She was a Quaker and self-taught astronomer with a radical idea: The stars belong to us a

One of the girls asked Mitchell if she might enroll in the school. Raised like most Quakers to oppose slavery, Mitchell knew that recently debate had raged in Nantucket’s white community about the radical notion of integrating the island’s public school. Slavery had been banned in Massachusetts since the 1780s, but government, business, and education carefully kept “free” Black people on the lowest rung of the social ladder. When she met the girls’ hopeful gazes and told them yes, they could enroll, Mitchell knew that uproar might follow.

Mitchell was just 17 then, but she would go on to be the first female astronomer in the United States and one of the first in the world. “Part of what Maria Mitchell did,” says astrophysicist and University of New Hampshire assistant professor Chanda Prescod-Weinstein, “was give us a model of a community-engaged astronomer. She never thought she should just shut up and calculate.” Mitchell was principled in her views and not timid about sharing them. “She had a sense of responsibility to the broader community, from the importance of educating Black girls during a time of intense segregation to her subsequent persistent advocacy for women in science.”

Today, 133 years after her death, Mitchell’s legacy continues in institutions such as the Maria Mitchell Observatory on her native Nantucket, where director Regina Jorgenson conducts research on galaxy formation and directs an outreach program targeting students from underserved communities. “Maria Mitchell was very much ahead of her time,” Jorgenson says. “‘Learning by doing’ was her foundational philosophy. While this is fairly common pedagogical practice today, it was not at all at that time.”

The observatory’s research program, once women-only, is now mixed-gender but still women-dominated. Which, adds Jorgenson, “is extremely unusual, if not unique,” in American astrophysics. One in 20 female astronomers in the country has passed through the observatory in some fashion, creating a community of women tied together by the legacy of Maria Mitchell.

White society was not torpedoed by the education of three Black girls, it turned out, and Mitchell soon moved to other fields. She did not attend college (few colleges accepted women at that time), but within a year, she was hired as librarian of the Nantucket Atheneum. Many cities boasted an athenaeum (named for Athena, the Olympian goddess of wisdom), a combination of a subscription library, nexus of important periodicals, and lecture venue. (Many, such as Nantucket’s and Boston’s, still flourish.) Mitchell worked there for two decades. She spent spare hours devouring books and periodicals about astronomy and mathematics, while teaching herself French and German.

William Mitchell, her father, held many jobs over the years, from clerk of the Nantucket Society of Friends to banker, schoolmaster, and legislator. He even set chronometers for whaling captains who required an accurate timepiece for determining longitude. But the constant for him and his family was astronomy.

His daughter’s talents in this field were recognized early. Beginning in childhood as her father’s assistant, Maria grew ever more adept as an astronomer — which flowered into her great passion in life. By the age of 12 she was charting eclipses from the awkward little platform perched astride their steep roof.

When William was hired in 1836 as director of Pacific Bank, the job included a spacious penthouse apartment above the bank. Its flat slate roof made it easier for him and his daughter to build another observatory. For the next 11 years, she peered at the sky on most clear nights.

She had been precisely monitoring successive quadrants of the sky for years when, on October 1, 1847, the Mitchells hosted a party. It was a clear and cool night. After tea she said to the guests and her family, “Now, you must excuse me. The heavens are so clear I want to sweep the skies. Who knows what comets may be roaming at large?”

Maria donned a coat and climbed up to the roof. She peered yet again at a familiar corner of the sky — but this time she saw something new. She went downstairs and told her father what she thought she had found.

Soon partygoers heard William race downstairs from the roof. With his observing cap still pulled low over his eyes, he tore open the parlor door and exclaimed, “Maria has found a telescopic comet!”

He wrote immediately to various authorities to establish her priority. Soon the director of the US Coast Survey was writing, “We congratulate the indefatigable comet seeker most heartily on her success; is she not the first lady who has ever discovered a comet?”

She was not, but it was a rare achievement nonetheless. For millennia, these visitors to the night sky had been regarded as celestial omens, and this one bode well for Maria Mitchell. Soon popularly called Miss Mitchell’s Comet (now designated C/1847 T1), it is not a periodic visitor to the solar system, unlike the comets Halley or Hale-Bopp.

At 30, Mitchell began to receive the scientific accolades that would continue for the rest of her life. She was the first American astronomer to discover a comet. Soon Mitchell became the first woman elected to the American Academy of Arts and Sciences, and later to most of the previously all-male institutions, such as the American Association for the Advancement of Science. She became quite famous, publicly supporting feminism and abolition when it would have been easier to not do so. When Frederick Douglass first spoke to a large mixed-race audience on Nantucket in 1841, she was present, and her work was honored at the Seneca Falls Woman’s Rights Convention in 1848.

When Vassar College opened its doors in 1865, Mitchell was there as its first professor of astronomy (paid considerably less than her male colleagues). She was 47 and among the first generation of astronomers who were also college professors — a marriage of commitments that left her exhausted.

She was hugely popular with students — even revered. They helped her chart sunspots and eclipses. “We are women studying together,” she would say to launch a class. She objected to numerical grading but gave rigorous math tests. “Astronomy is not stargazing,” she insisted. “The laws which govern the motions of the sun, the earth, planets, and other bodies in the universe cannot be understood and demonstrated without a solid basis of mathematical learning.”

And Mitchell treated her students as serious scholars. One student wrote of her time at Vassar: “I have Miss Mitchell and all these grand instruments and no one here makes fun of it at all. But when I go home no one there will take any interest in astronomy. Do you think I shall be brave enough then to hold on tight to what I have begun?”

Mitchell died in 1889. In 1935, a century after she opened that school for girls, her admiring colleagues in the field named a lunar crater after her.

Thirteen years after Mitchell’s death, Nantucketers formed the Maria Mitchell Association to preserve her legacy as a scientist and teacher, which was meant, in part, to help female students study astronomy and “hold on tight” to what they began. Now the association operates two observatories, a museum at the original Mitchell home on Vestal Street — where Maria and her father observed the constellations from their roof — and an aquarium, providing many programs for scientists and the public.

Regina Jorgenson has been director of the Maria Mitchell Observatory since 2016. She began her career with a fellowship that enabled her to travel around the world and meet with women in astronomy to research the effect of different cultures on women’s potential in science. “This is a unique position for an astronomer, because it is not at an academic institute. It combines the three things I love: research, working with students, and doing public outreach.”

Under Jorgenson’s leadership, the observatory focuses on mentoring underrepresented groups at crucial stages in their careers. Thus, the array of students and speakers is quite different than in Mitchell’s time. Prescod-Weinstein, who gave a lecture for the Maria Mitchell Association last July on her research into dark matter, writes about astronomy and physics within the context of her experience as a Black woman who is also agender, representing an intersection of groups that for centuries have deliberately been excluded from science.

Prescod-Weinstein says that her night sky looks very different from Maria Mitchell’s. Mitchell was born in 1818, before the adoption of trains,…