Harry Hemley Plaskett FRS (July 5, 1893 – January 26, 1980) was a Canadian astronomer who made significant contributions to the fields of

solar physics Solar physics is the branch of astrophysics that specializes in the study of the Sun. It deals with detailed measurements that are possible only for our closest star. It intersects with many disciplines of pure physics, astrophysics, and compu ...

astronomical spectroscopy Astronomical spectroscopy is the study of astronomy using the techniques of spectroscopy to measure the spectrum of electromagnetic radiation, including visible light, ultraviolet, X-ray, infrared and radio waves that radiate from stars a ...

and

spectrophotometry Spectrophotometry is a branch of electromagnetic spectroscopy concerned with the quantitative measurement of the reflection or transmission properties of a material as a function of wavelength. Spectrophotometry uses photometers, known as sp ...

. From 1932 to 1960, he served as the

Savilian Professor of Astronomy The position of Savilian Professor of Astronomy was established at the University of Oxford in 1619. It was founded (at the same time as the Savilian Professorship of Geometry) by Sir Henry Savile, a mathematician and classical scholar who was ...

at the

University of Oxford , mottoeng = The Lord is my light , established = , endowment = £6.1 billion (including colleges) (2019) , budget = £2.145 billion (2019–20) , chancellor ...

, and in 1963 was awarded the

Gold Medal of the Royal Astronomical Society The Gold Medal of the Royal Astronomical Society is the highest award given by the Royal Astronomical Society (RAS). The RAS Council have "complete freedom as to the grounds on which it is awarded" and it can be awarded for any reason. Past awar ...

Life

Harry Hemley Plaskett was born in

Toronto Toronto ( ; or ) is the capital city of the Canadian province of Ontario. With a recorded population of 2,794,356 in 2021, it is the most populous city in Canada and the fourth most populous city in North America. The city is the anch ...

Ontario Ontario ( ; ) is one of the thirteen provinces and territories of Canada.Ontario is located in the geographic eastern half of Canada, but it has historically and politically been considered to be part of Central Canada. Located in Central C ...

on July 5, 1893. His parents were Rebecca Hemley and

John Stanley Plaskett John Stanley Plaskett (November 17, 1865 – October 17, 1941) was a Canadian astronomer. Career He worked as a machinist, and was offered a job as a mechanician at the Department of Physics at the University of Toronto, constructing appar ...

, who at the time was working as a machinist in the Department of Physics at the

University of Toronto The University of Toronto (UToronto or U of T) is a public university, public research university in Toronto, Ontario, Canada, located on the grounds that surround Queen's Park (Toronto), Queen's Park. It was founded by royal charter in 1827 ...

, but who would later go on to become the first director of the

Dominion Astrophysical Observatory The Dominion Astrophysical Observatory, located on Observatory Hill, in Saanich, British Columbia, was completed in 1918 by the Canadian government. The Dominion architect responsible for the building was Edgar Lewis Horwood. The main instrument ...

in Victoria, and a Gold Medal winner in his own right. After receiving his B.A. from

in 1916, he joined the Canadian Corps, serving in the field artillery in France from 1917-1918. Following this, and a year spent working with Professor

Alfred Fowler Alfred Fowler, CBE FRS (22 March 1868, in Yorkshire – 24 June 1940) was an English astronomer. Early life and career He was born in Wilsden on the outskirts of Bradford, Yorkshire and educated at London's Normal School of Science, w ...

at Imperial College, he returned to Canada, and was appointed to the staff of the

Victoria Victoria most commonly refers to: * Victoria (Australia), a state of the Commonwealth of Australia * Victoria, British Columbia, provincial capital of British Columbia, Canada * Victoria (mythology), Roman goddess of Victory * Victoria, Seychelle ...

, B.C. In 1928, he was appointed Professor of Astrophysics at

Harvard University Harvard University is a private Ivy League research university in Cambridge, Massachusetts. Founded in 1636 as Harvard College and named for its first benefactor, the Puritan clergyman John Harvard, it is the oldest institution of high ...

, and in 1932 succeeded H. H. Turner as

at the University of Oxford. In May, 1936 he was elected a

Fellow of the Royal Society Fellowship of the Royal Society (FRS, ForMemRS and HonFRS) is an award granted by the judges of the Royal Society of London to individuals who have made a "substantial contribution to the improvement of natural knowledge, including mathemat ...

. He was president of the

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

just after World War II. His time at Oxford was interrupted by war service: from 1939 to 1940, he was an anti-aircraft officer, and from 1940 to 1944 he worked on experimental navigation for the Ministry of Aircraft Production. From 1951 to 1955 he worked alongside Walter Stibbs. He retired from Oxford in 1960, becoming a Professor Emeritus of the university, but remained active in astronomical research almost until the end of his life.

Family

He had married in 1921 Edith Alice Smith, with whom he had two children, Barbara and John Stanley. They were to remain married until his death in 1980.

Honors

The asteroid 2905 Plaskett, discovered by

Edward Bowell Edward L. G. "Ted" Bowell (born 1943 in London), is an American astronomer. Bowell was educated at Emanuel School London, University College, London, and the University of Paris. He was principal investigator of the Lowell Observatory Near-Earth ...

in 1982, was named in his and his father's memory.

References

1893 births 1980 deaths Military personnel from Toronto Royal Regiment of Canadian Artillery officers Canadian military personnel of World War I Canadian Army personnel of World War II Scientists from Toronto 20th-century Canadian astronomers University of Toronto alumni Harvard University faculty Recipients of the Gold Medal of the Royal Astronomical Society Canadian Fellows of the Royal Society Savilian Professors of Astronomy Presidents of the Royal Astronomical Society Fellows of the American Physical Society {{astronomer-stub