Eduard Schönfeld
Encyclopedia
Eduard Schönfeld was a German
astronomer
.
, in the Duchy of Saxe-Meiningen
, where he had a distinguished career at the gymnasium
. On leaving the gymnasium, he desired to devote himself to astronomy, but abandoned the idea in deference to his father's wishes. He went first to Hanover
, and afterwards to Kassel
to study architecture
, for which he seems to have had little inclination. 1849 found him studying chemistry
under Bunsen
at Marburg, where his love for astronomy was revived by Gerling
's lectures.
In 1851 he visited the Bonn Observatory and studied astronomy under Friedrich Wilhelm Argelander
. In 1853 he was appointed assistant, and in the following year won a doctor's degree with his treatise Nova elementa Thetidis. At Bonn he took an important part in preparing the Durchmusterung of the northern heavens. He took up the investigation of the light-changes in variable star
s, devoting to this work nights which, on account of moonlight
, were unsuitable for zone observations. The results of these researches were published in the Sitz. Berich. Wien. Akad. vol. xlii.
at Bonn, but in 1859 he was appointed director of the Mannheim Observatory
. The instrumental equipment of that observatory was somewhat antiquated, his largest telescope being a small refractor of 73 lines aperture
, but he selected a line of work to suit the instruments at his disposal, observing nebula
e and variable stars and keeping a watch on comet
s and new planet
s. The results of his observations of nebulae are contained in two catalogues published in the Astronomische Beobachtungen der Grossherzoglichen Sternwarte zu Mannheim, 1st and 2nd parts (1862 and 1875), and those of his variable star observations appeared in the Jahresberichte des Mannheimer Vereins für Naturkunde, Nos. 32 and 39 (1866 and 1875).
. The experience gained on the northern survey under Argelander's direction enabled Schönfeld to introduce some improvements in the methods employed, which increased the accuracy of this work, which was practically accomplished in March 1881, some revision only remaining to be done. These zone observations afforded 363,932 separate places of stars, and form the groundwork of the catalogue of 133,659 stars between 2 and 23 degrees south declination, which was published in 1886 as the eighth volume of the Bonn observations.
from its foundation in 1863, being a member of council up to 1869, and in 1875 becoming editor of its publications and secretary in conjunction with Winnecke
. In 1878 he was elected a Foreign Associate of the Royal Astronomical Society
.
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
astronomer
Astronomer
An astronomer is a scientist who studies celestial bodies such as planets, stars and galaxies.Historically, astronomy was more concerned with the classification and description of phenomena in the sky, while astrophysics attempted to explain these phenomena and the differences between them using...
.
Education
Schönfeld was born at HildburghausenHildburghausen
Hildburghausen is a town in Thuringia in central Germany, capital of the district Hildburghausen. It is situated on the river Werra, 20 km south of Suhl, and 25 km northwest of Coburg....
, in the Duchy of Saxe-Meiningen
Saxe-Meiningen
The Duchy of Saxe-Meiningen was one of the Saxon duchies held by the Ernestine line of the Wettin dynasty, located in the southwest of the present-day German state of Thuringia....
, where he had a distinguished career at the gymnasium
Gymnasium (school)
A gymnasium is a type of school providing secondary education in some parts of Europe, comparable to English grammar schools or sixth form colleges and U.S. college preparatory high schools. The word γυμνάσιον was used in Ancient Greece, meaning a locality for both physical and intellectual...
. On leaving the gymnasium, he desired to devote himself to astronomy, but abandoned the idea in deference to his father's wishes. He went first to Hanover
Hanover
Hanover or Hannover, on the river Leine, is the capital of the federal state of Lower Saxony , Germany and was once by personal union the family seat of the Hanoverian Kings of Great Britain, under their title as the dukes of Brunswick-Lüneburg...
, and afterwards to Kassel
University of Kassel
The University of Kassel, founded in 1970, is one of the newer universities in the state of Hesse. The university is in Kassel, and as of September 2010 has about 18,113 students...
to study architecture
Architecture
Architecture is both the process and product of planning, designing and construction. Architectural works, in the material form of buildings, are often perceived as cultural and political symbols and as works of art...
, for which he seems to have had little inclination. 1849 found him studying chemistry
Chemistry
Chemistry is the science of matter, especially its chemical reactions, but also its composition, structure and properties. Chemistry is concerned with atoms and their interactions with other atoms, and particularly with the properties of chemical bonds....
under Bunsen
Robert Bunsen
Robert Wilhelm Eberhard Bunsen was a German chemist. He investigated emission spectra of heated elements, and discovered caesium and rubidium with Gustav Kirchhoff. Bunsen developed several gas-analytical methods, was a pioneer in photochemistry, and did early work in the field of organoarsenic...
at Marburg, where his love for astronomy was revived by Gerling
Christian Ludwig Gerling
Christian Ludwig Gerling studied under Carl Friedrich Gauss, obtaining his doctorate in 1812 for a thesis entitled: Methodi proiectionis orthographicae usum ad calculos parallacticos facilitandos explicavit simulque eclipsin solarem die, at the University of Göttingen...
