Oskar Backlund
Encyclopedia
Johan Oskar Backlund was a Swedish
-Russia
n astronomer
. His name is sometimes given as Jöns Oskar Backlund, however even contemporary Swedish sources give "Johan". In Russia
, where he spent his entire career, he is known as Oskar Andreevich Baklund (Оскар Андреевич Баклунд). Russian sources sometimes give his dates of birth and death as April 16, 1846 and August 16, 1916, since Russia still used the Julian calendar
at the time.
, Sweden
and graduated from Uppsala University
in 1872. In 1876 he emigrated to Russia. He worked at Dorpat Observatory, in today's Tartu
, Estonia
, and then in 1879 worked at Pulkovo Observatory
, becoming director of the observatory from 1895 until his death.
He specialized in celestial mechanics
, and notably worked on calculating the orbit of Comet Encke
, taking into account the perturbations of various planets. He used observations of Comet Encke to try estimate the mass of Mercury
. Russian sources sometimes referred to the comet as Comet Encke-Backlund. He also carried out geodesic
studies in Spitsbergen
from 1898 to 1900. He became a member of the Saint Petersburg
Academy of Sciences in 1883, member of the Royal Swedish Academy of Sciences
in 1897 and Fellow of the Royal Society in 1911. He was elected a Foreign Honorary Member of the American Academy of Arts and Sciences
in 1914.
Named after him
Sweden
Sweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....
-Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...
n 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...
. His name is sometimes given as Jöns Oskar Backlund, however even contemporary Swedish sources give "Johan". In Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...
, where he spent his entire career, he is known as Oskar Andreevich Baklund (Оскар Андреевич Баклунд). Russian sources sometimes give his dates of birth and death as April 16, 1846 and August 16, 1916, since Russia still used the Julian calendar
Julian calendar
The Julian calendar began in 45 BC as a reform of the Roman calendar by Julius Caesar. It was chosen after consultation with the astronomer Sosigenes of Alexandria and was probably designed to approximate the tropical year .The Julian calendar has a regular year of 365 days divided into 12 months...
at the time.
Life
He was born in Länghem, in VästergötlandVästergötland
', English exonym: West Gothland, is one of the 25 traditional non-administrative provinces of Sweden , situated in the southwest of Sweden. In older English literature one may also encounter the Latinized version Westrogothia....
, Sweden
Sweden
Sweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....
and graduated from Uppsala University
Uppsala University
Uppsala University is a research university in Uppsala, Sweden, and is the oldest university in Scandinavia, founded in 1477. It consistently ranks among the best universities in Northern Europe in international rankings and is generally considered one of the most prestigious institutions of...
in 1872. In 1876 he emigrated to Russia. He worked at Dorpat Observatory, in today's 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...
, Estonia
Estonia
Estonia , officially the Republic of Estonia , is a state in the Baltic region of Northern Europe. It is bordered to the north by the Gulf of Finland, to the west by the Baltic Sea, to the south by Latvia , and to the east by Lake Peipsi and the Russian Federation . Across the Baltic Sea lies...
, and then in 1879 worked at 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...
, becoming director of the observatory from 1895 until his death.
He specialized in celestial mechanics
Celestial mechanics
Celestial mechanics is the branch of astronomy that deals with the motions of celestial objects. The field applies principles of physics, historically classical mechanics, to astronomical objects such as stars and planets to produce ephemeris data. Orbital mechanics is a subfield which focuses on...
, and notably worked on calculating the orbit of Comet Encke
Comet Encke
Comet Encke or Encke's Comet is a periodic comet that completes an orbit of the Sun once every three years — the shortest period of any known comet...
, taking into account the perturbations of various planets. He used observations of Comet Encke to try estimate the mass of Mercury
Mercury (planet)
Mercury is the innermost and smallest planet in the Solar System, orbiting the Sun once every 87.969 Earth days. The orbit of Mercury has the highest eccentricity of all the Solar System planets, and it has the smallest axial tilt. It completes three rotations about its axis for every two orbits...
. Russian sources sometimes referred to the comet as Comet Encke-Backlund. He also carried out geodesic
Geodesy
Geodesy , also named geodetics, a branch of earth sciences, is the scientific discipline that deals with the measurement and representation of the Earth, including its gravitational field, in a three-dimensional time-varying space. Geodesists also study geodynamical phenomena such as crustal...
studies in Spitsbergen
Spitsbergen
Spitsbergen is the largest and only permanently populated island of the Svalbard archipelago in Norway. Constituting the western-most bulk of the archipelago, it borders the Arctic Ocean, the Norwegian Sea and the Greenland Sea...
from 1898 to 1900. He became a member of the Saint 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...
Academy of Sciences in 1883, member of the Royal Swedish Academy of Sciences
Royal Swedish Academy of Sciences
The Royal Swedish Academy of Sciences or Kungliga Vetenskapsakademien is one of the Royal Academies of Sweden. The Academy is an independent, non-governmental scientific organization which acts to promote the sciences, primarily the natural sciences and mathematics.The Academy was founded on 2...
in 1897 and Fellow of the Royal Society in 1911. He was elected a Foreign Honorary Member of the American Academy of Arts and Sciences
American Academy of Arts and Sciences
The American Academy of Arts and Sciences is an independent policy research center that conducts multidisciplinary studies of complex and emerging problems. The Academy’s elected members are leaders in the academic disciplines, the arts, business, and public affairs.James Bowdoin, John Adams, and...
in 1914.
Family
He was married to Ulrika Catharina Widebeck. Their daughter Elsa Carolina Backlund (February 25, 1880 – April 19, 1974) became a well-known artist (she married Ulrik Fredrik Adolf Hugo Celsing, and was known under the name Elsa Backlund-Celsing). Their son Helge Gotrik Backlund (September 3, 1878 – 1958) was a geologist.Honors
Awards- Gold Medal of the Royal Astronomical SocietyGold 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...
(1909) - Bruce MedalBruce MedalThe Catherine Wolfe Bruce Gold Medal is awarded every year by the Astronomical Society of the Pacific for outstanding lifetime contributions to astronomy. It is named after Catherine Wolfe Bruce, an American patroness of astronomy, and was first awarded in 1898...
(1914)
Named after him
- The crater BacklundBacklund (crater)Backlund is a worn lunar crater that lies on the far side of the Moon, beyond the eastern limb. It lies astride the southern rim of the walled plain Pasteur, to the west of the crater Hilbert. Further to the west-southwest is Sklodowska. The north and south ends of Backlund are more worn and eroded...
on the MoonMoonThe Moon is Earth's only known natural satellite,There are a number of near-Earth asteroids including 3753 Cruithne that are co-orbital with Earth: their orbits bring them close to Earth for periods of time but then alter in the long term . These are quasi-satellites and not true moons. For more... - AsteroidAsteroidAsteroids are a class of small Solar System bodies in orbit around the Sun. They have also been called planetoids, especially the larger ones...
856 Backlunda856 Backlunda-External links:*...
External links
- Bruce Medal page
- Awarding of Bruce Medal
- Awarding of RAS gold medal
- Backlund, Johan Oskar (Svenskt biografiskt handlexikon) in Project RunebergProject RunebergProject Runeberg is an initiative patterned after Project Gutenberg that publishes freely available electronic versions of books significant to the culture and history of the Nordic countries...
(in Swedish) - I:56 (Svenskt biografiskt handlexikon) in Project Runeberg (in Swedish)
- II:795 (Svenskt biografiskt handlexikon) in Project Runeberg (in Swedish)