Grote Reber

American radio astronomer (1911–)

Reber, who was born in Wheaton, Illinois, studied at the Illinois Institute of Technology and became a radio engineer. His work in radio astronomy has taken him to many places including Washington DC in the late 1940s where he was chief of the Experimental Microwave Research Section, Hawaii, in 1951, and Tasmania in 1954 where he joined the Commonwealth Scientific and Industrial Research Organization. From 1957 to 1961 he worked at the National Radio Astronomy Observatory in Virginia and then returned to Tasmania to complete the studies he had started there.

Reber built the first antenna to be used specifically for extraterrestrial radio observations and was largely responsible for the early developments in radio astronomy. For many years he was probably the world's only radio astronomer. His interest was aroused in 1933 by the work of Karl Jansky. In 1937 he built, in his own backyard, a 30-foot (9.4-m) steerable parabolic bowl-shaped radio reflector with an antenna at its focus. Working at a shorter wavelength than Jansky, 60 centimeters instead of 15 meters, he began to spot emission peaks in the Milky Way. These were the intense radio sources in the constellations Cygnus, Taurus, and Cassiopeia. He published his results from 1940 onward and these came to the attention of many astronomers who, although unable to follow him immediately owing to the war, recognized the value of his work. Over the years Reber has constructed several telescopes so that he could map the radio sky at different wavelengths. His Hawaiian instrument operated at 5.5–14 meters while in Tasmania he used radio waves of 144 meters.

It was reading Reber's results that stimulated Jan Oort to pose the problem that led to Hendrik van de Hulst's discovery of the 21-centimeter hydrogen emission.

Grote Reber (born 1911) was a radio engineer who became interested in radio astronomy as a hobby. He built the first radio telescope in the backyard of his home and, for a decade, he was the only radio astronomer in the United States. Reber recorded radio signals at different wavelengths and created the first radio map of the universe.

Grote Reber was born on December 22, 1911 in Wheaton, Illinois, about 25 miles west of Chicago. His mother, Harriet Grote, was a grade school teacher who interested Reber in astronomy with a book by one of her former students, Edwin P. Hubble. As a child, Reber was interested in radio as a hobby. By the time he was 15 years old he had built his first transmitter receiver and could communicate with other "ham" radio amateurs around the world.

In 1933 Reber graduated from the Illinois Institute of Technology with a Bachelor of Science degree in electrical engineering. After graduation he went to work for a Chicago radio manufacturer, the Stewart Warner Company, where he designed radio receivers. During the same year, Karl Jansky published his first report describing how he had detected the first radio waves from outer space. Reber read Jansky's report and was inspired to pursue these signals himself.

Karl Guthe Jansky was a physicist at Bell Telephone Laboratories in Holmdel, New Jersey. In 1927 Bell had created the first transatlantic radiotelephone. However, the telephone links were highly susceptible to electrical interference. In 1930 Jansky was asked to locate the source of the interference. Within two years Jansky discovered three sources of the problem, two of which were related to storms and the third came from an unknown origin. Jansky pursued this third source and discovered that it appeared four minutes earlier each day, which corresponded to the 23 hour 56 minute period of the stars. This meant that the stars emitted energy in the form of radio waves, as well as light waves. Jansky followed up this work with another report in 1935 which linked the radio waves to the distribution of the Milky Way.

Jansky was then assigned to work on other projects at Bell Laboratories and never had the opportunity to continue his work on stellar radio waves. However, Reber read Jansky's work in the Proceedings of the Institute of Radio Engineers journal and was determined to continue his work. He first needed to build a telescope capable of detecting cosmic radio waves. In the midst of the Great Depression, Reber was unable to garner academic or financial support for his project. Astronomers were not familiar with radio technology and were still absorbed with visual inspections of the universe. Reber was not discouraged by this lack of enthusiasm and was determined to work on the project alone.

Built First Radio Telescope

Reber drew up plans to build a large parabolic reflector to collect radio waves and feed them into a radio receiver. He presented his plans to the American Bridge Company, which quoted him a price of $7,000 to build the telescope. Since this price was not affordable to Reber, he decided to construct the device himself. With the help of two friends, Reber built a reflector out of galvanized sheet metal and wooden rafters. The mirror was 31 feet in diameter with a focal length of 20 feet. With no external financial support, Reber spent $1,300 of his own money to build the first radio telescope in the backyard of his home in Wheaton. This was $300 more than the price of a new automobile. The telescope took four months in 1937 to build, but stood in Reber's yard for ten years.

