Marcia Bartusiak is a professor in the MIT Graduate Program in Science Writing and the author of seven books on the frontiers of astrophysics and its history, including her latest, “Dispatches from Planet 3.”

At first glance, it seems an odd pairing of topics: In what way could Dante, the 14th-century poet, be linked with astronomy? But to my delight Tracy Daugherty — essayist, novelist, and biographer of Joseph Heller and Joan Didion — has uncovered a small gem within the history of astronomy. Along the way, readers become acquainted with the British romantics, Australian aboriginal astronomy, the folklore of India, and brief lessons on the sun’s energy production and Einsteinian physics. “Dante and the Early Astronomer” is an eclectic and engaging look at the Victorian and Edwardian ages, from the perspective of minor-league astronomers working in the hinterlands.

The story centers on Mary Acworth Evershed (pen and maiden name M.A. Orr), an Englishwoman born in 1867. She was a lover of both poetry and the celestial sky, and a trip to Italy at the age of 20 set the foundation for her life’s quest: to closely examine all the astronomical references in Dante’s “The Divine Comedy,” not only to catch the mistakes but to find the “poetic prologue to future discoveries,” as the author puts it.

As a young woman, Mary was an accomplished amateur astronomer. Upon returning from a five-year sojourn in Australia, she published a guide to the Southern Hemisphere’s constellations and presented a paper to the British Astronomical Association (BAA) on the celestial knowledge of the continent’s indigenous peoples. The BAA was open to women (unlike the Royal Astronomical Society at the time), which allowed her to join its solar eclipse expeditions. It was during travels to Norway and Algiers for these events that she became acquainted with solar astronomer John Evershed.

Like Mary, John had been drawn to science early on, even meeting Charles Darwin as a youth. Passionate about astronomy, he built his own equipment and established a private observatory. Though not formally trained, his work so impressed Britain’s Astronomer Royal that he was invited to help direct the Kodiakanal Observatory, set atop the Palani Hills of southern India. That was the spark that finally pushed John, after five years of friendship, to propose marriage. At the age of 39 in 1906, independent-minded Mary was no longer a spinster. She had found a man who took her accomplishments seriously.

Almost immediately, the two became a team . Daugherty covers all the trials and tribulations of observing the sun in this era, a time when the source of the sun’s power was unknown and astronomers despaired that they would ever know what a sunspot was. Also on display are the growing political unrest and social environment within a lonely outpost of the British Raj on the verge of decline.

Being in India was an inspiration for Mary. The “waterfall-filled forests and lakes . . . where plums and plantains grow alongside rare kurinji flowers,” according to the author, reminded her of the geography described in sections of the “Comedy.” She soon was diligently working on her Dante project, which was eventually published as “Dante and the Early Astronomers.”

Dante lived at a time when the works of Aristotle and Ptolemy were accepted as the cosmological standard: the Earth poised at the universe’s center, with the sun, moon and planets moving around it, each set upon a crystalline sphere. Though this model was radically overturned, Mary (and others before her) were drawn to Dante’s outdated celestial descriptions for “his faithfulness to the teachings of astronomy as he had learned it,” as she put it in her book. Dante had his Aristotle, Ptolemy and Euclid down pat. “Mary understood,” writes Daugherty, “that Dante the poet possessed the impulses of a scientific researcher: a restless mind, a habit of close observation.” He took pains to get the exact annual period of the sun’s revolution around the Zodiac, somehow obtaining a value closer to modern estimates than his contemporaries. He mentioned the sun’s “flecked disc” three centuries before sunspots were recognized. And he never had a waxing crescent moon rising in the east at sunset (a mistake made so often in literature). Dante scholars came to appreciate her findings.

Others followed up. Daugherty points to later arguments that suggest Dante was ahead of his time, picturing a non-Euclidean space in his “Comedy” where God sits at a single point within a series of ever-curving spaces and radiates a brilliant light, a seemingly prescient notion of the big bang. “Dante has invented a new topological space, the 3-sphere,” or hypersphere, mathematician Mark Peterson noted in an analysis. This is all fun, yet still problematic, as such a hypothesis is based on applying modern theories to what were poetic and allegorical imaginings in the 14th century. I remain skeptical.

The book ends with the Eversheds returning to England in 1923, right after John failed to verify Einstein’s general theory of relativity because of equipment malfunctions during a solar eclipse expedition to Australia. He once again set up a private observatory and, despite his misgivings about his career accomplishments, was awarded the gold medal of the Royal Astronomical Society for his breakthroughs in the study of sunspots.

Mary died of cancer in 1949 at the age of 82. The next year, John married a family friend, Margaret Randall, 40 years his junior. He continued his solar studies for six more years until his death. As for the observatory in Kodiakanal, the direct descendants of the Indian men who assisted John and Mary in the early years of the 20th century continue the solar observations to this day.

Dante and the Early Astronomer

Science, Adventure,
and a Victorian Woman Who Opened the Heavens

By Tracy Daugherty

214 pp. $26