Hermann Struve
Encyclopedia
Karl Hermann Struve was a Russian
Russian Empire
The Russian Empire was a state that existed from 1721 until the Russian Revolution of 1917. It was the successor to the Tsardom of Russia and the predecessor of the Soviet Union...

 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...

. In Russian
Russian language
Russian is a Slavic language used primarily in Russia, Belarus, Uzbekistan, Kazakhstan, Tajikistan and Kyrgyzstan. It is an unofficial but widely spoken language in Ukraine, Moldova, Latvia, Turkmenistan and Estonia and, to a lesser extent, the other countries that were once constituent republics...

, his name is sometimes given as German Ottovich Struve (Герман Оттович Струве) or German Ottonovich Struve (Герман Оттонович Струве).

Herman Struve was a part of the famous group of astronomers from the Struve family
Struve family
The Struve family were a dynasty of five generations of astronomers from the 18th to 20th centuries. Members of the family were also prominent in chemistry, government and diplomacy.-Origins:...

, which also included his grandfather Friedrich Georg Wilhelm von Struve
Friedrich Georg Wilhelm von Struve
Friedrich Georg Wilhelm von Struve was a Danish-Baltic German astronomer from a famous dynasty.-Life:...

, father Otto Wilhelm von Struve
Otto Wilhelm von Struve
Otto Wilhelm von Struve was a Russian astronomer. In Russian, his name is normally given as Otto Vasil'evich Struve...

, brother Ludwig Struve
Ludwig Struve
Gustav Wilhelm Ludwig Struve was a Russian astronomer, part of the famous Baltic German Struve family. In Russian, his name is sometimes given as Lyudvig Ottovich Struve or Lyudvig Ottonovich Struve .-Biography:Gustav Wilhelm Ludwig Struve was born in 1858 in Tsarskoye Selo – a former...

 and nephew Otto Struve
Otto Struve
Otto Struve was a Russian astronomer. In Russian, his name is sometimes given as Otto Lyudvigovich Struve ; however, he spent most of his life and his entire scientific career in the United States...

. Unlike other astronomers of the Struve family, Herman spent most of his career in Germany
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...

. Continuing the family tradition, Struve's research was focused on determining position of stellar object. He was particular known for his work on satellites of planets of the Solar System
Solar System
The Solar System consists of the Sun and the astronomical objects gravitationally bound in orbit around it, all of which formed from the collapse of a giant molecular cloud approximately 4.6 billion years ago. The vast majority of the system's mass is in the Sun...

 and development of the intersatellite method of correcting their orbital position. The mathematical Struve function is named after him.

Biography

Herman was born in 1854 in Tsarskoye Selo
Tsarskoye Selo
Tsarskoye Selo is the town containing a former Russian residence of the imperial family and visiting nobility, located south from the center of St. Petersburg. It is now part of the town of Pushkin and of the World Heritage Site Saint Petersburg and Related Groups of Monuments.-History:In...

 – a former Russian
Russian Empire
The Russian Empire was a state that existed from 1721 until the Russian Revolution of 1917. It was the successor to the Tsardom of Russia and the predecessor of the Soviet Union...

 residence of the imperial family
Romanov
The House of Romanov was the second and last imperial dynasty to rule over Russia, reigning from 1613 until the February Revolution abolished the crown in 1917...

 and visiting nobility, located 26 kilometres (16.2 mi) south from the center of St. Petersburg
Saint Petersburg
Saint Petersburg is a city and a federal subject of Russia located on the Neva River at the head of the Gulf of Finland on the Baltic Sea...