Once the telescope was in place Reber went to work trying to confirm Jansky's findings. He worked at Stewart Warner during the day and recorded signals in his backyard at night when there was less interference from cars. Reber originally chose to operate the telescope at a wavelength of nine centimeters. However, after a year, he failed to detect anything with his telescope. In 1938 he made several improvements to his telescope using parts from his employer and from the University of Chicago and he decided to increase the wavelength to 33 centimeters. Reber was still unsuccessful. A year later he increased the wavelength to 1.87 meters. After two years of trying to detect cosmic radio waves, Reber was finally successful at this longer wavelength.

Major Discoveries

Once Reber had an operational telescope he set out to make a radio map of the Milky Way. First he confirmed Jansky's claim that the static was strongest at the constellation Sagittarius, the center of the universe. He also detected strong signals from other constellations, namely Cygnus, Cassiopeia, Canis Major, and Puppis. Reber published his initial findings in the Proceedings of the Institute of Radio Engineers. He also tried once again to get astronomers interested in radio waves. Reber submitted his paper to the Astrophysical Journal, but there was no one qualified to review the paper. As Reber explained in a January 1988 article in The Toronto Star, "The astronomers couldn't understand the radio engineering and the radio engineers couldn't understand the astronomy." The editor of the journal decided to publish the paper without a review and it finally appeared in June of 1940.

Reber continued to improve his telescope and map the universe. In 1943 he started to explore the Sun and found strong radio signals. This discovery had already been made accidentally by the British a year earlier but had remained a military secret until after World War II. Reber completed the first radio map of the galaxy in 1944 based on over 200 chart recordings. He also noted that radio waves could penetrate the interstellar dust that blocks the view of the Milky Way. This was an important improvement over visual inspections of the universe.

For nearly a decade Reber worked alone in his backyard as America's only radio astronomer. However, once Reber's findings were circulated among astronomers and once World War II was over, interest in the field began to grow. Reber stopped his operations in Wheaton in 1947 and moved his telescope to the United States Bureau of Standards. In 1948 Reber went to work at the University of Virginia as the chief of the experimental microwave radio section. In 1951 he moved to Hawaii to work in an area that had less man-made radio interference. He used a telescope that worked at 5.5 to 14 meters to try to find new sources of radio waves. He left his original telescope behind and it was moved in 1960 to the National Radio Astronomy Observatory in Green Bank, West Virginia, where it is still on public display.

Moved to Tasmania

In 1954 Reber moved to Tasmania, off the coast of southern Australia, to be closer to the south magnetic pole where the Earth's ionosphere was the weakest and, therefore, radio waves were the strongest. He joined the Commonwealth Scientific and Industrial Research Organization and constructed a new wire-antenna instrument over 3,000 feet in diameter that measured wavelengths at 150 meters. It is one of the world's largest radio telescopes. Aside from a brief period between 1957 and 1960 when Reber worked for the National Radio Astronomy Observatory, he spent the rest of his life in Tasmania. One of his first projects there was to map the southern radio sky. He found that the southern map was the inverse of what he had mapped in Illinois at much shorter wavelengths.

Even in Tasmania Reber's work was still hindered by the ionosphere. While the ionosphere protects the Earth from long-wave radiation from space, it also prevents certain radio frequencies from escaping. In 1985 Reber used a mission of the space shuttle Challenger to his advantage. Exhaust gases from the space shuttle's engines temporarily neutralized the electrical particles in the ionosphere. Therefore, on August 4, 1985 when Challenger was over Reber's telescope in Hobart, Australia, the shuttle released a quarter ton of fuel to create a hole in the ionosphere for a few hours. Through this hole Reber was able to find cosmic radiation at a wavelength of 176 meters, which was the first time radio waves of this length from space had ever been recorded.

Reber's next project took him to the other end of the Earth. He took advantage of a solar minimum of 1986 and 1987 to try to map the northern sky at 144 meters to match his southern sky map at that same wavelength. He spent two winters as a visiting scientist at the National Research Council of Canada working with an antenna at Ashton, southwest of Ottawa. However, the antenna was a part of some obsolete defense equipment and was badly damaged, so Reber was unable to complete his map.

Challenged Big Bang Theory

Reber continued to work into the next decade, when he was in his eighties. He was trying to find more ways to create holes in the ionosphere so that he could get more data from longer wavelengths. Reber believed that these data were key to disproving the Big Bang theory of how the universe evolved. His radio maps of space have shown that the radio sky is brighter at longer wavelengths than shorter wavelengths. Reber believes that this is due to photons losing energy as they travel through space, while proponents of the Big Bang theory see this as a sign of a receding galaxy. Reber has given many lectures on why he does not believe in the Big Bang theory and many astronomers disagree with him. Reber, however, is accustomed to being alone in his beliefs and is waiting for an opportunity to test them.

