- Person
- 1943 - 2021
Charles Thomas (Tom) Bolton (15 April 1943 – 4 February 2021) was white astronomer and Professor Emeritus at the University of Toronto’s Department of Astronomy and Astrophysics. Academically, he is best known as one of the first astronomers to discover observational proof of the existence of black holes. He is also known internationally for his fight against light pollution in Richmond Hill which led to the establishment of the first municipal light pollution regulation in Canada.
Education
Bolton was born in Camp Forrest, a World War II military base east of Tullahoma, Tennessee. He was raised in Illinois where he later completed his B.Sc. in Astronomy at the University of Illinois in 1966. Afterwards, he received his M.Sc. (1968) and Ph.D. (1970) from the University of Michigan during which he became an expert in astronomical spectroscopy. His doctoral thesis, Spectral Synthesis of Low Dispersion Luminosity Criteria in A and F Type Stars was supervised by Charles R. Cowley. In September 1970, Bolton began a postdoctoral fellowship at the University of Toronto where he worked with Robert Garrison and John Heard on spectral classification and radial velocity research programs at the David Dunlap Observatory (DDO).
University of Toronto and the David Dunlap Observatory
While working as a postdoc, Bolton began teaching as an adjunct professor at the University of Toronto’s Department of Astronomy (1970 – 1971), Scarborough College (1971 – 1972), and Erindale College (1972 – 1973). In 1973, he was hired as an Assistant Professor (1973 – 1976) before becoming an Associate Professor (1976 – 1980), eventually receiving full tenure in 1980. Throughout his career, Bolton served on numerous committees within the Department of Astronomy, including the Chant Committee (1978 – 1979), Colloquium Committee (1985 – 1986), Graduate Program Degree Committee (1992 – 1993), Curriculum Review Committee (1990 – 1991), Executive Committee (1991 – 1994), as well as several search and tenure committees at the departmental and university levels.
Bolton’s research primarily involved the spectroscopic observation of stars, with a particular focus on hot massive stars, variable stars, binary systems, and stars with strong magnetic fields or peculiar chemical properties. His success as an astronomer began early in his academic career. In 1970, as a pioneer of spectral synthesis, Bolton developed a computer model for stellar atmospheres capable of generating large regions of spectra that were comparable to spectral data from real stars. This technique would eventually become part of the standard skillset of stellar astronomers.
Shortly after, Bolton presented his most celebrated contribution to astronomy when he discovered and published the first irrefutable evidence for the existence of a black hole in 1972. Much of Bolton’s subsequent work has also contributed heavily to the field’s understanding of stellar evolution. His work has been published in over 100 academic journal articles, often co-authored by his students or collaborating astronomers from around the world.
In addition to his research, Bolton dedicated much of his time to administrative roles and improving the facilities at the DDO. He served as the DDO’s Associate Director (1978 – 1994) as well as the supervisor of the 74-inch telescope (1974 – 1984) and darkroom (1976 – 1983). Between 1970s and 1990s, Bolton led several campaigns to upgrade and modernize the equipment at the observatory including the acquisition of a PDS microdensitometer, an image slicer for the cassegrain spectrograph, and a CCD camera for the 74-inch telescope. He also chaired numerous committees, including the Telescope Scheduling Committee (1971 – 1984); Shop Committee (1982 – 1983; 1992 – 1994); Safety Committee (1981 – 1994); and the DDO Review Committee (1992 – 1997).
As the DDO’s Light Pollution Officer (1972 – 1997), Bolton fought against the rapidly increasing levels of light pollution in the Greater Toronto Area which threatened the DDO’s ability to conduct research. By 1986, Bolton succeeded in generating enough negative publicity against developers in the Town of Richmond Hill that the Town
agreed to pass a light pollution abatement by-law and authorized Bolton to review and approve the lighting plans for all new developments until the by-law could be implemented. During this time, Bolton also helped to draft the by-law which was established as the first of its kind in Canada in 1995.
Professional Activities
Outside his role at the University of Toronto, Bolton was also highly involved in the broader astronomical community. He was a founding member of the Canadian Astronomical Society (CAS) and an active member of the International Astronomical Union (IAU), Royal Astronomical Society of Canada (RASC), American Astronomical Society (AAS), Planetary Society, and the Illumination Engineering Society (IES). Within the IAU, Bolton served on Divisions G (Stars and Stellar Physics) and V(Variable Stars), as well as numerous commissions and committees including Commission 30: Radial Velocities (1976 – 1988), Commission 42: Close Binary Stars (1979 – 2015), and Commission 27: Variable Stars (1982 – 2015). Beginning in the late 1970s, Bolton also served on several peer review, scientific advisory, and observing time assignment committees for NASA’s International Ultraviolet Explorer (IUE), Hubble Space Telescope, Extreme Ultraviolet Explorer (EUVE); the Canada-France-Hawaii Telescope; the Canadian Space Agency (CSA); the National Research Council of Canada; and the Natural Sciences and Engineering Research Council of Canada (NSERC). Likewise, Bolton was passionate about public education and outreach, giving over 100 interviews for television, radio, and newspapers, as well as public talks about astronomy throughout his career.
Health and Retirement
In the early 1990s, Bolton began experiencing several health issues that forced him to take extended sick leaves and eventually, a long-term disability leave in 1997. In July 1992, Bolton was deeply impacted by the suicide of his Ph.D. student and friend, Michael Fieldus, who was within a couple of months of completing his degree. Bolton, along with the Fieldus family, petitioned to have the University grant Fieldus’ degree posthumously and worked to complete Fieldus’ thesis using the data that Fieldus had collected. Although Bolton had been able to convince the School of Graduate Studies that Fieldus’ situation would warrant consideration, their request was ultimately denied. After Fieldus’ death Bolton helped to establish the Michael S. Fieldus Award presented to students in the department who exemplified Fieldus’ leadership and academic excellence.
In 2007, the University of Toronto announced the plan to sell the DDO and the surrounding property for development. Distressed by the University’s decision, Bolton became a founding member of the DDO Defenders, a community group which sought to protect and conserve the DDO property. The efforts of Bolton and the DDO Defenders resulted in the designation of the DDO as a heritage site under the Ontario Heritage Act in 2009 and a National Historic Site of Canada in 2019. However, the sale of the DDO in June 2008 forced Bolton to vacate the Observatory. This put an early end to his career as his health issues prevented him from travelling to work at other observatories. Bolton retired and was appointed Professor Emeritus status in 2008.
Family
Bolton was born to Clifford T. and Pauline (Voris) Bolton in 1943. Prior to moving to Toronto, Bolton was married to Mary Jean Harris, separating in the mid-to-late 1970s. In 1985, Bolton met amateur astronomer Carolyn Susan Challenger through the RASC in Toronto. The couple married in 1986 and Bolton became a stepfather to her four children, David, Stephen, Craig, and Bill Hodges. Challenger died on December 7th, 2012 and Tom Bolton died on February, 4th 2021at his home in Richmond Hill.