Yet this fact alone makes her one of the most renowned geodesists of all times, because, according to Chovitz, the third quarter of the twentieth century witnessed "the transition of geodesy from a regional to a global enterprise.

[5] Her teachers Moritz Schlick and Hans Hahn were among the luminaries of the Vienna Circle; and her fellow students included physicist Victor Weisskopf, sociologist Paul Lazarsfeld, and social psychologist Marie Jahoda.

Her father, Rabbi Armand Aharon Kaminka [de], was head of the Maimonides Institute, and regularly led high holiday services at the famed Vienna Musikverein.

Looking for jobs, Fischer first worked as a seamstress’ assistant, then she graded blue books for Wassily Leontief at Harvard and for Norbert Wiener at the Massachusetts Institute of Technology (MIT).

She taught mathematics at Brown and Nichols Preparatory School in Cambridge, and then at Sidwell Friends in Washington, D.C. After World War II, and after her son, Michael, born in 1946, had reached school age, she found a job at the then Army Map Service,[6] now the National Geospatial-Intelligence Agency and the Army Geospatial Center in Potomac, Md., working under John A. O'Keefe in the Geodesy Branch and rising through the ranks to become the chief.

At the very beginning of her career in mathematics and geodesy, Dr. Fischer had quickly taught herself the basics of geodetic tables, datums, transformations, gravity studies, astronomy, long lines, flare triangulation, and guided missile ballistics.

Fischer disagreed with the established figure for the oblateness of the Earth (the fraction by which the polar axis is foreshortened by the equatorial radius), which had remained unchallenged since 1924.