Gustav Müller
Encyclopedia
Karl Hermann Gustav Müller (May 7, 1851–July 7, 1925) was a German astronomer.
He was born in Schweidnitz
, Silesia
to a merchant father; his father died
when Gustav was six. In 1870 he entered the University of Leipzig
, then transferred to the University of Berlin two years later. He was awarded a Ph.D. in 1877 with a thesis on the subject of micrometer
screws. Thereupon he became an assistant at the Astrophysical Observatory of Potsdam. His primary career focus became the spectrum of the Sun and celestial photometry.
Between 1880–82, he assisted Hermann Carl Vogel
in building a catalog of stellar spectra. In 1877 he began making photometric observations of the planets and their atmospheres. He led the German expedition to Hartford, Connecticut
to observe the transit of Venus
in 1882. In 1886 he began a collaboration with Paul Kempf to assemble the Potsdam Durchmunsterung, which was a stellar catalogue of all stars in the northern hemisphere with a magnitude of 7.5 or brighter. In 1897 he published the manual Die Photometrie der Gestirne (The Photometry of Stars). Between 1900 and 1915, he and Hartwig produced a three volume catalogue of 1,687 variable star
s.
Between 1896 and 1924, he served as a secretary of the Astronomische Gesellschaft
. In 1918 he was elected to the Prussian Academy of Sciences
. From 1917–1921 he was the director of the Astrophysical Observatory at Potsdam. Due to legal requirements, he retired in 1921 at the age of seventy. He was married three times and had seven children. One son was killed during World War I
and a second in the aftermath. His son Rolf became an astronomer at the Potsdam Observatory.
He was born in Schweidnitz
Swidnica
Świdnica is a city in south-western Poland in the region of Silesia. It has a population of 60,317 according to 2006 figures. It lies in Lower Silesian Voivodeship, being the seventh largest town in that voivodeship. From 1975–98 it was in the former Wałbrzych Voivodeship...
, Silesia
Silesia
Silesia is a historical region of Central Europe located mostly in Poland, with smaller parts also in the Czech Republic, and Germany.Silesia is rich in mineral and natural resources, and includes several important industrial areas. Silesia's largest city and historical capital is Wrocław...
to a merchant father; his father died
when Gustav was six. In 1870 he entered the University of Leipzig
University of Leipzig
The University of Leipzig , located in Leipzig in the Free State of Saxony, Germany, is one of the oldest universities in the world and the second-oldest university in Germany...
, then transferred to the University of Berlin two years later. He was awarded a Ph.D. in 1877 with a thesis on the subject of micrometer
Micrometer
A micrometer , sometimes known as a micrometer screw gauge, is a device incorporating a calibrated screw used widely for precise measurement of small distances in mechanical engineering and machining as well as most mechanical trades, along with other metrological instruments such as dial, vernier,...
screws. Thereupon he became an assistant at the Astrophysical Observatory of Potsdam. His primary career focus became the spectrum of the Sun and celestial photometry.
Between 1880–82, he assisted Hermann Carl Vogel
Hermann Carl Vogel
Hermann Carl Vogel was a German astronomer. He was born in Leipzig, Kingdom of Saxony.Vogel pioneered the use of the spectroscope in astronomy...
in building a catalog of stellar spectra. In 1877 he began making photometric observations of the planets and their atmospheres. He led the German expedition to Hartford, Connecticut
Hartford, Connecticut
Hartford is the capital of the U.S. state of Connecticut. The seat of Hartford County until Connecticut disbanded county government in 1960, it is the second most populous city on New England's largest river, the Connecticut River. As of the 2010 Census, Hartford's population was 124,775, making...
to observe the transit of Venus
Transit of Venus
A transit of Venus across the Sun takes place when the planet Venus passes directly between the Sun and Earth, becoming visible against the solar disk. During a transit, Venus can be seen from Earth as a small black disk moving across the face of the Sun...
in 1882. In 1886 he began a collaboration with Paul Kempf to assemble the Potsdam Durchmunsterung, which was a stellar catalogue of all stars in the northern hemisphere with a magnitude of 7.5 or brighter. In 1897 he published the manual Die Photometrie der Gestirne (The Photometry of Stars). Between 1900 and 1915, he and Hartwig produced a three volume catalogue of 1,687 variable star
Variable star
A star is classified as variable if its apparent magnitude as seen from Earth changes over time, whether the changes are due to variations in the star's actual luminosity, or to variations in the amount of the star's light that is blocked from reaching Earth...
s.
Between 1896 and 1924, he served as a secretary of the Astronomische Gesellschaft
Astronomische Gesellschaft
The Astronomische Gesellschaft is an astronomical society established in 1863 in Heidelberg, the second oldest astronomical society after the Royal Astronomical Society....
. In 1918 he was elected to the Prussian Academy of Sciences
Prussian Academy of Sciences
The Prussian Academy of Sciences was an academy established in Berlin on 11 July 1700, four years after the Akademie der Künste or "Arts Academy", to which "Berlin Academy" may also refer.-Origins:...
. From 1917–1921 he was the director of the Astrophysical Observatory at Potsdam. Due to legal requirements, he retired in 1921 at the age of seventy. He was married three times and had seven children. One son was killed during World War I
World War I
World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...
and a second in the aftermath. His son Rolf became an astronomer at the Potsdam Observatory.