Unfortunately, women in those days weren't recognized in many disciplines, so some took a man's first name, or had their project taken over by a man. Here, Maria was represented by her husband, Gottfried Kirch, as he was already highly esteemed by the king. And when Gottfried died, his son took over his project. 

So, as I was saying, Gottfried died in 1710 and Kirch petitioned the Royal Academy of Sciences in Berlin to allow her and her son Christfried to continue producing calendars. Except that it was an inexperienced astronomer, Johann Heinrich Hoffmann, who was appointed Astronomer Royal with responsibility for producing calendars. However, Kirch was allowed to stay in the accommodation that had been provided for his family. In 1716, Hoffmann died and Christfried was appointed Astronomer Royal. Kirch and two of his daughters, Christine and Margaretha, worked as Christfried's assistants. In 1717, Kirch was reprimanded by the Academy for playing too large a role in the life of the observatory, and was expelled from her residence at the observatory, thus ending her scientific career.