. He attended gymnasium in Vyborg
Vyborg
Vyborg is a town in Leningrad Oblast, Russia, situated on the Karelian Isthmus near the head of the Bay of Vyborg, to the northwest of St. Petersburg and south from Russia's border with Finland, where the Saimaa Canal enters the Gulf of Finland...

 and in 1872 entered the Tartu University (Tartu
Tartu
Tartu is the second largest city of Estonia. In contrast to Estonia's political and financial capital Tallinn, Tartu is often considered the intellectual and cultural hub, especially since it is home to Estonia's oldest and most renowned university. Situated 186 km southeast of Tallinn, the...

 was known then as Dorpat). While studying there, in 1874–1875, Struve participated in an expedition to observe transit of Venus through the disk of the Sun. That observation was carried out at Port Poisset on the Asiatic East Coast. After graduation in 1877, he became member of the Pulkovo Observatory
Pulkovo Observatory
The Pulkovo Astronomical Observatory астрономи́ческая обсервато́рия Росси́йской акаде́мии нау́к), the principal astronomical observatory of the Russian Academy of Sciences, located 19 km south of Saint Petersburg on Pulkovo Heights...

 and was sent abroad for two-year post-graduate studies. Accompanied by his cousin's husband, Struve stayed in several cities, including Strasbourg
Strasbourg
Strasbourg is the capital and principal city of the Alsace region in eastern France and is the official seat of the European Parliament. Located close to the border with Germany, it is the capital of the Bas-Rhin département. The city and the region of Alsace are historically German-speaking,...

, Paris
Paris
Paris is the capital and largest city in France, situated on the river Seine, in northern France, at the heart of the Île-de-France region...

, Milan
Milan
Milan is the second-largest city in Italy and the capital city of the region of Lombardy and of the province of Milan. The city proper has a population of about 1.3 million, while its urban area, roughly coinciding with its administrative province and the bordering Province of Monza and Brianza ,...

, Graz
Graz
The more recent population figures do not give the whole picture as only people with principal residence status are counted and people with secondary residence status are not. Most of the people with secondary residence status in Graz are students...

 and Berlin
Berlin
Berlin is the capital city of Germany and is one of the 16 states of Germany. With a population of 3.45 million people, Berlin is Germany's largest city. It is the second most populous city proper and the seventh most populous urban area in the European Union...

, learning from such celebrities as Helmholtz
Hermann von Helmholtz
Hermann Ludwig Ferdinand von Helmholtz was a German physician and physicist who made significant contributions to several widely varied areas of modern science...

, Kirchhoff
Gustav Kirchhoff
Gustav Robert Kirchhoff was a German physicist who contributed to the fundamental understanding of electrical circuits, spectroscopy, and the emission of black-body radiation by heated objects...

, Boltzmann
Ludwig Boltzmann
Ludwig Eduard Boltzmann was an Austrian physicist famous for his founding contributions in the fields of statistical mechanics and statistical thermodynamics...

 and Weierstrass
Karl Weierstrass
Karl Theodor Wilhelm Weierstrass was a German mathematician who is often cited as the "father of modern analysis".- Biography :Weierstrass was born in Ostenfelde, part of Ennigerloh, Province of Westphalia....

. After returning to Russia, he joined the staff of Pulkovo Observatory
Pulkovo Observatory
The Pulkovo Astronomical Observatory астрономи́ческая обсервато́рия Росси́йской акаде́мии нау́к), the principal astronomical observatory of the Russian Academy of Sciences, located 19 km south of Saint Petersburg on Pulkovo Heights...

, studying the satellites
Natural satellite
A natural satellite or moon is a celestial body that orbits a planet or smaller body, which is called its primary. The two terms are used synonymously for non-artificial satellites of planets, of dwarf planets, and of minor planets....

 of Saturn
Saturn
Saturn is the sixth planet from the Sun and the second largest planet in the Solar System, after Jupiter. Saturn is named after the Roman god Saturn, equated to the Greek Cronus , the Babylonian Ninurta and the Hindu Shani. Saturn's astronomical symbol represents the Roman god's sickle.Saturn,...

 among other things.

In 1881, Struve obtained his master degree at the University of Tartu, with the highest honors, and in 1882 defended a PhD thesis at Saint Petersburg University
Saint Petersburg State University
Saint Petersburg State University is a Russian federal state-owned higher education institution based in Saint Petersburg and one of the oldest and largest universities in Russia....

 (Pulkovo had no associated educational institutions). Both works were in the field of optics, in particular, the master thesis was titled "On Fresnel interference phenomenon – theoretical and experimental work" – according to Struve himself, despite the family traditions, he did not intend then to become an astronomer. However later, he got excited with his father's project of building an 30-inch telescope at Pulkovo and with the fantastic new possibilities for observation. Struve used that telescope a lot during his work. In 1883, he was appointed adjunct astronomer at Pulkovo Observatory.

