Before, ‘The cosmos is all there is, all there ever was, all there ever will be,’ there was, ‘The stars belong to everyone,’ the watch-phrase of a woman who spent three decades in energizing the wider world, through her newspaper columns and television appearances, with a profound curiosity about the stars above them. She was Helen Sawyer Hogg (1905 – 1993) and to read her words is to be captivated immediately and profoundly by her infectious enthusiasm for the stuff of the night sky.
She was born and educated in Massachusetts, having graduated a year early from high school and been selected personally by astronomical legend Annie Jump Cannon to receive a scholarship that allowed her to study at Radcliffe with Harvard Observatory director Harlow Shapley. Shapley and Sawyer were both passionate about globular clusters, spherical collections of stars held tightly together by gravity. Studying the variable stars (stars whose brightness waxes and wanes periodically) in those clusters stood a tantalizing chance of answering big questions about the size and age of the galaxy, as well as its development.
Sawyer worked with Shapley throughout the late Twenties in classifying the known clusters according to the stellar concentrations at their core, developing in the process the Shapley-Sawyer Concentration Class scale. During her time at Radcliffe, she met and fell in love with Frank Hogg, a stellar spectroscopy student who she went on to marry in 1930. Until Hogg’s tragic death at the age of 46 in 1951, he and Sawyer shared a life of mutual intellectual respect that serves as a happy counterpoint to the tragic marital tales of Mileva Maric and Harriet Brooks.
Together, they moved to Canada in 1931 to study first at the Dominion Astrophysical Observatory’s 72 inch reflecting telescope in Victoria, and after 1935 at the cutting edge David Dunlap Observatory at the University of Toronto, where Sawyer would remain the rest of her career. During her first years as a professional astronomer, she had three children and, rather than giving up her career, she integrated them into her nightly routine. While she sat on her observation platform dozens of feet in the air, her husband monitored the observatory control mechanisms below, keeping a watch on the baby. When the child cried, Hogg would descend, feed her, and then get right back up on the platform to continue her observations.
It's one of science’s most beautiful images of a research-oriented family working together, sharing duties and supporting each other’s work.
The work itself required patience on the superhuman scale. To produce clear photographs, Sawyer had to remain on her perch, eye glued to the eyepiece for as much as an hour at a time in order to make minute adjustments on the fly to the slowly developing globular image. Blinking was allowed, so long as you didn't make too much of a habit of it.
Over five decades, Sawyer produced two thousand photographic plates of globular clusters, but with that her work was hardly begun, for then she had to bend herself to the task of analyzing them, superimposing images over their negatives, and employing a blink microscope to attempt to identify the variable stars that held the key to the clusters’ age and distance. She produced three master catalogues over the course of her career, with a fourth in the works at the time of her death, which not only published new statistical data on thousands of known globular variables, but added over a hundred new variable stars she discovered herself.
Sawyer found that, of 130 known globular clusters, only 108 of them had any variable stars, and only eleven of those contained more than fifty variable stars, providing important clues about the evolution of the clusters. In addition, her findings supported the earlier work of Pieter Oosterhoff that variables in clusters were found in two varieties, one metal rich (Population I), the other metal poor (Population II). The relative abundance of heavier elements is an important measure of a star’s age – the younger you are, the more heavy elements you tend to have. The differences in composition Sawyer uncovered contributed to disproving the reigning theory that all the stars in the galaxy were the same age. The static universe gave way to a vision of stars emerging, dying, and producing in their turn new stars, and Sawyer’s meticulous analysis and cataloguing helped pave the way for that vision.
As significant as her work was to the astronomical community (so significant that in 1946 she was the first woman elected to the Royal Society of Canada in physical science), most of us know and love her from her thirty years writing the weekly column, With the Stars in the Toronto Star. That column began in 1951, the year Sawyer’s husband died, and a full 29 years before Carl Sagan’s Cosmos brought popular astronomy into American living rooms. In that space, she talked not only about the exciting picture of the universe being unveiled every day by professional astronomers, but the breath-taking phenomena available to us all.
Photo: University of Toronto
In 1976, she reworked her columns into a beautiful book, The Stars Belong to Everyone, which begins with sentiments so charming and inspiring that I have really no choice but to quote them at length:
The first day in my new post I was interviewed by a reporter who asked brightly, ‘Have you brought your telescope to Washington with you?’ I had to confess I had not. ‘My telescope’ is a little job weighing 40 tons, with a revolving shelter weighing 80 tons. But after the reporter left, I realised that I had brought to Washington my capacity to enjoy the heavens. The beautiful phenomena attending moonrise and moonset and sunrise and sunset, the annual showers of shooting stars, Venus as evening star, the old moon in the new moon’s arms – all these and many more were just as enjoyable and just as attainable for me as they would be if a giant telescope were standing by my side.
Many people tend to postpone their enjoyment of the stars because they are constantly with us, but the iridescence of the twilight bow or the orange harvest moon rising slowly over a smoky fall landscape are celestial real-life scenes to look forward to from night to night or year to year. Very little time is required to see and enjoy the beauties of the sky; once you come to know them, they never lose their appeal.
If you are not, after reading those lines, compelled to go out tonight and put your back to the setting sun to enjoy the phenomenon of the twilight bow, then you are truly a lost soul and nothing can save you.
Sawyer also communicated her love of the stars on television, where, an irresistibly eloquent and passionate grandmotherly figure, Canadians fell in love with her all over again. Her degrees and honours are too extensive to list, as are the number of people working in astronomy today who owe their early inspiration to Sawyer’s writings. With 200 papers of hard science, and thirty years of popular journalism under her belt, she set a standard by which to measure Sagan, Tyson, and all who might come after, discovering the sky’s secrets and taking the rest of us along for the ride.
FURTHER READING:
You have to find a copy of The Stars Belong to Everyone, buy it, and read it. That's not even a question. Has astronomy moved on since 1976? Oh very yes. Will that keep you from being changed and energised from reading this book? Oh very no. Finding books about Sawyer-Hogg is a trickier proposition. The great women in science pioneer Edna Yost dedicates a nice section to her in Women of Modern Science (1966), but Sawyer lived and worked a full two decades after that. To complete the story, head to the Astronomical Society of the Public’s lovely obituary of her, written by Judith L. Pipher.
If you'd like to read more about women astronomers like this one, check out my History of Women in Astronomy and Space Exploration, which you can order from Amazon, or from Pen and Sword US or UK.
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