's lectures.
In 1851 he visited the Bonn Observatory and studied astronomy under Friedrich Wilhelm Argelander
Friedrich Wilhelm Argelander
Friedrich Wilhelm August Argelander was a German astronomer. He is known for his determinations of stellar brightnesses, positions, and distances.- Life and work :...
. In 1853 he was appointed assistant, and in the following year won a doctor's degree with his treatise Nova elementa Thetidis. At Bonn he took an important part in preparing the Durchmusterung of the northern heavens. He took up the investigation of the light-changes in 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, devoting to this work nights which, on account of moonlight
Moonlight
Moonlight is the light that reaches Earth from the Moon. This light does not originate from the Moon, but from sunlight. The Moon does not, however, reflect sunlight like a mirror, but it reflects light from those portions of its surface which the Sun's light strikes. See diffuse reflection.In...
, were unsuitable for zone observations. The results of these researches were published in the Sitz. Berich. Wien. Akad. vol. xlii.
Mannheim Observatory
For a short time he was a PrivatdozentPrivatdozent
Privatdozent or Private lecturer is a title conferred in some European university systems, especially in German-speaking countries, for someone who pursues an academic career and holds all formal qualifications to become a tenured university professor...
at Bonn, but in 1859 he was appointed director of the Mannheim Observatory
Mannheim Observatory
The Mannheim Observatory was a tower observatory built between 1772 and 1774 in Mannheim, Germany, which remained in operation until 1880. The observatory was transferred to Karlsruhe and finally in 1898, was established on the Königstuhl near Heidelberg where today’s successor institution thr...
. The instrumental equipment of that observatory was somewhat antiquated, his largest telescope being a small refractor of 73 lines aperture
Aperture
In optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture of an optical system is the opening that determines the cone angle of a bundle of rays that come to a focus in the image plane. The aperture determines how collimated the admitted rays are,...
, but he selected a line of work to suit the instruments at his disposal, observing nebula
Nebula
A nebula is an interstellar cloud of dust, hydrogen gas, helium gas and other ionized gases...
e and variable stars and keeping a watch on comet
Comet
A comet is an icy small Solar System body that, when close enough to the Sun, displays a visible coma and sometimes also a tail. These phenomena are both due to the effects of solar radiation and the solar wind upon the nucleus of the comet...
s and new planet
Planet
A planet is a celestial body orbiting a star or stellar remnant that is massive enough to be rounded by its own gravity, is not massive enough to cause thermonuclear fusion, and has cleared its neighbouring region of planetesimals.The term planet is ancient, with ties to history, science,...
s. The results of his observations of nebulae are contained in two catalogues published in the Astronomische Beobachtungen der Grossherzoglichen Sternwarte zu Mannheim, 1st and 2nd parts (1862 and 1875), and those of his variable star observations appeared in the Jahresberichte des Mannheimer Vereins für Naturkunde, Nos. 32 and 39 (1866 and 1875).
Bonn Observatory
On the death of Argelander, which occurred on February 17, 1875, Schönfeld was appointed to succeed him as director of the Bonn Observatory, and soon after his appointment he began his last and greatest piece of work, the extension, on Argelander's plan, of the survey of the heavens down to 23 degrees of south declinationDeclination
In astronomy, declination is one of the two coordinates of the equatorial coordinate system, the other being either right ascension or hour angle. Declination in astronomy is comparable to geographic latitude, but projected onto the celestial sphere. Declination is measured in degrees north and...
. The experience gained on the northern survey under Argelander's direction enabled Schönfeld to introduce some improvements in the methods employed, which increased the accuracy of this work, which was practically accomplished in March 1881, some revision only remaining to be done. These zone observations afforded 363,932 separate places of stars, and form the groundwork of the catalogue of 133,659 stars between 2 and 23 degrees south declination, which was published in 1886 as the eighth volume of the Bonn observations.
Affiliations
Schönfeld was a member of the Astronomische GesellschaftAstronomische Gesellschaft
The Astronomische Gesellschaft is an astronomical society established in 1863 in Heidelberg, the second oldest astronomical society after the Royal Astronomical Society....
from its foundation in 1863, being a member of council up to 1869, and in 1875 becoming editor of its publications and secretary in conjunction with Winnecke
Friedrich August Theodor Winnecke
Friedrich August Theodor Winnecke was a German astronomer.He worked at Pulkovo Observatory from 1858 to 1865, but returned to Germany and served as professor of astronomy at Strasbourg from 1872 to 1881.He discovered or co-discovered a large number of comets, including the periodic comet...
. In 1878 he was elected a Foreign Associate of the Royal Astronomical Society
Royal Astronomical Society
The Royal Astronomical Society is a learned society that began as the Astronomical Society of London in 1820 to support astronomical research . It became the Royal Astronomical Society in 1831 on receiving its Royal Charter from William IV...
.