Johann Kies
Who was Johann Kies?
German astronomer and mathematician
Biographical data adapted from Wikipedia’s article on Johann Kies (CC BY-SA 4.0).
Biography
Johann Kies (September 14, 1713 – July 29, 1781) was a German astronomer and mathematician born in Tübingen. His career covered several productive decades of 18th-century European astronomy. Kies was educated at the University of Tübingen and became well-known for his detailed observational work and spreading of Newtonian physics in the German-speaking world. He connected the practical needs of astronomical observation with the theories established by Isaac Newton and his followers in Europe.
From 1742 to 1754, Kies was recommended by the famous mathematician Leonhard Euler to be a professor of mathematics at Berlin's Academy of Sciences and an astronomer at its observatory. During this time, he wrote several significant reports. These included "De la Situation la plus avantageuse des planètes pour découvrir les irrégularités de leurs mouvemens," "Sur les Éclipses des étoiles fixes par la lune," and "Description d'un instrument qui se trouve à l'observatoire de Berlin." In his "Rapport de quelques observations célestes faites à l'observatoire Royal," he discussed the scientific importance of observing eclipses, highlighting their role in checking or correcting astronomical tables related to the Sun and Moon's movements.
In 1751, while in Berlin, Kies worked with the French astronomer Jérôme Lalande to study the lunar parallax, coordinating with Nicolas Louis de Lacaille's simultaneous measurements in the Cape of Good Hope. This was part of a larger international effort to measure the Moon's distance from Earth more accurately. From 1754 to 1755, Kies was the director of the Astronomisches Rechen-Institut in Heidelberg before returning to Tübingen to teach at the Collegium.
Kies was one of the first scholars to introduce and support Newton's theories of gravity in Germany. He focused two of his Latin works on Newton's findings: "De viribus centralibus," published in Tübingen in 1758, and "De lege gravitatis," published in Tübingen in 1773. He also wrote "De influxu lunae in partes terrae mobiles" in 1769, examining the Moon's effect on the Earth's moving parts. Throughout his career, he wrote extensively in both French and Latin, showing the international scholarly environment of his time.
Kies exchanged letters with Euler between 1747 and 1767, stemming from Euler's recommendation for his position in Berlin. All eight remaining letters in this correspondence were written by Kies, providing a glimpse into their intellectual exchange. Kies died in Tübingen on July 29, 1781, in the city where he had been born nearly sixty-eight years earlier.
Before Fame
Johann Kies was born on September 14, 1713, in Tübingen, a university town in the Duchy of Württemberg known for its academic life in Germany. He studied at the University of Tübingen, which was well-regarded in theology, philosophy, and the natural sciences. The early eighteenth century was a significant period for astronomy and mathematics in Europe, as the Newtonian system began to replace older Cartesian models, and observational astronomy became more systematic and internationally coordinated.
Kies honed his skills as German scientific institutions were developing, especially with the support of the Prussian Academy of Sciences in Berlin, revitalized under Frederick the Great. His growing reputation in mathematics and astronomy caught the attention of Leonhard Euler, a leading mathematician of the time. Euler's recommendation was crucial in Kies securing a prestigious position at the Berlin Academy. This was a turning point, transforming Kies from a scholar in training to a recognized figure in European scientific circles.
Key Achievements
- Appointed professor of mathematics at the Berlin Academy of Sciences and astronomer at its observatory from 1742 to 1754, on the recommendation of Leonhard Euler
- Participated in the internationally coordinated 1751 observations of lunar parallax alongside Jérôme Lalande in Berlin, concurrent with Lacaille's measurements at the Cape of Good Hope
- Served as director of the Astronomisches Rechen-Institut in Heidelberg from 1754 to 1755
- Authored De viribus centralibus and De lege gravitatis, two dedicated Latin treatises instrumental in spreading Newtonian gravitational theory in Germany
- Had the lunar crater Kies named in his honor, recognizing his contributions to selenographic and astronomical science
Did You Know?
- 01.The lunar crater Kies is named in his honor, preserving his name on the surface of the Moon he spent his career studying.
- 02.All eight surviving letters in the correspondence between Kies and Euler were written by Kies alone, meaning none of Euler's replies are known to have survived.
- 03.Kies coordinated his 1751 lunar parallax observations in Berlin with those of Lacaille at the Cape of Good Hope, one of the early examples of simultaneous multi-site astronomical measurement across continents.
- 04.He dedicated works published fifteen years apart, in 1758 and 1773, specifically to propagating Newton's gravitational theories, indicating a sustained personal commitment to spreading Newtonian science in Germany.
- 05.Kies wrote his scientific papers in both French and Latin rather than German, as was standard practice for scholars seeking a pan-European readership in the eighteenth century.