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35-720: The earliest precursor of today's GDCh was the German Chemical Society ( Deutsche Chemische Gesellschaft zu Berlin , DChG). Adolf von Baeyer was prominent among the German chemists who established DChG in 1867; and August Wilhelm von Hofmann was the first president. This society was modeled after the British Chemical Society , which was the precursor of the Royal Society of Chemistry . Like its British counterpart, DChG sought to foster

70-419: A meridian circle from Reichenbach , assisted by some of his qualified students. The most prominent of them was Friedrich Wilhelm Argelander , his successors were Otto August Rosenberger and August Ludwig Busch . Bessel determined the first reliable value for the distance between a star and the solar system with a heliometer from Fraunhofer using the method of stellar parallax . In 1838 he published

105-766: A chunk of indigo worth two Thalers for his first dye experiments. When a schoolboy, his chemistry teacher at the Friedrich Wilhelm Gymnasium appointed him as his assistant. After graduating from secondary school in 1853, he entered the Berlin University to study physics and mathematics. A stint in the Prussian army interrupted his study until 1856, when he returned to academia at the University of Heidelberg , intending to study chemistry under Robert Bunsen . After an argument with

140-403: A lasting impact upon the work of Neumann's students and upon the Prussian conception of precision in measurement. Bessel had two sons and three daughters. His elder son became an architect but died suddenly in 1840 aged 26; his younger son died shortly after birth. His eldest daughter, Marie, married the physicist Georg Adolf Erman , member of the scholar family Erman . One of their sons in turn

175-554: A member of ChemPubSoc Europe , which is an organization of 16 European chemical societies. This European consortium was established in the late 1990s as many chemical journals owned by national chemical societies were amalgamated. The society acknowledges individual achievement with prizes and awards, including medals originally conferred by the predecessor organizations DChG and VDCh: Adolf von Baeyer Johann Friedrich Wilhelm Adolf von Baeyer ( German: [ˈaːdɔlf fɔn ˈbaɪɐ] ; 31 October 1835 – 20 August 1917)

210-419: A parallax of 0.314 arcseconds for 61 Cygni , which indicated that the star is 10.3 ly away. Compared with the current measurement of 11.4 ly, Bessel's figure had an error of 9.6%. Thanks to these results astronomers had not only enlarged the vision of the universe well beyond the cosmic magnitude, but after the discovery in 1728 by James Bradley of the aberration of light a second empirical evidence of

245-436: A professor at the University of Strasbourg in 1871. In 1875, he succeeded Justus von Liebig as Chemistry Professor at the University of Munich . Baeyer's chief achievements include the synthesis and description of the plant dye indigo , the discovery of the phthalein dyes, and the investigation of polyacetylenes , oxonium salts , nitroso compounds (1869) and uric acid derivatives (1860 and onwards) (including

280-655: A report on astronomical clocks. Bessel married Johanna Hagen, the daughter of the chemist and pharmacist Karl Gottfried Hagen who was the uncle of the physician and biologist Hermann August Hagen and the hydraulic engineer Gotthilf Hagen , the latter also Bessel's student and assistant from 1816 to 1818. The physicist Franz Ernst Neumann , Bessel's close companion and colleague, was married to Johanna Hagen's sister Florentine. Neumann introduced Bessel's exacting methods of measurement and data reduction into his mathematico-physical seminar, which he co-directed with Carl Gustav Jacob Jacobi at Königsberg. These exacting methods had

315-875: A way of determining longitude . Bessel came to the attention of Heinrich Wilhelm Olbers , a practising physician of Bremen and well-known astronomer, by producing a refinement on the orbital calculations for Halley's Comet in 1804, using old observation data taken from Thomas Harriot and Nathaniel Torporley in 1607. Franz Xaver von Zach edited the results in his journal Monatliche Correspondenz . Having finished his commercial education, Bessel left Kulenkamp in 1806 and became assistant at Johann Hieronymus Schröter 's private observatory in Lilienthal near Bremen as successor of Karl Ludwig Harding . There he worked on James Bradley 's stellar observation data to produce precise positions for some 3,222 stars. Despite lacking any higher education, especially at university, Bessel

350-402: A young age while she was giving birth to his sister Adelaide. Although his birth name was Johann Friedrich Wilhelm Adolf Baeyer, he was known simply as Adolf throughout most of his life. The poet Adelbert von Chamisso and the astronomer Friedrich Wilhelm Bessel were his godparents. On his 50th birthday he was raised to the hereditary nobility by King Ludwig II of Bavaria , conferring on him

385-601: Is also the Von Baeyer nomenclature in structural chemistry and Baeyer strain theory (which granted him the Nobel prize) of alicyclic compounds . In 2009 von Baeyer lunar crater was named after him. In 1868, Baeyer married Adelheid (Lida) Bendemann, the daughter of a family friend, and together the couple had three children: Eugenie, Hans, and Otto  [ de ] . He died on 20 August 1917 in Starnberg at

