matter, Dava Sobel, disinformation, Donald Trump, Doomsday Clock, Dr. Strangelove, dual-use technology, Eddington experiment, Edward Snowden, energy security, Eratosthenes, European colonialism, fake news, Fellow of the Royal Society, Ford Model T, global value chain, Google Earth, GPS: selective availability, Great Leap Forward, Herman Kahn, Higgs boson, invention of movable type, invention of the printing press, invention of the telescope, Isaac Newton, James Webb Space Telescope, Johannes Kepler, John Harrison: Longitude, Karl Jansky, Kuiper Belt, Large Hadron Collider, Late Heavy Bombardment, Laura Poitras, Lewis Mumford, lone genius, low earth orbit, mandelbrot fractal, Maui Hawaii, Mercator projection, Mikhail Gorbachev, military-industrial complex, mutually assured destruction, Neil Armstrong, New Journalism, Northpointe / Correctional Offender Management Profiling for Alternative Sanctions, operation paperclip, pattern recognition, Pierre-Simon Laplace, precision agriculture, prediction markets, profit motive, Project Plowshare, purchasing power parity, quantum entanglement, RAND corporation, Ronald Reagan, Search for Extraterrestrial Intelligence, skunkworks, South China Sea, space junk, Stephen Hawking, Strategic Defense Initiative, subprime mortgage crisis, the long tail, time dilation, trade route, War on Poverty, wikimedia commons, zero-sum game

One big problem with long-distance service, aside from the price tag, was, as AT&T itself describes the situation, “Telephone service via available radio technology was far from ideal: it was subject to fading and interference, and had strictly limited capacity.”18 Another, double-edged problem was that few channels were available in the low-frequency, long-wavelength part of the radio spectrum, while the higher-frequency, short-wavelength part of it—the part that could carry much more information—was still unfamiliar territory, scientifically and technologically. Not until it was mastered could there be live FM stereo broadcasts from the Metropolitan Opera, which began in the 1970s. But let’s not get ahead of ourselves. In 1928 AT&T’s three-year-old R & D facility, Bell Telephone Laboratories, hired a young physicist named Karl Jansky to study Earth-based radio sources that might account for all the hissing and fading—the noise, the static—in terrestrial radio communications. After constructing a novel rotating antenna, tuned to capture a radio wavelength of 14.6 meters (frequency: 20.5 MHz), Jansky spent several years waiting for signals to drift by his receiver, studying the signal patterns, and scrupulously interpreting the results.

., also a radio engineer, called his brother Karl’s work on noise “in effect a wedding ceremony” between pure science and applied science, pointing out that he himself (and by implication, most people working in S & T) “used to define a pure scientist as one who if he saw a practical application of what he was doing somehow felt contaminated by commercialism and an applied scientist as one who if he could not see a practical application of his work would lose interest.” C. M. Jansky Jr., “My Brother Karl Jansky and His Discovery of Radio Waves from Beyond the Earth,” Cosmic Search 1:4, www.bigear.org/vol1no4/jansky.htm (accessed Nov. 3, 2015). 21.Grote Reber, “A Play Entitled the Beginning of Radio Astronomy,” J. Royal Astronomical Society of Canada 82:3 (June 1988), 94, adsabs.harvard.edu/full/1988JRASC..82...93R (accessed Apr. 19, 2017). 22.For Jansky’s own detailed description of this apparatus, see Jansky, “Directional Studies,” 4–7. 23.Lisa Grossman, “New Questions about Arecibo’s Future Swirl in the Wake of Hurricane Maria,” ScienceNews, Sept. 29, 2017, www.sciencenews.org/blog/science-public/new-questions-about-arecibos-future-swirl-wake-hurricane-maria (accessed Oct. 28, 2017). 24.Cheng Yingqi and Yang Jun, “Massive Telescope’s 30-ton ‘Retina’ Undergoes Final Test,” China Daily, Nov. 23, 2015, www.chinadaily.com.cn/china/2015-11/23/content_22509826.htm (accessed Apr. 19, 2017). 25.Initially the British called their version RDF, or radio direction finding.


