Reber
Reber, Grote
ACHIEVEMENTS:
Radio telescope
DATE AND PLACE OF BIRTH:
22 December 1911, Wheaton, IL
DATE AND PLACE OF DEATH AND AGE AT DEATH:
DISCIPLINE: Radio engineer and astronomer
FIELD: Radio astronomy
EDUCATION: Illinois Institute of Technology
MAJOR WORK:
LIFE AND TIMES:
Reber was virtually the only person who reacted to Jansky's* discovery of extraterrestial radio waves in 1932.
Reber was an enthusiastic amateur radio buff and tried to adapt his own shortwave radio to pick up interstellar radio waves. He did not succeed in doing this, but he was so keen to find out about cosmic radiation that he built a huge paraboloid bowl in the garden of his house in Wheaton, IL. It was 31 feet across and could be steered to face different parts of the sky. Reber had made the first radio telescope.
It remained the only one until after World War II and provided the model for the large paraboloid radio telescope at Jodrell Bank*, England, which was involved with many of the early US spaceflights.
Reber was able to confirm Jansky's results and then made the observations from which he produced the first radio maps of the sky. He had concentrated on much shorter wave signals than Jansky and this, together with his bigger aerial, gave him more directionality. He found that radio signals were stronger when coming from the direction of the Milky Way (where there were most stars) and weakest from the parts of the sky with few stars. He also found that the contours of the radio emission followed the pattern of the distribution of the ordinary stars in the Milky Way but he failed to relate strong signals to any particular celestial object.
These findings led Reber to suggest that radio waves were generated in the hydrogen gas in the spaces between stars. He tried to detect radio waves from the sun but failed because he was observing at a period of minimum solar activity. Reber's confirmation of Jansky's findings laid the foundation for the future work in radio astronomy by Penzias* & Wilson* resulting in their discovery of cosmic radiation in 1965.
Reber moved his radio telescope to Sterling, VA. after the war and was appointed chief of the Experimental Microwave Research section in Washington, D.C. In 1951 he built a new telescope in Hawaii, where he mapped the celestial source of low-frequency long wave signals. In 1954 he joined the Commonwealth Scientific and Industrial Research organization in Tasmania, Australia, one of the few places in the world where the atmosphere is sometimes transparent to electromagnetic radiation more than 30 metres long. Australian scientists had already made discoveries which cast doubt on Reber's earlier suggestion that radio waves were generated in interstellar hydrogen gas.
In 1957 Reber accepted a position at the National Radio Astronomy Observatory at Green Park, Va., where a new and bigger radio telescope had been built. However, he returned to Tasmania in 1961 where he helped to complete the mapping of radio wave sources over 270 metres.
ASSESSMENT: Reber built the world's first radio telescope and his findings helped to lay the foundation for the development of radio astronomy.
EXTRA CONNECTIONS: None
ONELINER: Grote Reber, founder of radio astronomy
BIBLIOGRAPHY:
Bernstein, Jeremy, Three Degrees Below Zero, Cambridge University Press, Cambridge, 1984
Lovell, Bernard,Voice of the Universe, Praeger, London, 1987