For nearly a month, from February 11, marking the International Day of Women and Girls in Science, to March 8, the date on which International Women’s Rights Day is celebrated, eight portraits of women astronomers who have worked "for" or "with" the Paris Observatory over the last three centuries will be published on the wire.
Find out the portrait of the third woman in this collection :
Marie-Jeanne (known as Amélie) Lefrançois-de Lalande (1768-1832)
French astronomer and mathematician. Marie Jeanne De Lalande is known for her catalogs of precise star positions and her ephemerides, indispensable for position calculations at sea
Marie Jeanne Harlay was the daughter of a couple of school teachers, Jean François Harlay and Anne Elisabeth Cany. In 1788, she married Michel Lefrançois de Lalande, first cousin of Jérôme Lalande (Joseph Jérôme Lefrançois de Lalande). The newlyweds moved to Lalande’s place at the Royal College (later Collège de France).
She quickly collaborated with her husband and Jérôme Lalande in the observation and reduction of the stars which will constitute the French Celestial History published by Joseph Jérôme Lalande from 1801. She had in particular to correct the observed positions of the effects of the refraction, the nutation, the annual aberration and the precession to fix the positions on January 1, 1790.
In particular, it calculated the Tables horaires de la marine published in Abrégé de navigation historique théorique et pratique avec tables horaires (1793) by Jérôme Lalande. These tables allowed sailors to determine their position at sea by calculating the height of the Sun and stars. They earned Jérôme Lalande one of the medals that the Lycée des Arts awards to distinguished scientists and artists.
As they were observed and reduced, these stars also contributed to the annual ephemerides published from 1794 to 1806 in the Connaissance des temps (a periodical publication of the Paris Observatory since 1679). In 1799, she established a catalog of 10 000 stars.
The De Lalande crater on Venus is named in her honor.
| previous portraits : |
The Women Astronomers project at Paris Observatory
At the initiative of the working group on equality between women and men, and with the support of the presidency of the Observatoire de Paris-PSL, a committee of female and male researchers, students and doctoral students has been formed to highlight the work of women astronomers who, as much as their male colleagues, have contributed to the scientific history of the institution. These women often remained in the shadow of the private sphere, rarely co-signing the publication of their own results, or confined to the role of assistant or scientific secretary, before finally obtaining the recognized status of astronomer at the beginning of the 20th century.
In addition to a first event in the form of a few web and Twitter publications on the occasion of the International Day of Women and Girls in Science 2023, the project plans to build a documentary fund, to write wikipedia content to describe the work of the many women astronomers who have worked with the institution, and eventually an installation in the form of a portrait gallery, displayed in the buildings of the institution.
Participating in this project are Romane Cologni, Lucie Cros, Léa Griton, Mathilde Malin, Rhita-Maria Ouazzani and Gilles Theureau.