By then, Struve family was highly respected in Russia and Tsar Alexander III
Alexander III of Russia
Alexander Alexandrovich Romanov , historically remembered as Alexander III or Alexander the Peacemaker reigned as Emperor of Russia from until his death on .-Disposition:...

 had a strong wish for Hermann to succeed his father Otto as the director of the Pulkovo Observatory. However, Hermann politely declined the offer mentioning that he was in the middle of crucial observations of Saturn which would be interrupted by administrative tasks. In 1890, Struve was appointed as the senior astronomer at Pulkovo with the clear understanding that he should become director after completing his Saturn work. However, the death of Alexander III in 1894 freed Struve from this task. The pro-Russian views were gradually developing in the Russian society, including science, and foreigners felt progressively more alienated. Therefore, when in 1895 Struve was offered position of professor at Königsberg University, he gladly accepted and moved his family to Germany. There, he succeeded W. Foerster as director of Königsberg Observatory. Struve was also called for the task of rescuing the Berlin Observatory. It was then located in the center of Berlin where astronomy observations were not practical and rents were too high, and discussions of its relocation stalled. Struve managed to sell the old observatory site so profitably that he could build a new observatory from scratch. The location was chosen at Neubabelsberg
Potsdam-Babelsberg
Babelsberg is the largest district of the Brandenburg capital Potsdam in Germany. The affluent neighbourhood named after a small hill on the Havel river is famous for Babelsberg Palace and Park, part of the Palaces and Parks of Potsdam and Berlin UNESCO World Heritage Site, as well as for Studio...

, near Potsdam
Potsdam
Potsdam is the capital city of the German federal state of Brandenburg and part of the Berlin/Brandenburg Metropolitan Region. It is situated on the River Havel, southwest of Berlin city centre....

 and 25 kilometres (15.5 mi) from the center of Berlin, and the new institution was named Berlin-Babelsberg Observatory. There, he started installing a 26-inch Zeiss refractor and a 48-inch reflector
Reflecting telescope
A reflecting telescope is an optical telescope which uses a single or combination of curved mirrors that reflect light and form an image. The reflecting telescope was invented in the 17th century as an alternative to the refracting telescope which, at that time, was a design that suffered from...

, which should then become the largest telescope in Germany. While he did not get to operate them himself, due to delays caused by World War I, the refractor was much used by his son Georg and reflector by his less known grandson Wilfried
Wilfried Struve
Wilfried George Struve was a German scientist. He started his career as a fifth-generation astronomer, a direct successor in the famous family line of Friedrich Georg Wilhelm, Otto Wilhelm, Hermann, Georg Hermann Struve...

.
In 1905, Struve became professor of the University of Berlin and from 1904 until his death in 1920, he served as director of the Berlin-Babelsberg Observatory. Struve's death was accelerated by a heart illness which he suffered from during his late years and by a bad fall from a tram car in 1919. He broke a thigh, and while recovering in a sanatorium in Bad Herrenalb
Bad Herrenalb
Bad Herrenalb is a municipality in the district of Calw, in Baden-Württemberg, Germany. It is situated in the northern Black Forest, 15 km east of Baden-Baden, and 22 km southwest of Pforzheim....

, died of a heart attack.

Family matters

Whereas many colleagues described Struve as a stern and serious person, within his family, he was seen as a cultivated man, who enjoyed music and friends and was very proud of the Struve family traditions. Yet even among relatives, he was known as inflexible in matters of principle.

Struve married in 1885 to the daughter of a cousin of his father. They had a son Georg Otto Hermann
Georg Hermann Struve
Georg Otto Hermann Struve was a German astronomer from the Struve family and the son of Hermann Struve.Georg was born in 1886 in Tsarskoye Selo – a former Russian residence of the imperial family and visiting nobility, located south from the center of St. Petersburg. In 1895, his family...

 and a daughter Elisabeth. George was born on 29 December 1886 in Tsarskoye Selo
Tsarskoye Selo
Tsarskoye Selo is the town containing a former Russian residence of the imperial family and visiting nobility, located south from the center of St. Petersburg. It is now part of the town of Pushkin and of the World Heritage Site Saint Petersburg and Related Groups of Monuments.-History:In...