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420-658: The University of Göttingen in March 1811. Both scientists were in correspondence from 1804 to 1843. In 1837 they got in quarrel about Gauss's habit of very slow publication. In 1842 Bessel took part in the annual meeting of the British Association for the Advancement of Science in Manchester, accompanied by the geophysicist Georg Adolf Erman and the mathematician Carl Gustav Jacob Jacobi , where he gave

455-402: The "von" distinction. Baeyer became interested in science early, performing experiments on plant nutrition at his paternal grandfather's Müggelsheim farm as a boy. In Berlin he began chemical experimentation at the age of nine. Three years later, he synthesized a previously unknown chemical compound -double carbonate of copper and sodium. On his 13th birthday, he initiated his lifework, buying

490-507: The Earth's relative movement was produced. A short time later Friedrich Georg Wilhelm Struve and Thomas Henderson reported the parallaxes of Vega and Alpha Centauri . Precise measurements with a new meridian circle from Adolf Repsold allowed Bessel to notice deviations in the motions of Sirius and Procyon , which must be caused by the gravitational attraction of unseen companions. His announcement of Sirius's "dark companion" in 1844

525-665: The Moon's Mare Serenitatis . The main-belt asteroid 1552 Bessel was named at the centenary of the parallaxe determination in 1938. Geographical commemorations are two fjords in Greenland, Bessel Fjord, NE Greenland and Bessel Fjord, NW Greenland . Xyletinus besseli a fossil beetle from the Eocene belonging to the family Ptinidae , found in the Baltic amber in Sambia ,

560-567: The Prussian army; the final report was published in 1838. He also obtained an estimate of increased accuracy for the Earth's ellipsoid , nowadays called the Bessel ellipsoid , based on several arc measurements . Bessel was one of the first members of the Order Pour le Merite (Civil class) when it was established in 1842. The first cosmic object named after Bessel is the largest crater in

595-547: The age of 81. Friedrich Bessel Friedrich Wilhelm Bessel ( German: [ˈbɛsl̩] ; 22 July 1784 – 17 March 1846) was a German astronomer , mathematician , physicist , and geodesist . He was the first astronomer who determined reliable values for the distance from the sun to another star by the method of parallax . Certain important mathematical functions were named Bessel functions after Bessel's death, though they had originally been discovered by Daniel Bernoulli before being generalised by Bessel. Bessel

630-490: The chemical industry, through his work on organic dyes and hydroaromatic compounds", and he continued in full active work as one of the best-known teachers in the world of organic chemistry up to within a year of his death. The Adolf von Baeyer Medal  [ de ] has been awarded annually since 1911. His name is reflected in various "name reactions" as the Baeyer–Villiger oxidation and Baeyer's reagent . There

665-625: The communication of new ideas and facts throughout Germany and across international borders. In 1946, the current organization was created by a merger of the German Chemical Society (DChG) and the Association of German Chemists ( Verein Deutscher Chemiker , VDCh). Honorary Members of the GDCh have included Otto Hahn , Robert B. Woodward , Jean-Marie Lehn , George Olah and other eminent scientists. Scientific publications of

700-531: The discovery of barbituric acid (1864), the parent compound of the barbiturates ). He was the first to propose the correct formula for indole in 1869, after publishing the first synthesis three years earlier. His contributions to theoretical chemistry include the 'strain' ( Spannung ) theory of triple bonds and strain theory in small carbon rings. In 1871 he discovered the synthesis of phenolphthalein by condensation of phthalic anhydride with two equivalents of phenol under acidic conditions (hence

735-413: The formula for the sample variance estimator is named in his honour. This is the use of the factor n  − 1 in the denominator of the formula, rather than just n . This occurs when the sample mean rather than the population mean is used to centre the data and since the sample mean is a linear combination of the data the residual to the sample mean overcounts the number of degrees of freedom by

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770-487: The name). That same year he was the first to obtain synthetic fluorescein , a fluorophore pigment which is similar to naturally occurring pyoverdin that is synthesised by microorganisms (e.g., by some fluorescent strains of Pseudomonas ). Baeyer named his finding "resorcinphthalein" as he had synthesised it from phthalic anhydride and resorcinol . The term fluorescein would not start to be used until 1878. In 1872 he experimented with phenol and formaldehyde ;

805-469: The number of constraint equations — in this case one. Like numerous astronomers of his time Bessel dealt on the field of geodesy , too, first theoretically, when he published a method for solving the main geodetic problem . In 1830 he got the royal order for the survey of East Prussia with the purpose to connect the yet existing Prussian and Russian triangulation networks . This work was carried out in cooperation with Johann Jacob Baeyer , then major of

