BOOK SPECIAL... The Greatest Science Books of 2016 13.THE GLASS UNIVERSE

 The Greatest


 Science

 Books of 2016

13.THE GLASS UNIVERSE

Predating NASA’s women mathematicians by a century was a devoted team of female amateur astronomers — “amateur” being a reflection not of their skill but of the dearth of academic accreditation available to women at the time — who came together at the Harvard Observatory at the end of the nineteenth century around an unprecedented quest to catalog the cosmos by classifying the stars and their spectra.

Decades before they were allowed to vote, these women, who came to be known as the “Harvard computers,” classified hundreds of thousands of stars according to a system they invented, which astronomers continue to use today. Their calculations became the basis for the discovery that the universe is expanding. Their spirit of selfless pursuit of truth and knowledge stands as a timeless testament to pioneering physicist Lise Meitner’s definition of the true scientist.

The “Harvard computers” at work, circa 1890.

Science historian Dava Sobel, author of Galileo’s Daughter, chronicles their unsung story and lasting legacy in The Glass Universe: How the Ladies of the Harvard Observatory Took the Measure of the Stars (public library).

Sobel, who takes on the role of rigorous reporter and storyteller bent on preserving the unvarnished historical integrity of the story, paints the backdrop:

A little piece of heaven. That was one way to look at the sheet of glass propped up in front of her. It measured about the same dimensions as a picture frame, eight inches by ten, and no thicker than a windowpane. It was coated on one side with a fine layer of photographic emulsion, which now held several thousand stars fixed in place, like tiny insects trapped in amber. One of the men had stood outside all night, guiding the telescope to capture this image, along with another dozen in the pile of glass plates that awaited her when she reached the observatory at 9 a.m. Warm and dry indoors in her long woolen dress, she threaded her way among the stars. She ascertained their positions on the dome of the sky, gauged their relative brightness, studied their light for changes over time, extracted clues to their chemical content, and occasionally made a discovery that got touted in the press. Seated all around her, another twenty women did the same.

The “computers” working at the Harvard Observatory, with Williamina Fleming (standing) supervising. (Harvard University Archives)

Among the “Harvard computers” were Antonia Maury, who had graduated from Maria Mitchell’s program at Vassar; Annie Jump Cannon, who catalogued more than 20,000 variable stars in a short period after joining the observatory; Henrietta Swan Levitt, a Radcliffe alumna whose discoveries later became the basis for Hubble’s Law demonstrating the expansion of the universe and whose work was so valued that she was paid 30 cents an hour, five cents over the standard salary of the computers; and Cecilia Helena Payne-Gaposchkin, who became not only the first woman but the first person of any gender to earn a Ph.D. in astronomy.

Helming the team was Williamina Fleming — a Scotswoman whom Edward Charles Pickering, the thirty-something director of the observatory, first hired as a second maid at his residency in 1879 before recognizing her mathematical talents and assigning her the role of part-time computer.

BRAIN PICKINGS