William Frederick Denning (25 November 1848 – 9 June 1931) was a British

amateur An amateur () is generally considered a person who pursues an avocation independent from their source of income. Amateurs and their pursuits are also described as popular, informal, self-taught, user-generated, DIY, and hobbyist. History ...

astronomer An astronomer is a scientist in the field of astronomy who focuses their studies on a specific question or field outside the scope of Earth. They observe astronomical objects such as stars, planets, moons, comets and galaxies – in either ...

who achieved considerable success without formal scientific training. He is known for his catalogues of meteor radiants, observations of Jupiter's red spot, and for the discovery of five

comet A comet is an icy, small Solar System body that, when passing close to the Sun, warms and begins to release gases, a process that is called outgassing. This produces a visible atmosphere or coma, and sometimes also a tail. These phenomena ...

s. Outside astronomy, as a young man, Denning showed prowess at

cricket Cricket is a bat-and-ball game played between two teams of eleven players on a field at the centre of which is a pitch with a wicket at each end, each comprising two bails balanced on three stumps. The batting side scores runs by st ...

to the extent W G Grace invited him to play for

Gloucestershire Gloucestershire ( abbreviated Glos) is a county in South West England. The county comprises part of the Cotswold Hills, part of the flat fertile valley of the River Severn and the entire Forest of Dean. The county town is the city of ...

. However Denning’s retiring nature made him decline the offer.

Career

Denning devoted a great deal of time to searching for comets, and discovered five of them, including the

periodic comet Periodic comets (also known as short-period comets) are comets with orbital periods of less than 200 years or that have been observed during more than a single perihelion passage (e.g. 153P/Ikeya–Zhang). "Periodic comet" is also sometimes us ...

72P/Denning–Fujikawa and the

lost comet A lost comet is one which was not detected during its most recent perihelion passage. This generally happens when data is insufficient to reliably calculate the comet's location or if the solar elongation is unfavorable near perihelion passage. ...

D/1894 F1. The latter was the last comet discovered on British soil until the discoveries of

George Alcock George Eric Deacon Alcock, MBE (28 August 1912, in Peterborough, Northamptonshire – 15 December 2000) was an English astronomer. He was one of the most successful visual discoverers of novae and comets. George’s interest in astronomy was ...

. Denning also studied

meteor A meteoroid () is a small rocky or metallic body in outer space. Meteoroids are defined as objects significantly smaller than asteroids, ranging in size from grains to objects up to a meter wide. Objects smaller than this are classified as mi ...

s and

nova A nova (plural novae or novas) is a transient astronomical event that causes the sudden appearance of a bright, apparently "new" star (hence the name "nova", which is Latin for "new") that slowly fades over weeks or months. Causes of the dramat ...

e, discovering

Nova Cygni 1920 V476 Cygni or Nova Cygni 1920 was a nova which occurred in the constellation Cygnus in 1920. It was discovered by William Frederick Denning, an English amateur astronomer, at 09:30 GMT on 20 August 1920, at which time it had a magnitude ...

(V476 Cyg). From 1869 Denning held the combined post of secretary and treasurer of the short-lived Observing Astronomical Society. Denning was elected to the

Royal Astronomical Society (Whatever shines should be observed) , predecessor = , successor = , formation = , founder = , extinction = , merger = , merged = , type = NG ...

on 8 June 1877. He was also elected to the British Astronomical Association on 26 October 1898. Subsequently directed its Comet (1891–1893) and Meteor (1899–1900) Sections. He won the ''Prix Valz'' of the

French Academy of Sciences The French Academy of Sciences (French: ''Académie des sciences'') is a learned society, founded in 1666 by Louis XIV at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French scientific research. It was at ...

for 1895. During his life, Denning published 1179 articles in prominent scientific journals including ''

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 ...

'', '' The Observatory'', ''

Astronomische Nachrichten ''Astronomische Nachrichten'' (''Astronomical Notes''), one of the first international journals in the field of astronomy, was established in 1821 by the German astronomer Heinrich Christian Schumacher. It claims to be the oldest astronomical journ ...

'', '' Journal of the Royal Astronomical Society of Canada'', ''

Journal des Observateurs ''Astronomy & Astrophysics'' is a monthly peer-reviewed scientific journal covering theoretical, observational, and instrumental astronomy and astrophysics. The journal is run by a Board of Directors representing 27 sponsoring countries plus a r ...

'', and ''

Monthly Notices of the Royal Astronomical Society ''Monthly Notices of the Royal Astronomical Society'' (MNRAS) is a peer-reviewed scientific journal covering research in astronomy and astrophysics. It has been in continuous existence since 1827 and publishes letters and papers reporting orig ...

''.

Awards and honors

* In 1898, Denning won the Gold Medal of the Royal Astronomical Society. * He also won the Donohoe Comet Medal for his July 23, 1890 discovery of a comet. *Such was his standing in the astronomical community that following his death a memorial tablet was fixed to his house. * Crater '' Denning'' on the Moon as well as the Martian crater '' Denning'' were named after him in 1970 and 1973, respectively. * Asteroid 71885 Denning, discovered by the Spacewatch program in 2000, was named in his memory. The official was published by the

Minor Planet Center The Minor Planet Center (MPC) is the official body for observing and reporting on minor planets under the auspices of the International Astronomical Union (IAU). Founded in 1947, it operates at the Smithsonian Astrophysical Observatory. Function T ...

on 4 October 2009 ().

References

* Phil Williams (July 2015) "William Frederick Denning F.R.A.S." Liverpool Astronomical Society Newsletter (July 2015, pp,4–6)

External links

*
Telescopic work for starlight evenings
Cornell University Library Historical Monographs Collection.
W. F. Denning – The Doyen of Amateur Astronomers
Short biography by Martin Beech, Campion College, The University of Regina, Canada {{DEFAULTSORT:Denning, William Frederick 1848 births 1931 deaths 19th-century British astronomers Recipients of the Gold Medal of the Royal Astronomical Society 20th-century British astronomers