Maria Mitchell (Nantucket, 1818 – Lynn, 1889), US astronomer, the third woman to discover a comet. In 1835, she opened her own school where she developed experimental teaching methods and also allowed non-white children to attend at a time when public schools were still segregated. She became involved in the anti-slavery movement by refusing to wear clothes made from Southern cotton. She also fought for women's suffrage and education. She helped found the Association for the Advancement of Women to promote the role of women in higher education.