Ross Mark Henkelman was born in Oshawa, Ontario on December 1st, 1946, and died at home, surrounded by family, on June 28th, 2024. Mark tied as oldest child, the twin to Mary Henkelman, of Victor Albert Henkelman and Jean Elizabeth Henkelman (née Alloway) and was older brother to Anne Bigham (née Henkelman). Mark married Jannie (née Smits) in 1970 and together they had three children: Jonathan, Graeme, and Erika. He was a demanding and proud father who passed along his curiosity, creativity of thought, strong work ethic, and love of the natural world.

Mark was always inquisitive, frequently asking as a child: “How does it work?” His sharp intellect, curiosity, and interest in science led him to study physics. After obtaining his PhD in electron microscopy in 1973, Mark became interested in Magnetic Resonance Imaging (MRI) and joined the faculty at the University of Toronto where he successfully undertook the challenge of bringing this new technology to Canada. In 1989, he joined Sunnybrook Health Sciences Centre to lead their new research institute and to focus his own research efforts in the field of MRI. In 2000, Mark shifted his research from imaging people to mice, conceptualizing and creating the Mouse Imaging Centre (MICe) at The Hospital for Sick Children. His work mapped how genetic changes result in physical differences, untangling the complex interplay between genes and health. Mark leaves behind a legacy of scientific innovation dedicated to advancing imaging in medicine and research. His lifelong work has been recognized by the Gold Medal of the International Society for Magnetic Resonance in Medicine, the Killam Memorial Prize, and his induction as an Officer of the Order of Canada.

Mark enjoyed the outdoors, finding wonder in everything from the smallest of viruses to the vastness of the universe. He was an avid reader who seemed to know something about everything, always striving to learn more. He went on frequent canoe trips and had a special place in his heart for the Ontario provincial parks. While he spent most summers at the family cottage in Muskoka, delighting in showing off its beauty from the “slow boat,” he also appreciated what the larger world had to offer and travelled extensively with family, friends, and colleagues. His travels were diverse: from diving in many of the world’s waters, to kayaking in the Canadian Arctic, hiking in Switzerland, safaris in South Africa, biking in Holland, boating on the Rhine, and fishing in Nova Scotia. He enjoyed the arts: theatre in London, concerts in Vienna and Paris, architecture in Morocco and Spain. He also loved food, sampling new flavours everywhere he went, and cooking up an excellent spread for family and friends at home. Mark had a powerful impact on all who knew him in every sphere of his life. He was a father, a friend, a mentor, and a teacher. He was brilliant, frank, quick-witted, proud, and generous. He will be missed, and he will not be forgotten.

A memorial to celebrate Mark’s life will be held at Mount Pleasant Cemetery on November 2 at 12:30, 375 Mount Pleasant Road, Toronto, Ontario. A light lunch will be served at 2:00 p.m.