Daniel Melander, knighted Melanderhjelm, (29 October 1726–8 January 1810) was a Swedish
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 ...
and
astronomer
An astronomer is a scientist in the field of astronomy who focuses on a specific question or field outside the scope of Earth. Astronomers observe astronomical objects, such as stars, planets, natural satellite, moons, comets and galaxy, galax ...
, professor and rector of
Uppsala University
Uppsala University (UU) () is a public university, public research university in Uppsala, Sweden. Founded in 1477, it is the List of universities in Sweden, oldest university in Sweden and the Nordic countries still in operation.
Initially fou ...
, secretary of the
Royal Swedish Academy of Sciences
The Royal Swedish Academy of Sciences () is one of the Swedish Royal Academies, royal academies of Sweden. Founded on 2 June 1739, it is an independent, non-governmental scientific organization that takes special responsibility for promoting nat ...
Daniel Melander's father Simon Melander was a school headmaster in
Stockholm
Stockholm (; ) is the Capital city, capital and List of urban areas in Sweden by population, most populous city of Sweden, as well as the List of urban areas in the Nordic countries, largest urban area in the Nordic countries. Approximately ...
and vicar in
Enköping
Enköping is a locality and the seat of Enköping Municipality, Uppsala County, Sweden with 30,000 inhabitants in 2018.
Geography
Enköping is situated near Lake Mälaren, about 78 km west of Stockholm.
A comparably large number of S ...
and
Gävle
Gävle ( ; ) is a Urban areas in Sweden, city in Sweden, the seat of Gävle Municipality and the capital of Gävleborg County. It had 79,004 inhabitants in 2020, which makes it the List of cities in Sweden, 13th-most-populated city in Sweden. I ...
, and a descendant of Archbishop Olaus Martini from Bureätten. His mother was Justina Margaretha Djurberg who was the daughter of Daniel Djurberg and Margaretha Theel.
The father's wish was that Daniel Melander would become a vicar like himself, but after the son studied
Euclid
Euclid (; ; BC) was an ancient Greek mathematician active as a geometer and logician. Considered the "father of geometry", he is chiefly known for the '' Elements'' treatise, which established the foundations of geometry that largely domina ...
with
Samuel Klingenstierna
Samuel Klingenstierna (18 August 1698 – 26 October 1765) was a Swedish mathematician and scientist. He started his career as a lawyer but soon moved to natural philosophy. As a student he gave lectures on the then novel mathematical analysis of ...
, he changed the focus of his studies. He became a student at
Uppsala University
Uppsala University (UU) () is a public university, public research university in Uppsala, Sweden. Founded in 1477, it is the List of universities in Sweden, oldest university in Sweden and the Nordic countries still in operation.
Initially fou ...
in 1740, master of philosophy in 1752, lecturer in mathematical
physics
Physics is the scientific study of matter, its Elementary particle, fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. "Physical science is that department of knowledge whi ...
the same year, assistant professor of physics in 1757, professor of astronomy in 1761. He was knighted in 1778 with the name Melanderhjelm. He was given leave of absence in 1782 and was called to
Stockholm
Stockholm (; ) is the Capital city, capital and List of urban areas in Sweden by population, most populous city of Sweden, as well as the List of urban areas in the Nordic countries, largest urban area in the Nordic countries. Approximately ...
in 1788 to assist with the organization of the
Royal Swedish Academy of War Sciences
The Royal Swedish Academy of War Sciences () is one of the Royal Academies in Sweden and was founded on 12 November 1796 by Gustaf Wilhelm af Tibell. The academy is an independent organization and a forum for military (army and air force) and de ...
. In 1796 or 1797 he was appointed secretary of the
Royal Swedish Academy of Sciences
The Royal Swedish Academy of Sciences () is one of the Swedish Royal Academies, royal academies of Sweden. Founded on 2 June 1739, it is an independent, non-governmental scientific organization that takes special responsibility for promoting nat ...
and remained in the post until 1803. In 1801 he received the title of councillor (kansliråds). Melanderhjelm was a member of the
Royal Society of Sciences in Uppsala
The Royal Society of Sciences in Uppsala (), is the oldest of the royal academies in Sweden, having been founded in 1710. The society has, by royal decree of 1906, 50 Swedish fellows and 100 foreign.
Early members included Emanuel Swedenborg an ...