, Russia, and later became famous astronomer. Hermann's wife Eva Struve played important role in rescuing his nephew Otto
Otto Struve
Otto Struve was a Russian astronomer. In Russian, his name is sometimes given as Otto Lyudvigovich Struve ; however, he spent most of his life and his entire scientific career in the United States...

. After escaping from the Soviet Russia in 1920, for a year and half he was stranded penniless in Turkey. Otto wrote to his uncle for help, unaware of his death, but Eva asked assistance of Paul Guthnick, her late husband's successor at the Berlin-Babelsberg Observatory. Whereas Guthnick was not in position to offer job to Struve in Germany, he highly recommended Struve to the director of Yerkes Observatory
Yerkes Observatory
Yerkes Observatory is an astronomical observatory operated by the University of Chicago in Williams Bay, Wisconsin. The observatory, which calls itself "the birthplace of modern astrophysics," was founded in 1897 by George Ellery Hale and financed by Charles T. Yerkes...

 in Chicago
Chicago
Chicago is the largest city in the US state of Illinois. With nearly 2.7 million residents, it is the most populous city in the Midwestern United States and the third most populous in the US, after New York City and Los Angeles...

, who not only found job for Struve at Yerkes, but also arranged a visa for him and paid for his travel.

Research

As all astronomers of the Struve family, Herman was mostly working on establishing position and movements of single and double star
Double star
In observational astronomy, a double star is a pair of stars that appear close to each other in the sky as seen from Earth when viewed through an optical telescope. This can happen either because the pair forms a binary star, i.e...

s and satellites of the planets of the Solar System. In 1885, a 30-inch refracting telescope
Refracting telescope
A refracting or refractor telescope is a type of optical telescope that uses a lens as its objective to form an image . The refracting telescope design was originally used in spy glasses and astronomical telescopes but is also used for long focus camera lenses...

 was installed at Pulkovo, at the time the largest in the world (see great refractor
Great refractor
Great refractor refers to a large telescope with a lens, usually the largest refractor at an observatory with an equatorial mount. The preeminence and success of this style in observational astronomy was an era in telescope use in the 19th and early 20th century. Great refractors were large...

). Struve was the first user of that telescope, which he used mostly for determining positions of a large number of double star
Double star
In observational astronomy, a double star is a pair of stars that appear close to each other in the sky as seen from Earth when viewed through an optical telescope. This can happen either because the pair forms a binary star, i.e...

s. His other major topic was Saturn
Saturn
Saturn is the sixth planet from the Sun and the second largest planet in the Solar System, after Jupiter. Saturn is named after the Roman god Saturn, equated to the Greek Cronus , the Babylonian Ninurta and the Hindu Shani. Saturn's astronomical symbol represents the Roman god's sickle.Saturn,...

, but he also studied Mars, Neptune
Neptune
Neptune is the eighth and farthest planet from the Sun in the Solar System. Named for the Roman god of the sea, it is the fourth-largest planet by diameter and the third largest by mass. Neptune is 17 times the mass of Earth and is slightly more massive than its near-twin Uranus, which is 15 times...

 and the fifth moon of Jupiter
Jupiter
Jupiter is the fifth planet from the Sun and the largest planet within the Solar System. It is a gas giant with mass one-thousandth that of the Sun but is two and a half times the mass of all the other planets in our Solar System combined. Jupiter is classified as a gas giant along with Saturn,...

. He could not observe Uranus
Uranus
Uranus is the seventh planet from the Sun. It has the third-largest planetary radius and fourth-largest planetary mass in the Solar System. It is named after the ancient Greek deity of the sky Uranus , the father of Cronus and grandfather of Zeus...

 from Pulkovo because it was too far south. In 1888, Struve discovered libration of Hyperion
Hyperion (moon)
Hyperion , also known as Saturn VII, is a moon of Saturn discovered by William Cranch Bond, George Phillips Bond and William Lassell in 1848. It is distinguished by its irregular shape, its chaotic rotation, and its unexplained sponge-like appearance...

