She and her sister Christine Kirch were educated in astronomy and worked as their parents' and, later, their brother's assistants.
[2] Like her sister Christine, she was taught astronomy at the age of 10, and both initially assisted her brother Christfried with his observations.
Kirch and her sister Christine worked as assistants and made the astronomical observations and calculations for planetary ephemeris.
[2] After the Great Comet C/1743 X1 had passed the sun, Margaretha observed and drew a streaky splitting of the comet's tail on March 5, which was only observed on the following four days by Joseph-Nicolas Delisle and Gottfried Heinsius in Saint Petersburg, as well as the well-known astronomer Jean-Philippe de Chéseaux in Lausanne.
[3] Like her mother and her sister, Kirch did not receive official recognition of their professional work at the observatory.