840-600: The observatory was still in construction Bessel elaborated the Fundamenta Astronomiae based on Bradley's observations. As a preliminary result he produced tables of atmospheric refraction that won him the Lalande Prize from the French Academy of Sciences in 1811. The Königsberg Observatory began operation in 1813. Starting in 1819, Bessel determined the position of over 50,000 stars with

875-539: The position calculated by Le Verrier in September 1846 at Berlin Observatory . In the second decade of the 19th century, while studying the dynamics gravitational systems as multi-body problem , Bessel developed what are now known as Bessel functions . Critical for the solution of certain differential equations , these functions are used throughout both classical and quantum physics . A correction term in

910-535: The renowned chemist he changed his mentor to August Kekulé . He continued to collaborate with Kekulé even after he returned to Berlin in 1858 for the completion of his doctorate on arsenic methyl chloride, or cacodylic chloride . After completing his doctorate, he followed Kekulé to the University of Ghent , when Kekulé became professor there. He became a lecturer at the Gewerbeinstitut Berlin  [ de ] (Royal Trade Academy) in 1860 and

945-664: The resinous product was a precursor for Leo Baekeland 's later commercialization of Bakelite . In 1881 the Royal Society of London awarded Baeyer the Davy Medal for his work with indigo. He was elected a Foreign Honorary Member of the American Academy of Arts and Sciences in 1884. In 1905 he was awarded the Nobel Prize in Chemistry "in recognition of his services in the advancement of organic chemistry and

980-412: The society include Nachrichten aus der Chemie , Angewandte Chemie , Chemistry: A European Journal , European Journal of Inorganic Chemistry , European Journal of Organic Chemistry , ChemPhysChem , ChemSusChem , ChemBioChem , ChemMedChem , ChemCatChem , ChemistryViews , Chemie Ingenieur Technik and Chemie in unserer Zeit . In the 21st century, the society has become

1015-533: The time of his birth and he was raised in the Lutheran religion. His mother was the daughter of Julius Eduard Hitzig and a member of the originally Jewish Itzig family , and had converted to Christianity before marrying his father, who was of non-Jewish German descent. Baeyer had four sisters: Clara (born 1826) Emma (born 1831), Johanna (Jeanette) (born 1839), Adelaide (died 1843) and two brothers: Georg (born 1829) and Edward (born 1832). Baeyer lost his mother at

1050-819: The transit time of stars. In 1824, Bessel developed a new method for calculating the circumstances of eclipses using the so-called Besselian elements . His method simplified the calculation to such an extent, without sacrificing accuracy, that it is still in use today. On Bessel's proposal the Prussian Academy of Sciences started the edition of the Berliner Akademische Sternkarten ( Berlin Academic Star Charts ) in 1825 as an international project with Johann Franz Encke as executive editor. One unpublished new chart enabled Johann Gottfried Galle to find Neptune near

1085-778: Was a German chemist who synthesised indigo and developed a nomenclature for cyclic compounds (that was subsequently extended and adopted as part of the IUPAC organic nomenclature ). He was ennobled in the Kingdom of Bavaria in 1885 and was the 1905 recipient of the Nobel Prize in Chemistry . Baeyer was born in Berlin as the son of the noted geodesist and captain of the Royal Prussian Army Johann Jacob Baeyer and his wife Eugenie Baeyer née Hitzig (1807–1843). Both his parents were Lutherans at

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1120-562: Was appointed director of the newly founded Königsberg Observatory by King Frederick William III of Prussia in January 1810, at the age of 25, and remained in that position until his death. Some elder professors of the Philosophical Faculty disputed Bessel's right to teach mathematics without any academic degree. Therefore, he turned to his fellow Carl Friedrich Gauss , who provided the award of an honorary doctor degree from

1155-587: Was born in Minden , Westphalia , then capital of the Prussian administrative region Minden-Ravensberg , as second son of a civil servant into a large family. At the age of 14 he left the school, because he did not like the education in Latin language, and apprenticed in the import-export concern Kulenkamp at Bremen . The business's reliance on cargo ships led him to turn his mathematical skills to problems in navigation . This in turn led to an interest in astronomy as

1190-525: Was the first correct claim of a previously unobserved companion by positional measurement, and eventually led to the discovery of Sirius B by Alvan Graham Clark in 1862, the first discovery of a white dwarf . John Martin Schaeberle discovered Procyon B in 1896. Bessel was the first scientist who realized the effect later called personal equation , that several simultaneously observing persons determine slightly different values, especially recording

1225-459: Was the renowned Egyptologist Adolf Erman . His third daughter Johanna married the politician Adolf Hermann Hagen ; one of their sons was the physicist Ernst Bessel Hagen , and the mathematician Erich Bessel-Hagen was a grandson of them. Bessel was godfather of Adolf von Baeyer , son of his collaborator Johann Jacob Baeyer . After several months of illness Bessel died in March 1846 at his observatory from retroperitoneal fibrosis . While

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