 (the sevenths moon of Saturn) and explained it by the perturbing action of the largest Saturn's moon, Titan
Titan (moon)
Titan , or Saturn VI, is the largest moon of Saturn, the only natural satellite known to have a dense atmosphere, and the only object other than Earth for which clear evidence of stable bodies of surface liquid has been found....

. The same year, he introduced method of intersatelite method of correcting orbital position of satellites. The method was rather successful because systematic errors in visual observations of some planets, such as Mars, were unacceptably large. Struve however realized that the method had flaws and recommended combining planet/satellite and intersatellite measurements. In 1892, Struve discovered libration of two other moons of Saturn, Mimas
Mimas (moon)
Mimas is a moon of Saturn which was discovered in 1789 by William Herschel. It is named after Mimas, a son of Gaia in Greek mythology, and is also designated Saturn I....

 and Enceladus
Enceladus (moon)
Enceladus is the sixth-largest of the moons of Saturn. It was discovered in 1789 by William Herschel. Until the two Voyager spacecraft passed near it in the early 1980s very little was known about this small moon besides the identification of water ice on its surface...

. His observations of the moon of Mars, Phobos
Phobos (moon)
Phobos is the larger and closer of the two natural satellites of Mars. Both moons were discovered in 1877. With a mean radius of , Phobos is 7.24 times as massive as Deimos...

, were later used by B. Sharpless in studying the secular acceleration of its orbit.

Struve was known not only as astronomer, but also as mathematician. In 1882, he introduced a function to describe the intensity of a luminous line. This function also describes solutions of Bessel's differential equation; it therefore is widely used in mathematics and is named as Struve function.

After moving to Königsberg Observatory, Struve built a 32.5-inch refractor telescope there and continued his work on the moons of Saturn, last observations of which he made in 1916. His other topics included study of atmospheric refraction
Atmospheric refraction
Atmospheric refraction is the deviation of light or other things like humanelectromagnetic wave from a straight line as it passes through the atmosphere due to the variation in air density as a function of altitude...

, stellar parallax
Parallax
Parallax is a displacement or difference in the apparent position of an object viewed along two different lines of sight, and is measured by the angle or semi-angle of inclination between those two lines. The term is derived from the Greek παράλλαξις , meaning "alteration"...

es, drawings of Jupiter, determination of the position of the Mars' equator, the amount of its oblateness and the rate of motion of the nodes.

Awards and honors

In 1897, Struve received the Damoiseau Prize
Marie-Charles Damoiseau
Baron Marie-Charles-Théodore de Damoiseau de Montfort was a French astronomer.Damoiseau left France during the French Revolution and worked as assistant director of the Lisbon Observatory. He returned to France in 1807.In 1825, he was elected a member of the French Academy of Sciences...

 from the French Academy of Sciences
French Academy of Sciences
The French Academy of Sciences is a learned society, founded in 1666 by Louis XIV at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French scientific research...

 and in 1903 the Gold Medal of the Royal Astronomical Society
Gold Medal of the Royal Astronomical Society
-History:In the early years, more than one medal was often awarded in a year, but by 1833 only one medal was being awarded per year. This caused a problem when Neptune was discovered in 1846, because many felt an award should jointly be made to John Couch Adams and Urbain Le Verrier...

, both for his work on satellites of Saturn. He was the third (after Friedrich Georg Wilhelm and Otto Wilhelm) member of Struve family to receive that medal. The asteroid
Asteroid
Asteroids are a class of small Solar System bodies in orbit around the Sun. They have also been called planetoids, especially the larger ones...

 768 Struveana
768 Struveana
768 Struveana is a minor planet orbiting the Sun. The asteroid was named jointly in honor of Friedrich Georg Wilhelm von Struve, Otto Wilhelm von Struve and Karl Hermann Struve.-External links:*...

was named in honor of Herman, Otto Wilhelm and Friedrich Georg Wilhelm Struve.
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK