The Bruce Medalists


  Photo courtesy National Research Council of Canada, Herzberg Institute of Astrophysics, Dominion Astrophysical Observatory
John Stanley Plaskett
17 November 1865 1932 Bruce Medalist 17 October 1941

“Jack” Plaskett began his college education at age 24, while a mechanic employed by the University of Toronto physics department, and graduated at 33. He was one of the original staff of the Dominion Observatory in Ottawa in 1903. He designed an exceptionally efficient spectrograph for the 15-inch refractor and measured radial velocities and found orbits of spectroscopic binary stars. He successfully lobbied for and designed and supervised construction of the 72-inch reflector built for the new Dominion Astrophysical Observatory in Victoria and was appointed its first director in 1917. There he extended the work on radial velocities and spectroscopic binaries and studied spectra of O and B-type stars. He was able to confirm the Lindblad-Oort model of galactic rotation with these data, and he also did important work on interstellar calcium. He was a leader in building Canadian astronomy.

Presentation of Bruce medal
Joy, Alfred H., PASP 44, 5-20 (1932).

Other awards
American Academy of Arts & Sciences, Rumford prize, 1930.
National Academy of Sciences, Henry Draper medal, 1934.
Royal Astronomical Society, Gold medal, 1930, presented by A.C.D. Crommelin, MNRAS 90, 466-477 (1930).
Royal Society of Canada, Flavelle medal, 1932.

Some offices held
Royal Astronomical Society of Canada, President, 1914-15.

Biographical materials
Beggs, Mike, Canada Heirloom Series, John Stanley Plaskett — Canada's Father of Modern Astronomy
Broughton, R. Peter, Northern Star: J.S. Plaskett (Univ. of Toronto Press, 2018). [info]
Jarrell, Richard A., Biographical Encyclopedia of Astronomers (Springer, NY, 2007), pp. 912-13.
North, J.D., Dictionary of Scientific Biography 11, 18-19.
Shell, Barry, Great Canadian Scientists
Spencer Jones, H., Obituary Notices of Fellows of the Royal Society 4, 67-82 (1942).
Tenn, Joseph S., “John S. Plaskett: The Twenty-Seventh Bruce Medalist,” Mercury 24, 1, 34 (1995).

Aitken, Robert G., PASP 53, 323-24 (1941).
Beals, C.S., JRASC 35, 401-411 (1941)
Bok, Bart J., Science 94, 453 (1941).
Chant, C.A., “John S. Plaskett at the University of Toronto,” JRASC 35, 412-414 (1941).
Hogg, Frank S., MNRAS 102, 70-73 (1942).
Petrie, R.M., Popular Astronomy, 50, 1, 2-5 (1942).
Redman, R.O., Observatory 64, 207-211 (1942).
Sanford, R.F., Ap. J. 98, 137-141 (1943).

Portraits (another)

Named after him
Lunar crater Plaskett.
Minor Planet #2905 Plaskett (with his son, Oxford astronomer H.H. Plaskett).
Plaskett’s Star, long the most massive binary star system known.
The Plaskett Telescope at the Dominion Astrophysical Observatory.
Royal Astronomical Society of Canada and the Canadian Astronomical Society, The Plaskett Medal (more).

More references

The Bruce Medalists

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