What started out as a one-man project in Reber's backyard in Wheaton, Illinois has evolved into the serious science of radio astronomy. For the first decade Reber had been the only radio astronomer. Now the discipline has gained support in the United States, Britain, Australia, and elsewhere. This technology has led to important discoveries in astronomy, especially with respect to quasars and pulsars. It has even become popular among the public. For example, there is now a Society of Radio Astronomers which is an international organization designed to help hundreds of radio astronomy amateurs observe the radio sky. Reber's conviction in his beliefs and his life-long dedication to his profession have increased our knowledge of the universe and have even challenged our beliefs about its conception.

Books

Classics in Radio Astronomy, edited by Woodruff Turner Sullivan III, D. Reidel Publishing Company, 1982.

Hey, J.S., The Evolution of Radio Astronomy, Science History Publications, 1973.

Kraus, John, Big Ear, Cygnus-Quasar Books, 1976.

Kraus, John, Big Ear Two: Listening for Other-Worlds, Cygnus-Quasar Books, 1995.

Kraus, John, Radio Astronomy, Cygnus-Quasar Books, 1986.

Malphrus, Benjamin K., The History of Radio Astronomy and the National Radio Astronomy Observatory: Evolution Toward Big Science, Krieger Publishing Company, 1996.

Tucker, Wallace, and Karen Tucker, The Cosmic Inquirers, Harvard University Press, 1986.

Verschuur, Gerrit L., The Invisible Universe Revealed: The Story of Radio Astronomy, Springer-Verlag, 1987.

Periodicals

Astronomy, June 1992, p. 46.

New Scientist, October 29, 1994, p. 53.

New York Times, November 17, 1981, p. C1.

Sky and Telescope, July 1988, p. 28; July 1988, p. 31; November 1988, p. 492.

Toronto Star, January 23, 1988, p. M3; January 30, 1988, p. M3.

Online

"Grote Reber and His Radio Telescope," http://info.gb.nrao.edu/~fghigo/fgdocs/reber/reber.html (January 17, 2001).

Grote Reber
Grote Reber
Born	December 22, 1911(1911-12-22) Wheaton, Illinois
Died	December 20, 2002 (aged 90) Tasmania
Nationality	United States
Fields	radio astronomy

Grote Reber (December 22, 1911—December 20, 2002), was an amateur astronomer and pioneer of radio astronomy. He was instrumental in investigating and extending Karl Jansky's pioneering work, and conducted the first sky survey in the radio frequencies.

Contents 1 Life 2 Honorary awards 3 Named after him 4 References 5 External links 6 See also

Life

Reber was born and raised in Wheaton, Illinois, a suburb of Chicago, and graduated from Armour Institute of Technology (later Illinois Institute of Technology) in 1933 with a degree in radio engineering. He was an amateur radio operator (ex-W9GFZ), and worked for various radio manufacturers in Chicago from 1933 to 1947. When he learned of Karl Jansky's work in 1933,^[1][2][3] he decided this was the field he wanted to work in, and applied to Bell Labs, where Jansky was working. However this was during the height of the Great Depression and there were no jobs available.

Instead, Reber decided to build his own radio telescope in his back yard in Wheaton. His design was considerably more advanced than Jansky's, consisting of a parabolic sheet metal mirror 9 meters in diameter, focusing to a radio receiver 8 meters above the mirror. The entire assembly was mounted on a tilting stand, allowing it to be pointed in various directions, though not turned. The telescope was completed in September 1937.^[4][5]

First^* Radio Telescope - Wheaton, IL 1937

Replica of Reber Radio Telescope at National Radio Astronomy Observatory in Green Bank, WV

Reber's first receiver operated at 3300 MHz and failed to detect signals from outer space, as did his second, operating at 900 MHz. Finally, his third attempt, at 160 MHz, was successful in 1938, confirming Jansky's discovery. In 1940 he won his first professional publication,^[4] in the Astrophysical Journal, but Reber refused a research appointment from Yerkes.^[6] He turned his attention to making a radiofrequency sky map, which he completed in 1941 and extended in 1943. He published a considerable body of work during this era, and was the initiator of the "explosion" of radio astronomy in the immediate post-Second World War era.