, the Academy of Sciences (1765), the
Royal Swedish Academy of Letters, History and Antiquities
The Royal Swedish Academy of Letters, History and Antiquities also called simply the Royal Academy of Letters or Vitterhetsakademien abbreviated KVHAA ( or or ) is the Sweden, Swedish Swedish Royal Academies, royal academy for the Humanities. Its ...
(1780) and the Royal Swedish Academy of War Sciences.
He was married to his cousin Margaretha Katarina Frondin, daughter of chamber councillor Professor Elias Frondin and Gunilla Rommel, and sister of Berge Frondin. He survived both his wife and children, so that his family line ended in 1810. He is buried in
Uppsala Cathedral
Uppsala Cathedral () is a cathedral located between the University Hall (Uppsala University), University Hall of Uppsala University and the Fyris river in the centre of Uppsala, Sweden. A church of the Church of Sweden, the national church, in t ...
.
Work as astronomer
Melanderhjelm published widely on astronomy. To support academic teaching, he published ''Conspectus praelectionum academicarum continens fundamenta astronomiae'' (1779), which was later published in a somewhat revised and expanded form in Swedish under the title ''Astronomie'' (1795). Its Latin edition was also used abroad well into the 19th century. His more scientific works were mainly on
celestial mechanics
Celestial mechanics is the branch of astronomy that deals with the motions of objects in outer space. Historically, celestial mechanics applies principles of physics (classical mechanics) to astronomical objects, such as stars and planets, to ...
, especially the general theory of the
Solar System
The Solar SystemCapitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Sola ...
and
Lunar theory
Lunar theory attempts to account for the motions of the Moon. There are many small variations (or perturbation (astronomy), perturbations) in the Moon's motion, and many attempts have been made to account for them. After centuries of being problema ...
.
In ''Om den synliga verldens större eller mindre varaktighet'' (on the greater or lesser duration of the visible world, 1771–1772), Melanderhjelm tried to show that among all possible laws of attraction the actually existing one is the most suitable for the existence of the world system. Among his works on the theory of the Moon was ''De theoria lunae commentarii'' (1769), in which, with the theory of gravitation as a starting point, the motion of the Moon is determined, and related problems are solved according to other, partly simpler, methods than those given by Clairaut,
Euler
Leonhard Euler ( ; ; ; 15 April 170718 September 1783) was a Swiss polymath who was active as a mathematician, physicist, astronomer, logician, geographer, and engineer. He founded the studies of graph theory and topology and made influential ...
and
Lagrange
Joseph-Louis Lagrange (born Giuseppe Luigi Lagrangiatransits of Venus, the atmospheres of the
planets
A planet is a large, rounded astronomical body that is generally required to be in orbit around a star, stellar remnant, or brown dwarf, and is not one itself. The Solar System has eight planets by the most restrictive definition of the te ...
and the method of determining the
equation of time
The equation of time describes the discrepancy between two kinds of solar time. The two times that differ are the apparent solar time, which directly tracks the diurnal motion of the Sun, and mean solar time, which tracks a theoretical mean Sun ...
. Melanderhjelm also initiated the 1802 meridian survey in Lapland and wrote the foreword to the account thereof.
Work as mathematician
Melanderhjelm also wrote several works on pure
mathematics
Mathematics is a field of study that discovers and organizes methods, Mathematical theory, theories and theorems that are developed and Mathematical proof, proved for the needs of empirical sciences and mathematics itself. There are many ar ...
. He also tried to support academic teaching in this area and to this end published a new edition of Newton's work on the quadrature of
curves
A curve is a geometrical object in mathematics.
Curve(s) may also refer to:
Arts, entertainment, and media Music
* Curve (band), an English alternative rock music group
* Curve (album), ''Curve'' (album), a 2012 album by Our Lady Peace
* Curve ( ...
, which he provided with notes and additions. In addition, he wrote on
integral calculus
In mathematics, an integral is the continuous analog of a sum, which is used to calculate areas, volumes, and their generalizations. Integration, the process of computing an integral, is one of the two fundamental operations of calculus,Int ...
and the theory for the integration of differential equations; however, his results were somewhat specific and contained only fairly simple substitution formulas.
Melanderhjelm on literary subjects wrote, for example ''Om nyttan af ett eget de lärdes språk'' (on the benefit of one's own language).