### Astronomy Bio...Karl Friedrich Gauss

#### Jay Bitterman

Karl, Friedrich Gauss** **was born in Braunschweig (Brunswick), Germany on April 30, 1777, to a very poor, uneducated family. His father worked as a gardener, a merchant's assistant and the treasurer of an insurance fund. At the age of three Gauss taught himself to count and read. He is said to have spotted a mistake in his father's arithmetic. At the age of eight, in elementary school, he could add the first 100 digits for his first lesson. His teacher recognized his precocious talent and convinced his father that the boy should pursue a profession rather than a trade. At the age of eleven, in high school, he exhibited proficiency in both the classics and mathematics. When he was fourteen he was presented at the Duke of Brunswick's court to display his skill at computing. The Duke was so impressed that he gave the teenager a life time grant that continued until his own death in 1806. In 1792, with the Duke's aid, Gauss began to study at the Collegium Carolinum in Brunswick. Between the ages of fourteen and seventeen, Gauss devised many theories and mathematical proofs, but because of his lack of experience in publication and his diffidence, he had to be rediscovered in the following decades. The extent to which this was true was revealed only after Gauss's death. There are, however, various innovations that are attributed directly to him during his three years at the Collegium Carolinum. They include the principle of least squares (by which the equation curve best fitting a set of observations can be drawn).

In 1795, having completed some significant work on quadratic residues, Gauss began to study at the University of Göttingen, where he had access to the works of Fermat, Euler, Lagrange and Legendre. He immediately seized the opportunity to write a book on the theory of numbers, which appeared in 1801 as "Disquisitiones Arithmeticae",* *generally regarded to be his greatest accomplishment. In it, he summarized all the work which had been carried out up to that time and formulated concepts and questions that are still relevant today. From 1795 to 1798 he studied at the University of Göttingen. In 1799 he earned a doctorate from the University of Helmstedt. By this time he nearly completed all his fundamental mathematical discoveries.

In 1801 he decided to satisfy his interest in astronomy, and by 1807 he pursued it so enthusiastically that he became the director of the Göttingen Observatory while a professor of mathematics. During this time, he also gained recognition around the world; he was offered a position in St. Petersburg, as a foreign member of the Royal Society in London. Additionally he was invited to join the Russian and French Academies of Sciences. Nevertheless, Gauss decided to remain at Göttingen for the rest of his life.

From 1800 to 1810 Gauss concentrated on mathematical applications for astronomy. In astronomy he corresponded with his friend Alexander Von Humboldt (1769-1859) who played an important part in the development of science in Germany. With the discovery of the first asteroid, Ceres, at the beginning of 1801 by Guiseppe Piazzi (1746-1826) Gauss had an opportunity to use his mathematical brilliance. In 1809 he developed a quick method for calculating the asteroid's orbit from only three observations and published his classic astronomical work. The 1,001^{st} planetoid to be discovered was named Gauss in his honor. He also worked out the theories of perturbations that were eventually used by Le Verrier and Adams in their independent calculations that led to the discovery of Neptune. After 1817 he did no further work in theoretical astronomy, although he continued to work in positional astronomy for the rest of his life.

Gauss also pioneered in topology, crystallography, optics, mechanics and capillarity. At Göttingen he devised the heliotrope, a type of heliostat that has applications in surveying. After 1831 he collaborated with Wilhelm Weber (1804-1891) on research into electricity and magnetism and in 1833 they invented an electromagnetic telegraph. Gauss devised logical sets of units for magnetic phenomena; a unit of magnetic flux density is therefore named after him. There is scarcely any physical, mathematical or astronomical field in which Gauss did not work. His innovations in mathematics alone proved him to be the equal of Archimedes and Newton. He was also an accomplished linguist and taught himself Russian.

He retained an active mind well into old age and on February 23, 1855 at the age of 62 he died. The full value of his work has been realized only in the twentieth century.

Published in the April 2000 issue of the NightTimes