During this time he uncovered a mystery that was not explained until the 1950s. The standard theory of radio emissions from space was that they were due to black-body radiation, light (of which radio is a non-visible form) that is given off by all hot bodies. Using this theory one would expect that there would be considerably more high-energy light than low-energy, due to the presence of stars and other hot bodies. However Reber demonstrated that the reverse was true, and that there was a considerable amount of low-energy radio signal. It was not until the 1950s that synchrotron radiation was offered as an explanation for these measurements.

Reber sold his telescope to the National Bureau of Standards, and it was erected on a turntable at their field station in Sterling, Virginia. Eventually the telescope made its way to NRAO in Green Bank, West Virginia,^{Sullivan 1984} and Reber supervised its reconstruction at that site. Reber helped with a reconstruction of Jansky's original telescope as well.

Starting in 1951, he received generous support from the Research Corporation in New York, and moved to Hawaii.^[7] In the 1950s he wanted to return to active studies but much of the field was already filled with very large and expensive instruments. Instead he turned to a field that was being largely ignored, that of medium frequency (hectometre) radio signals in the 0.5—3 MHz range, around the AM broadcast bands. However, signals with frequencies below 30 MHz are reflected by an ionized layer in the Earth's atmosphere called the ionosphere. In 1954, Reber moved to Tasmania,^[7] a triangular island off the southern coast of Australia, where he worked with Bill Ellis at the University of Tasmania.^[8] There, on very cold, long, winter nights the ionosphere would, after many hours shielded from the sun's radiation by the bulk of the Earth, 'quieten' and de-ionize, allowing the longer radio waves into his antenna array. Tasmania also offered low levels of man-made radio noise, which permitted reception of the faint signals from outer space.

In the 1960s he had an array of dipoles set up on the Sheep Grazing property of Dennistoun, about 5 km north of the town of Bothwell, where he lived in a house of his own construction he decided to build after he purchased a job lot of coach bolts at a local auction. He imported Oregon pine direct from a sawmill in Oregon, huge beams, "8x4", and high tech double glazed window panes, also from the U.S. He bolted the house, of his own design, together with the bolts. The window panes formed a north facing passive solar wall, heating mat black painted, dimpled copper sheets, from which the warmed air rose by convection. The house was so well thermally insulated that the oven in the kitchen was nearly unusable because the heat from it, unable to escape, would raise the temperature of the room to over 50 °C (120 °F).

His house was never completely finished. It was meant to have a passive heat storage device, basically a thermally insulated pit full of dolerite rocks, underneath, but although his mind was sharp, his body started to fail him in his later years, and he was never able to move the rocks. He was fascinated by mirrors and had at least one in every room. One of the ironies of Grote Reber's life is that he lived twice as long as Karl Jansky.

He had one of the amplifiers from the prime focus of his first telescope. Probably the one used at 900 MHz, it was of compact point-to-point construction and used two R.C.A. type 955 'acorn' thermionic valves. All the rubber-insulated wires in it had perished and the rubber was hard and crumbly. He powered this amplifier, and all his later receivers at Dennistoun, from batteries, to avoid interference entering the equipment along power cables.

Reber was not a believer of the "big bang" theory; he believed that red shift was due to repeated absorption and re-emission or interaction of light and other electromagnetic radiations by low density dark matter, over intergalactic distances, and he published an article called "Endless, Boundless, Stable Universe", which outlined his theory.

His memorial plaque at the Mullard Radio Astronomy Observatory

He was looked after in his final days at the Ouse District Hospital 30 km northeast of Hobart, Tasmania, where he died in 2002, two days before his 91st birthday. His ashes are located at Bothwell Cemetery in Tasmania and at many major radio observatories around the world:

• Mount Pleasant Radio Observatory and Grote Reber Museum, Cambridge, Tasmania, Australia
• Parkes Observatory, New South Wales, Australia
• Molonglo Observatory, Bungendore, New South Wales, Australia
• Dwingeloo Radio Observatory, Netherlands
• Jodrell Bank, Cheshire, England
• Mullard Radio Astronomy Observatory, Cambridgeshire, England
• Dominion Astrophysical Observatory, British Columbia, Canada
• N.A.S.A. Goldstone Apple Valley Radio Telescope, California
• United States Naval Observatory, D.C.
• National Radio Astronomy Observatory, Greenbank, West Virginia
• Arecibo Observatory, Puerto Rico
• University of Illinois Radio Telescope, Vermillion County, Illinois
• University of California at Davis
• University of Hawaii, on the summit of Haleakala
• Giant Metrewave Radio Telescope, India
• Tuorla Observatory, Turku, Finland
• Pushchino Radio Astronomy Observatory, Russia