pages: 550 words: 154,725

The Idea Factory: Bell Labs and the Great Age of American Innovation by Jon Gertner

Albert Einstein, back-to-the-land, Black Swan, business climate, Charles Babbage, Claude Shannon: information theory, Clayton Christensen, complexity theory, corporate governance, cuban missile crisis, Dennis Ritchie, Edward Thorp, Fairchild Semiconductor, Henry Singleton, horn antenna, Hush-A-Phone, information retrieval, invention of the telephone, James Watt: steam engine, Karl Jansky, Ken Thompson, knowledge economy, Leonard Kleinrock, machine readable, Metcalfe’s law, Nicholas Carr, Norbert Wiener, Picturephone, Richard Feynman, Robert Metcalfe, Russell Ohl, Sand Hill Road, Silicon Valley, Skype, space junk, Steve Jobs, Telecommunications Act of 1996, Teledyne, traveling salesman, undersea cable, uranium enrichment, vertical integration, William Shockley: the traitorous eight

A discovery often describes a scientific observation of the natural world—the first observation of Jupiter’s moons, for example, or the isolation of a bacteria that causes a deadly plague. Also, a discovery could represent a huge scientific achievement but an economic dead end. In the early 1930s, for instance, at the Bell Labs radio facility in Holmdel, New Jersey, a young engineer named Karl Jansky created a movable antenna to research atmospheric noise. With this antenna, he observed a steady hiss emanating from the Milky Way. In this moment, Jansky had essentially started the field of radio astronomy—a discovery that paid a lasting dividend to his and Bell Labs’ renown. On the other hand, it never led to any kind of profitable telecommunications invention or device.28 John Bardeen, the most careful of men, referred to his transistor work as a “discovery” of “transistor action”; he and Brattain had effectively observed in their experiment how a current applied to a slightly impure slice of germanium could hasten the movement of microscopic holes inside and thus amplify a signal.


pages: 661 words: 169,298

Coming of Age in the Milky Way by Timothy Ferris

Albert Einstein, Albert Michelson, Alfred Russel Wallace, anthropic principle, Arthur Eddington, Atahualpa, Cepheid variable, classic study, Commentariolus, cosmic abundance, cosmic microwave background, cosmological constant, cosmological principle, dark matter, delayed gratification, Eddington experiment, Edmond Halley, Eratosthenes, Ernest Rutherford, Garrett Hardin, Gary Taubes, Gregor Mendel, Harlow Shapley and Heber Curtis, Harvard Computers: women astronomers, Henri Poincaré, invention of writing, Isaac Newton, Johannes Kepler, John Harrison: Longitude, Karl Jansky, Lao Tzu, Louis Pasteur, Magellanic Cloud, mandelbrot fractal, Menlo Park, Murray Gell-Mann, music of the spheres, planetary scale, retrograde motion, Richard Feynman, Search for Extraterrestrial Intelligence, Searching for Interstellar Communications, source of truth, Stephen Hawking, Thales of Miletus, Thomas Kuhn: the structure of scientific revolutions, Thomas Malthus, time dilation, Wilhelm Olbers

Noteworthy Events: Kurt Gödel’s second incompleteness theorem indicates that the consistency of any system, including scientific systems, cannot be proved internally—i.e., that mathematics, and science are inherently open-ended. Time: 1932 Noteworthy Events: James Chadwick discovers the neutron. Noteworthy Events: Carl Anderson, without knowing of Dirac’s 1931 paper postulating its existence, discovers the positron. Noteworthy Events: Karl Jansky finds that the Milky Way emits radio waves, opening door on the science of radio astronomy. Time: 1935 Noteworthy Events: Hideki Yukawa predicts existence of the meson. Time: 1939 Noteworthy Events: Niels Bohr and John Archibald Wheeler develop the theory of nuclear fission. Noteworthy Events: Hans Bethe and Carl Friedrich von Weizsäcker independently arrive at theory of the carbon and proton-proton reactions in stars.