Her father, Alfred Myer Hellman, was an obstetrician and a collector of rare books; her mother Clarisse (née Bloom) later served as the only female member of the board of directors of Sydenham Hospital.

[5] She graduated from the Horace Mann School in 1926, and earned a bachelor's degree in mathematics and astronomy (with election to Phi Beta Kappa) from Vassar College in 1930.

[1][5][6] In it, she credits Columbia professor Frederick Barry for supervising her doctoral research, and thanks Sarton and Lynn Thorndike for their encouragement, suggestions, and criticism.

In 1951, she was appointed to the faculty of the Pratt Institute, in the Department of Social Studies, and in the early 1950s she led the effort to found The New York Section of the History of Science Society.

As the book briefly outlines in its conclusion, and as historians of science came to realize, in large part based on Hellman's work, these observations of the comet played a key role in the success of the Copernican Revolution of the early 17th century, in which the earth-centered model was supplanted by the sun-centered one.

Writing at the time of its first publication, historian Pearl Kibre sees the book as reflecting the continuity of medieval thought, rather than the break that was soon to come.

[12] In contrast, at the book's republication in the 1970s, historian of science William H. Donahue credits Hellman with the recognition of the comet's role in the change in cosmology, calls her choice to include non-astronomical sources "admirable and powerful", and writes that, by focusing less on theoretical debates and more on thoroughly cataloging the works of the time, Hellman's book has become timeless, "ever assured a place in the first rank of works on the history of astronomy".

[11] By 1995, Albert van Helden, the Lynette S. Autrey Professor of History at Rice University, called her book "the standard treatment of the comet of 1577".

[16] Writing in Science, reviewer William D. Stahlman calls Caspar's book the definitive biography, and Hellman's translation excellent, smooth, and long-awaited.