Honorary awards

• Honorary Doctor of Science degree from Ohio State University (1962)^[4]
• Bruce Medal of the Astronomical Society of the Pacific (1962)
• Henry Norris Russell Lectureship (1962)
• Elliott Cresson Medal of the Franklin Institute (physics, 1963)
• Jackson-Gwilt Medal of the Royal Astronomical Society (1983)

Named after him

• Asteroid 6886 Grote
• The Grote Reber Medal^[9]
• Museum at the Mount Pleasant Radio Observatory, Cambridge, Tasmania, opened 20 January 2008^[10]

References

* Sullivan, W.T. (1984). The Early Years of Radio Astronomy. Cambridge University Press. ISBN 0-521-25485-X pg 48

1. ^ [1] NYTimes for-pay article
2. ^ [2] John David North, Cosmos: an illustrated history of astronomy and cosmology. University of Chicago Press, 2008, p.661. ISBN 0226594416
3. ^ [3] Kip S. Thorne, Black holes and time warps: Einstein's outrageous legacy. W. W. Norton & Company, 1994, p. 324. ISBN 0393312763
4. ^ ^{a b c} [4] NRAO bio, photos
5. ^ NRAO timeline
6. ^ Thorne, p.327.
7. ^ ^{a b} Smithsonian/NASA bio
8. ^ utas.edu.au Companion to Tasmanian History: Astronomy
9. ^ Queen Victoria Museum and Art Gallery
10. ^ Museum marks life of first radio astronomer, Australian Broadcasting Corporation, 18 January 2008 (accessed 24 January 2008)

• The Early Years of Radio Astronomy, W.T. Sullivan III ed. pg 48
• [5] Peter L. Manly, Unusual Telescopes. Cambridge University Press, 1995, p. 77. ISBN 052148393X
• [6] Joseph L. Spadley, The First True Radio Telescope. Sky and Telescope vol.76:no. 1(1988) pages 3, 28-30
• [7] Paul A. Feldman, Grote Reber: Yesterday and Today. Sky and Telescope vol.76:no. 1(1988) page 31
• [8] Chicago Sunday Times, What is It?. May 7, 1939. - Article about Wheaton, Illinois; mentions Peter Reber's "atmospheric static finder"
• [9] Kraus, J. D., Grote Reber - Founder of Radio Astronomy. R.A.S. Canada. Journal V. 82, No. 3/Jun, P.107, 1988

External links

• Bulletin of the American Astronomical Society obituary
• Guardian obituary
• Engineer whose invention of the radio telescope - built in his back garden - transformed postwar astronomy
• Grote Reber, ex-W9GFZ
• The Grote Reber Museum

See also

• Reber Radio Telescope
• John D. Kraus
• Astronomical radio source
• Radiophysics

v • d • e Radio astronomy Main articles Astronomical interferometer / History · Very Long Baseline Interferometry · Radio telescope · Radio window · Astronomical radio source Notable radio telescopes List of radio telescopes Single dish Arecibo Observatory (Puerto Rico) · Effelsberg Telescope (Germany) · Green Bank Telescope (West Virginia, USA)  · Lovell Telescope (UK) · Parkes Observatory (Australia) Interferometers Combined Array for Research in Millimeter-wave Astronomy (Cedar Flat, CA)  · European VLBI Network (Europe) · Giant Metrewave Radio Telescope (India) · MERLIN (UK) · Molonglo Observatory Synthesis Telescope (Canberra, Australia) · One-Mile Telescope (UK) · Very Large Array (New Mexico, USA) · Very Long Baseline Array (USA) · Westerbork Synthesis Radio Telescope (Netherlands) Proposed/in-progress telescopes Five hundred meter Aperture Spherical Telescope (China) · Allen Telescope Array (California, USA) · Atacama Large Millimeter Array (Chile) · LOFAR (Netherlands) · Murchison Widefield Array (Australia) · PaST (China) · Square Kilometre Array (TBD) Observatories Algonquin Radio Observatory (CAN) · Haystack Observatory (US) · Jodrell Bank Observatory (UK) · Mullard Radio Astronomy Observatory (UK) · National Radio Astronomy Observatory (USA) · Special Astrophysical Observatory of the Russian Academy of Science (Russia) People Arthur Covington · Antony Hewish · Karl Guthe Jansky · Bernard Lovell · Jan Oort · Groete Reber · Martin Ryle Related articles Cosmic microwave background radiation · SETI · Interferometry · Radio propagation · Aperture synthesis · Wow! signal Other types of astronomical observation: Optical astronomy · Submillimetre astronomy · Infrared astronomy · High-energy astronomy See also: Radio telescope category list

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