Theodor von Oppolzer (26 October 1841 – 26 December 1886) was an Austrian

astronomer An astronomer is a scientist in the field of astronomy who focuses their studies on a specific question or field outside the scope of Earth. They observe astronomical objects such as stars, planets, moons, comets and galaxies – in either o ...

and

mathematician A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, mathematical structure, structure, space, Mathematica ...

Bohemian Bohemian or Bohemians may refer to: *Anything of or relating to Bohemia Beer * National Bohemian, a brand brewed by Pabst * Bohemian, a brand of beer brewed by Molson Coors Culture and arts * Bohemianism, an unconventional lifestyle, orig ...

origin. The son of the

physician A physician (American English), medical practitioner (Commonwealth English), medical doctor, or simply doctor, is a health professional who practices medicine, which is concerned with promoting, maintaining or restoring health through th ...

Johann Ritter von Oppolzer Johann Ritter von Oppolzer (4 August 1808 – 16 April 1871) was an Austrian physician born in Nové Hrady, Bohemia. He was the father of the astronomer Theodor von Oppolzer (1841–1886). In 1835 he earned his medical doctorate at the Un ...

, Theodor was born in

Prague Prague ( ; cs, Praha ; german: Prag, ; la, Praga) is the capital and largest city in the Czech Republic, and the historical capital of Bohemia. On the Vltava river, Prague is home to about 1.3 million people. The city has a temperate ...

. He completed his graduate studies in

medicine Medicine is the science and Praxis (process), practice of caring for a patient, managing the diagnosis, prognosis, Preventive medicine, prevention, therapy, treatment, Palliative care, palliation of their injury or disease, and Health promotion ...

at the

University of Vienna The University of Vienna (german: Universität Wien) is a public research university located in Vienna, Austria. It was founded by Duke Rudolph IV in 1365 and is the oldest university in the German-speaking world. With its long and rich h ...

, gaining a

Ph.D. A Doctor of Philosophy (PhD, Ph.D., or DPhil; Latin: or ') is the most common degree at the highest academic level awarded following a course of study. PhDs are awarded for programs across the whole breadth of academic fields. Because it is a ...

in 1865. He also owned a private observatory. He began teaching theoretical astronomy and geodesics at the University of Vienna in 1866. By 1875 he was appointed a professor. In 1873 he became the director of the Austrian Geodetic Survey, and in 1886 he was elected president of the

International Geodetic Association The International Association of Geodesy (IAG) is a constituent association of the International Union of Geodesy and Geophysics. Overview The precursors to the IAG were arc measurement campaigns. The IAG was founded in 1862 as the ''Mitteleuro ...

. He was considered a highly capable astronomer and mathematician. For example, he was reputed to have memorized the values of 14,000

logarithm In mathematics, the logarithm is the inverse function to exponentiation. That means the logarithm of a number to the base is the exponent to which must be raised, to produce . For example, since , the ''logarithm base'' 10 of ...

s. In 1868 he led an expedition to observe a

solar eclipse A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby obscuring the view of the Sun from a small part of the Earth, totally or partially. Such an alignment occurs during an eclipse season, approximately every six mo ...

. Afterward (1887) he authored the '' Canon der Finsternisse'', an authoritative compilation of the 8,000 solar and 5,200 lunar eclipses from 1,200 B.C. until 2,161 A.D. This was widely recognized as one of the greatest computational feats of its day. Oppolzer authored over 300 papers, with most concerning the orbital elements of

comet A comet is an icy, small Solar System body that, when passing close to the Sun, warms and begins to release gases, a process that is called outgassing. This produces a visible atmosphere or Coma (cometary), coma, and sometimes also a Comet ta ...

s and

asteroid An asteroid is a minor planet of the Solar System#Inner solar system, inner Solar System. Sizes and shapes of asteroids vary significantly, ranging from 1-meter rocks to a dwarf planet almost 1000 km in diameter; they are rocky, metallic o ...

s. He also published a two-volume manual on the determination of the orbital elements of comets and planets.Th. von Oppolzer, ''Lehrbuch zur Bahnbestimmung der Kometen und Planeten'' (Leipzig: Engelmann, 1870/1880), 2 vols. - a second edition of the first volume appeared in 1882. Both of his works served as standard astronomy references for many years. He was working on an improved theory of lunar motion at the time of his death. His son

Egon von Oppolzer Egon is a variant of the male given name Eugene (given name), Eugene. It is most commonly found in Austria, the Czech Republic, Germany, Estonia, Hungary, Slovakia, Sweden, Denmark, and parts of the Netherlands and Belgium. The name can also be ...

also became a distinguished astronomer.

Awards and honors

* Elected to the Imperial Academy of Sciences of Vienna, 1882. * Elected to the American National Academy of Sciences, 1883. * The crater Oppolzer on the

Moon The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width ...

is named after him. *

Asteroid An asteroid is a minor planet of the Solar System#Inner solar system, inner Solar System. Sizes and shapes of asteroids vary significantly, ranging from 1-meter rocks to a dwarf planet almost 1000 km in diameter; they are rocky, metallic o ...

1492 Oppolzer 149 may refer to: *149 (number), a natural number *AD 149, a year in the 2nd century AD *149 BC, a year in the 2nd century BC *British Airways Flight 149, a flight from LHR to Kuwait City International Airport; the aircraft flying this flight was d ...

was named for him. In addition asteroids were named for his wife (

237 Coelestina Coelestina (minor planet designation: 237 Coelestina) is a typical main belt asteroid. It was discovered by Johann Palisa on 27 June 1884 in Vienna and was named after Coelestine who is one the descendants of the greek philosopher Tate Santiago ...

), and his two daughters (

153 Hilda Hilda (minor planet designation: 153 Hilda) is a large asteroid in the outer main belt, with a diameter of 170 km. Because it is composed of primitive carbonaceous materials, it has a very dark surface. It was discovered by Johann Palisa on ...

and

228 Agathe Agathe (minor planet designation: 228 Agathe) is a stony main belt asteroid, about 9 kilometers in diameter. It was discovered by Johann Palisa on 19 August 1882 at Vienna Observatory, Austria. Photometric observations during 2003 showed a rota ...

). 153 Hilda then gave its name to the

Hilda group The Hilda asteroids (adj. ''Hildian'') are a dynamical group of more than 5,000 asteroids located beyond the asteroid belt but within Jupiter's orbit, in a 3:2 orbital resonance with Jupiter. The namesake is the asteroid 153 Hilda. Hildas move ...

References

External links

* {{DEFAULTSORT:Oppolzer, Theodor von 1841 births 1886 deaths 19th-century Austrian astronomers 19th-century Austrian mathematicians University of Vienna alumni Academic staff of the University of Vienna German Bohemian people Bohemian nobility Austrian knights Austrian people of German Bohemian descent Scientists from Prague Mathematicians from Prague Austro-Hungarian mathematicians Foreign associates of the National Academy of Sciences