As he approached the age of 50, Hubert Reeves was at the peak of his professional career. A noted astrophysicist, the Quebec-born scientist had made his career in France, where he lectured and conducted research. But he had other ambitions, to spread his love of science and the cosmos to a broader public.
He long had a gift of explaining the mysteries of the universe to the layman and had collaborated on a book for children about the sun but he wanted to produce a more substantial book for adults.
On vacations at a family resort in the south of France, he would talk about the stars, black holes and the possibility of extraterrestrial life to fellow holidaymakers, often showing slides on the wall of the cafeteria in the evenings.
A friend suggested that he put these thoughts into a book. Borrowing a phrase from the French poet Paul Valéry, Dr. Reeves called the book Patience dans l’Azur. (It’s known in English as Atoms of Silence: An Exploration of Cosmic Education.)
Dr. Reeves tried to get publishers interested but he was greeted with 30 rejections. They didn’t see a market for the work or complained that it would be too expensive to produce. A physicist friend finally suggested publishing the book in a science collection put out by Éditions du Seuil.
The book was published in 1981 to good reviews. The magazine L’Express marvelled at how “Reeves turns astrophysics into an epic saga.” But sales were slow at first, until Dr. Reeves was invited to appear on Apostrophes, a popular literary talk show on French TV. With his wild white hair and beard, his twinkling eyes and lilting Quebec accent, he was a natural communicator. Sales took off and the book became a massive bestseller in France and was translated into 25 languages.
Dr. Reeves, who died on Oct. 13 in Paris at the age of 91, became a renowned popularizer of science, a frequent presence on TV, a sought-after speaker in the French-speaking world and author of more than 40 books, including several titles for children. He became the French equivalent of Carl Sagan, the late American astronomer and science communicator, as well as a leading environmentalist, arguing that humankind was on the path of self-destruction.
“We aren’t the chosen species,” Dr. Reeves said in 2002. “There have been 10 million animal species so far and nine million have been eliminated. Nature can do without us but she won’t eliminate us. But we might eliminate ourselves.”
French President Emmanuel Macron paid homage to Dr. Reeves on his death as “a highly skilled scientist and an exceptional popularizer” as well as a tireless defender of nature. He also got praise in Canada, where he was an associate professor at the University of Montreal.
“He had a huge following in Quebec,” said David Suzuki, who shared a stage with him in discussions on the environment. “We were right down the line similar in our environmental concerns.” Dr. Suzuki, a geneticist, said he and Dr. Reeves came at their environmentalism from opposite directions. “I was focused on molecules and genes. He was focused on the stars but it’s not a surprise that we would come together.”
Hubert Reeves was born in Montreal on July 13, 1932, the third of four children of Joseph-Aimé Reeves, a shoe salesman, and his wife, Manon Beaupré.
He grew up in a large Victorian-style family home in the town of Léry, on the south shore of Lac St-Louis, west of Montreal, where as a boy he discovered the natural world by exploring nearby islands in the St. Lawrence River and perusing the skies as an amateur astronomer.
During the Second World War, his family moved to Montreal, where he pursued his studies at Collège Brébeuf. He described himself as an average student, aside from math, in which he excelled. At 17, he had the opportunity to spend a month at Harvard University’s observatory near Boston. He became hooked on becoming an astronomer.
He earned a bachelor of science degree at the University of Montreal and a master’s degree in physics at McGill University, moving to Cornell University for his PhD. There he studied under some of the greatest physicists of the era, many of whom had worked on the creation of the atomic bomb.
The young scientist was enthralled. “The atmosphere was exalting,” he recalled in his memoir, Je n’aurai pas le temps, published in 2014. “I felt immersed in a bath of science and creativity that was as interesting intellectually as it was profoundly emotional.”
After earning his doctorate, Dr. Reeves returned to teach physics at the University of Montreal but was also hired as a consultant by the U.S. National Aeronautics and Space Administration for its burgeoning space program. For a few years, he and his wife, Francine Brunel, would commute between Montreal and New York with their four young children.
Dr. Reeves soon found himself caught up in the nationalism sweeping Quebec in the 1960s. His university colleagues insisted on assigning only French-language science texts even though there were 10 times as many English books available. Then his university came up with the idea of building a particle accelerator. Governments liked the idea and suggested that the University of Montreal join up with McGill on the project.
When it became clear that English would be the language of the new lab, Dr. Reeves’s colleagues objected and the project died. Dr. Reeves decided it was time to leave Quebec. “I was very disappointed and more than ever, I decided to get some fresh air.” As his son Benoît, a conductor, musician and science popularizer, said from Paris, “Nobody is a prophet in their own land.”
After a year teaching at the Université Libre de Bruxelles in Belgium, Dr. Reeves moved to Paris as research director at France’s Centre national de la recherche scientifique (CNRS). It was the start of a more than five-decade-long career in France, where he became a citizen.
He travelled the world giving lectures, including in the Soviet Union at the height of the Cold War, but his growing fame and frequent absences took a toll on his marriage, which dissolved in the late 1970s. It was a breakup he later regretted, saying he tried to make up for it by spending more time with his grandchildren.
“My father was a great raconteur,” his son Benoît said. “He loved to tell stories and from our earliest childhood, he would love to take us in our sleeping bags to the empty lot across from our house in Laval [a Montreal suburb] to show us the stars.”
“His passion to share his knowledge with the public was extraordinary,” his son continued.
With his second wife, journalist Camille Scoffier-Reeves, Dr. Reeves purchased an estate in Malicorne, a village in Burgundy, where he became increasingly committed to restoring the environment. He favoured cedars of Lebanon, sequoias and ginkgos, all of which can live for 1,000 years or longer. “Trees are my children,” he once said. “I watch them grow up. I watch them develop. I come to see them.”
In 2001, he became chair of Humanité et Biodversité, a French environmental group and a leader in the fight against ecological degradation. “We’re destroying our planet. We have undertaken a war against nature. If we win, we’re lost.”
His son said Dr. Reeves was convinced that it wasn’t important to be optimistic or pessimistic in the defence of the environment but to be “determined.”
Dr. Reeves was honoured with the Einstein Medal in 2001 for his scientific work on the density of the universe and received numerous honorary degrees. He was named an officer of the Order of Canada in 1991 and promoted to companion in 2003. He was appointed an officer of France’s Legion of Honour in 1991 and later promoted to commander. An asteroid was named in his honour.
Despite his acclaim, Dr. Reeves remained approachable and unpretentious. “He was a very sweet guy, very warm,” said Donald Winkler, a Montreal translator, who translated four of Dr. Reeves’s books into English. Mr. Winkler recalls in particular Dr. Reeves telling him that he thought that one of his English versions read better than the original. “That was a very nice thing to say.”
Dr. Reeves leaves his wife, Ms. Scoffier-Reeves; his children, Gilles, Nicolas, Benoît and Evelyne; and eight grandchildren.