He received his B.Sc. in 1979 from the University of Manitoba and in 1981 began his professional career working as Resident Astronomer at the University of Toronto Southern Observatory at Las Campanas, Chile.
Discovery of Supernova 1987A
On February 24, 2:40 a.m., 1987, Shelton, while working in Chile at Las Campanas Observatory for the University of Toronto, discovered a previously undetected bright light on a photograph of the Large Magellanic Cloud. Initially skeptical, Shelton went outside to look with the naked eye, and saw that the bright light was indeed present. His discovery turned out to be a supernova, the first visible to the naked eye since Johannes Kepler observed SN 1604 nearly 383 years prior.
Subsequent career and life
Shelton became a graduate student at the University of Toronto in the fall of 1987. He received his M.Sc. in 1990 and Ph.D in 1996. He has since worked as an astronomer at several observatories: Japan's 8.3-metre Subaru Telescope in Hawaii, the 1.9-metre David Dunlap Observatory in Toronto, Athabasca University north of Edmonton, and the 6.5-metre MMT Observatory south of Tucson.
Starfest. A Celebration of Astronomy (2009) (Brief bio of Ian Shelton p. 6)
Whole new science exploded with supernova discovery 20 years ago The Edmonton Journal, 25 Feb. 2007