ZACH, František Xaver
* 4. 6. 1754, Bratislava, Slovakia
† 2. 9. 1832, Paris, France
Mathematician and astronomer
Z. graduated from the Military Academy in Vienna, then studied mathematics and astronomy in London and graduated in law and philosophy at Oxford. After graduating, he became an officer in the Austrian army, and from 1775 onwards worked in London as a tutor in the house of the Saxon minister. In 1776 he began working in the service of Ernest II, Duke of Saxe-Gotha-Altenburg at Gotha. Here he was promoted to Lieutenant in 1786, then into Commander in Chief and court manager of widowed Saxony-Gothic Duchess Carolina, who he accompanied on travels through France and Italy. A year later he established a new observatory on Seeberg hill at Gotha and was its director until 1806. In 1798 he organized the first international astronomical congress there.
Between 1807 and 1813 he lived in Genoa, Naples and Kussa, where he also participated in the construction of observatories. He then founded the observatory in Geneva and managed it until 1827. From 1827 he lived in Paris, where he specialized in astronomical observation of the sun’s movement and dealt with aberration and nutation of stars. He collaborated with the Czech astronomer Martin Alois David, whom he supported at the establishment of the Prague observatory. He also collaborated with Maximilian → Hell and J. Lipský, who assisted him in finding map coordinates of Hungary and the determination of coordinates for some Hungarian cities and supported him in the field of higher mathematics. Z. often participated as the founder and editor of scientific journals: from 1788 to 1800 the newspaper "Allgemeinen geographischen Ephemeriden" in Weimar; in 1800 "Monatliche Correspondenz zur Beförderung der Erd- und Himmelskunde" at Gotha and from 1813 on in Geneva "Correspondance astronomique, géographique et hydrographique". These journals also published the results of his observations. One of the craters on the Moon is named after Z.
