Commemorative plaque of Th. Brorsen on the castle wall in Žamberk

Theodor Johan Christian Ambders Brorsen (July 29, 1819 – March 31, 1895) was a Danish astronomer best known for his discovery of five comets, including the lost periodic comet 5D/Brorsen and the periodic comet 23P/Brorsen-Metcalf. Events 1014 - Byzantine-Bulgarian Wars: Battle of Kleidion: Byzantine emperor Basil II inflicts a decisive defeat Year 1819 ( MDCCCXIX) was a Common year starting on Friday (link will display the full calendar in the Gregorian Calendar (or a Common year Events 307 - After divorcing his wife Minervina, Constantine marries Fausta, the daughter of the retired Roman Emperor Year 1895 ( MDCCCXCV) was a Common year starting on Tuesday (link will display full calendar of the Gregorian calendar (or a Common year Historically Astronomy was more concerned with the classification and description of phenomena in the sky while Astrophysics attempted to explain these phenomena A comet is a small Solar System body that orbits the Sun and when close enough to the Sun exhibits a visible coma (atmosphere or a tail — 5D/Brorsen is a comet discovered February 26, 1846, by the Danish Astronomer Theodor Brorsen. Comet Brorsen-Metcalf is a Periodic comet in our solar system that was first discovered by Theodor Brorsen ( Altona, Germany) on July 20

Life

Theodor Johan Christian Ambders Brorsen was born in Nordborg on the island Als (South Jutland) as son of the captain Christian August Brorsen (1793-1840) and his wife Annette Margrethe Gerhardine Schumacher (1788-1855). South Jutland (Sønderjylland is the name for the region south of the Kongeå in Jutland. He got his three middle names after the maternal grandfather of his mother, the Nordborg counsel Johan Christan Ambders (1710-1795). After the amicable divorce of his parents in 1822, Brorsen grew up at his mother’s. Her good financial circumstances allowed him to attend the school of the Moravians in Christiansfeld (1826-1829) and then (1830-1839) the Latin school in Flensburg. Christiansfeld is a town in Kolding municipality in southern Jutland in Region Syddanmark in Denmark. Flensburg ( Danish: Flensborg, Low Saxon: Flensborg, North Frisian: Flansborj) is an independent town in By request of his mother, Brorsen studied law in Kiel (1839), Berlin (1840), Heidelberg (1841) and again in Kiel (1842), until he decided to follow his inclinations and studied astronomy in Kiel since 1844. For the city in the United States, see Kiel Wisconsin. For the name see Kiel (name. Berlin is the capital city and one of sixteen states of Germany. Heidelberg is a city in Baden-Württemberg, Germany. As of 2006 over 140000 people live within the city's area

Brorsen worked at the astronomical observatory of Kiel (1846) and of Altona, Hamburg (1847). Altona (ˈaltona is the westernmost urban borough ( Bezirk) of the German city state of Hamburg, on the right bank of the Elbe He rejected a job offer from the astronomical oberservatory "Rundetaarn" (Round tower) in Copenhagen. Copenhagen (ˌkəʊpənˈheɪgən ˌkəʊpənˈhɑːgən ˈkəʊpənˌheɪgən ˈkəʊpənˌhɑːgən kʰøb̥ənˈhɑʊ̯ˀn kʰøb̥m̩ˈhɑʊ̯ˀn is the capital and largest city Instead, he accepted a job at the private observatory of baron John Parish (1774-1858, an Englishman, also known as Freiherr von Senftenberg) in Žamberk (at the time called Senftenberg) in the present-day Czech Republic. Žamberk (ˈʒambɛrk Senftenberg is a town in the Pardubice Region of the Czech Republic. The Czech Republic ( ˈt͡ʃɛskaː ˈrɛpuˌblɪka short form in Česko ˈt͡ʃɛskɔ also called Czechia, When the post of the director of the astronomical observatory of Altona became vacant in 1854, Brorsen applied to it, but was not chosen. After the death of baron Parish in 1858, his heirs had the observatory of Senftenberg dismantled and the astronomical instruments sold although Brorsen offered to continue his work for free. Nevertheless Brorsen remained twelve further years in Senftenberg and continued his observations with his own instruments.

In 1870, he returned to his home town Nordborg in South Jutland, which had become Prussian since the Second War of Schleswig of 1864 and subsequently was German from 1871 up to the plesbiscite of 1920. The First Schleswig War occurred in 1848–1851. The Second Schleswig War (2 In 1874, Brorsen moved into the house Løjtertoft 11, where he lived until his death. His unmarried half sister Amalie Petrine Brorsen (1832-1911) kept house for him. In his years in Nordborg, however, Brorsen hardly occupied himself with astronomy any more. His main interests were meteorology (also observations of Northern Lights) as well as botany, especially orchid breeding. Meteorology (from Greek grc μετέωρος metéōros, "high in the sky" and grc -λογία -logia) is the Interdisciplinary Botany, plant science(s, phytology, or plant biology is a branch of Biology and is the scientific study of plant Life

Brorsens gravestone in the cemetery of Nordborg

Personally, Brorsen was an introverted character with relationship anxieties. He twice broke off an engagement in the last moment (first one to Louise Lassen from Sønderborg, then another one to Miss Bernkopf from Žamberk) and hence remained unmarried. Besides, there are testimonies that Brorsen developed self-willed habits in the last 25 years of his life spent in Nordborg. He did not take much care for his clothing, he let his hair grow long, and when his boots pressed his feet, he cut holes into his boots in the tight places. He used to take a daily bath in the Oldenor, a lake in Nordborg; in winter, he hoed a hole into the ice for that purpose. Brorsen died at 75 years of age and was buried on April 5, 1895, in the cemetery of Nordborg where his grave is still preserved today.

Discoveries

• Brorsen discovered five comets: 1846 III, 1846 VII, 1847 V, 1851 III and 1851 IV. Two of them were named after Brorsen as they are periodic comets. The comet 1846 III is called Brorsen and the comet 1847 V is named Brorsen-Metcalf (because Joel Hastings Metcalf was its rediscoverer in 1919).

The comet 5D/Brorsen (with a period of 5. 5D/Brorsen is a comet discovered February 26, 1846, by the Danish Astronomer Theodor Brorsen. 46 years) was last seen in 1879. In all, five of its rotations around the sun were observed. It belonged to the Jupiter comet family, whose comets can be short-lived so it may not exist any longer today.

The comet 23P/Brorsen-Metcalf (with a period of 69. Comet Brorsen-Metcalf is a Periodic comet in our solar system that was first discovered by Theodor Brorsen ( Altona, Germany) on July 20 06 years) was observed in 1847, 1919 and 1989. It belongs to the Halley comet family and is to be expected for 2059 again.

• In 1850, Brorsen (re-)discovered an emission nebula in the constellation Orion, NGC 2024, also known as flame nebula, which had already been observed, however, by William Herschel in 1786, as we know today. An emission nebula is a Cloud of Ionized Gas ( ie a plasma) emitting light of various colors Orion (ɒˈraɪən a Constellation often referred to as The Hunter, is a prominent constellation one of the largest and perhaps the best-known and most conspicuous Sir Frederick William Herschel FRS KH ( 15 November 1738 – 25 August 1822) was a German -born British

• Brorsen might have discovered a sixth comet on March 16, 1854; this discovery could not be confirmed by other astronomers, though.

• In 1854, Brorsen published the first thorough investigations of the so-called gegenschein (counter glow) of the Zodiacal light. Gegenschein ( very roughy like GAY-guhn-shine German for "counter shine" is a faint brightening of the night sky in the region of the Antisolar The zodiacal light is a faint roughly triangular whitish glow seen in the night sky which appears to extend up from the vicinity of the Sun along the Ecliptic He was also able to explain that phenomenon correctly. Besides, Brorsen was the first to discover that the Zodiacal light can embrace the complete sky, because under favorable conditions, a feeble light bridge connecting the Zodiacal light and the counter glow can be observed.

• In 1856, Brorsen discovered a globular cluster in the constellation Serpens, which was later catalogued as NGC 6539. A globular cluster is a spherical collection of Stars that orbits a galactic core as a Satellite. Serpens (ˈsɝpənz Latin for " Snake " is one of the 88 modern Constellations and was also one of the 48 listed by Ptolemy.

• Further, Brorsen investigated the occultations and proper motions of stars. In Shia Islam The Occultation is a term used to designate the hidden state of the Imam of the Time. The proper motion of a Star is the measurement of its change in position in the sky over time after Improper motions are accounted for In the field of theoretical astronomy, Brorsen calculated the perihelia of comet and planet orbits. In Celestial mechanics, an apsis, plural apsides (ˈæpsɨdɪːz is the point of greatest or least distance of the Elliptical orbit of an object from

Honors

• For each of his first three comet discoveries, Brorsen was rewarded a golden comet medal by the Danish king Christian VIII. The medal which he got in 1846 can be seen today in the museum at Sønderborg castle, see here.

• Brorsen was appointed a corresponding member of the nature historic society in Žamberk in 1850.

• In Nordborg, a street is named after Brorsen today (Th. Brorsens vej).

• The asteroid 3979, which was discovered by A. Mrkos in Klet on November 8, 1983, was named "Brorsen" on proposal of J. Tichá (MPC 27734 – 1996 August 28). Asteroids, sometimes called Minor planets or planetoids', are bodies—primarily of the inner Solar System —that are smaller than planets but Biography Mrkos entered the University in Brno in 1938 His studies were interrupted by the onset of World War II, and in 1945 he became a staff member

Literature

• Sven Houmøller, Otto Kryck: Familien Brorsen fra Nordborg. Copenhagen 1949, p. 25-28 (listing the previous literature).

• Hertha Raben Petersen: Theodor Brorsen. Astronom. Nordborg 1986. ISBN 87-88558-053

External links

• photo
• biography in Czech
• photos of comet Brorsen-Metcalf
• further photos of comet Brorsen-Metcalf
• cometography of comet 5D/Brorsen