Anders Jonas Ångström (; 13 August 181421 June 1874) was a Swedish
physicist
A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe.
Physicists generally are interested in the root or ultimate caus ...
and one of the founders of the science of
spectroscopy
Spectroscopy is the field of study that measures and interprets the electromagnetic spectra that result from the interaction between electromagnetic radiation and matter as a function of the wavelength or frequency of the radiation. Matter wa ...
.
[P.Murdin (2000): "Angstrom" chapter in ''Encyclopedia of Astronomy and Astrophysics''. ]
Ångström is also well known for his studies of
astrophysics
Astrophysics is a science that employs the methods and principles of physics and chemistry in the study of astronomical objects and phenomena. As one of the founders of the discipline said, Astrophysics "seeks to ascertain the nature of the h ...
, heat transfer,
terrestrial magnetism
Earth's magnetic field, also known as the geomagnetic field, is the magnetic field that extends from Earth's interior out into space, where it interacts with the solar wind, a stream of charged particles emanating from the Sun. The magnetic fi ...
, and the
aurora borealis
An aurora (plural: auroras or aurorae), also commonly known as the polar lights, is a natural light display in Earth's sky, predominantly seen in high-latitude regions (around the Arctic and Antarctic). Auroras display dynamic patterns of br ...
. In 1852, Ångström formulated in ''Optiska undersökningar'' (Optical investigations), a law of absorption, later modified somewhat and known as
Kirchhoff's law of thermal radiation
In heat transfer, Kirchhoff's law of thermal radiation refers to wavelength-specific radiative emission and absorption by a material body in thermodynamic equilibrium, including radiative exchange equilibrium. It is a special case of Onsage ...
.
Biography
Anders Jonas Ångström was born in
Medelpad
Medelpad ( or ) is a historical province or ''landskap'' in the north of Sweden. It borders Hälsingland, Härjedalen, Jämtland, Ångermanland and the Gulf of Bothnia.
The province is a part of Norrland and as such considered to be Northern ...
to Johan Ångström, and schooled in
Härnösand
Härnösand () is a locality and the seat of Härnösand Municipality in Västernorrland County, Sweden with 17,556 inhabitants in 2010. It is called "the gate to the High Coast" because of the world heritage landscape just a few miles north of Hà ...
. He moved to
Uppsala
Uppsala (, or all ending in , ; archaically spelled ''Upsala'') is the county seat of Uppsala County and the List of urban areas in Sweden by population, fourth-largest city in Sweden, after Stockholm, Gothenburg, and Malmö. It had 177,074 inha ...
in 1833 and was educated at
Uppsala University
Uppsala University ( sv, Uppsala universitet) 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 opera ...
, where in 1839 he became
docent
The title of docent is conferred by some European universities to denote a specific academic appointment within a set structure of academic ranks at or below the full professor rank, similar to a British readership, a French " ''maître de conf ...
in physics. In 1842 he went to the
Stockholm Observatory
The Stockholm Observatory ( sv, Stockholms observatorium, 050) is an astronomical observatory and institution in Stockholm, Sweden, founded in the 18th century and today part of Stockholm University. In 1931, the new Stockholm Observatory ( sv, ...
to gain experience in practical astronomical work, and the following year he was appointed keeper of the
Uppsala Astronomical Observatory
The Uppsala Astronomical Observatory (UAO), Astronomiska observatoriet i Uppsala) is the oldest astronomical observatory in Sweden. It was founded in 1741, though there was a professorial chair of astronomy at the University of Uppsala from 1593 ...
.
Intrigued by
terrestrial magnetism
Earth's magnetic field, also known as the geomagnetic field, is the magnetic field that extends from Earth's interior out into space, where it interacts with the solar wind, a stream of charged particles emanating from the Sun. The magnetic fi ...
he recorded observations of fluctuations in magnetic intensity in various parts of Sweden, and was charged by the Stockholm Academy of Sciences with the task, not completed until shortly before his death, of working out the magnetic data obtained by on her voyage around the world in 1851 to 1853.
In 1858, he succeeded Adolph Ferdinand Svanberg in the chair of physics at Uppsala. His most important work was concerned with
heat
In thermodynamics, heat is defined as the form of energy crossing the boundary of a thermodynamic system by virtue of a temperature difference across the boundary. A thermodynamic system does not ''contain'' heat. Nevertheless, the term is al ...
conduction and
spectroscopy
Spectroscopy is the field of study that measures and interprets the electromagnetic spectra that result from the interaction between electromagnetic radiation and matter as a function of the wavelength or frequency of the radiation. Matter wa ...
. In his
optical
Optics is the branch of physics that studies the behaviour and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behaviour of visible, ultravio ...
researches, ''Optiska Undersökningar'', presented to the
Royal Swedish Academy of Sciences
The Royal Swedish Academy of Sciences ( sv, Kungliga Vetenskapsakademien) 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 ...
in 1853, he not only pointed out that the electric spark yields two superposed spectra, one from the metal of the electrode and the other from the gas in which it passes, but deduced from
Leonhard Euler
Leonhard Euler ( , ; 15 April 170718 September 1783) was a Swiss mathematician, physicist, astronomer, geographer, logician and engineer who founded the studies of graph theory and topology and made pioneering and influential discoveries in ma ...
's theory of resonance that an incandescent gas emits luminous rays of the same refrangibility as those it can absorb.
[See:
* Note: Although Ångström submitted his paper to the Swedish Royal Academy of Science on 16 February 1853, it was published in the volume for Academy's proceedings of 1852.
*
* ] This statement, as Sir
Edward Sabine
Sir Edward Sabine ( ; 14 October 1788 – 26 June 1883) was an Irish astronomer, geophysicist, ornithologist, explorer, soldier and the 30th president of the Royal Society.
He led the effort to establish a system of magnetic observatories in ...
remarked when awarding him the
Rumford medal of the
Royal Society
The Royal Society, formally The Royal Society of London for Improving Natural Knowledge, is a learned society and the United Kingdom's national academy of sciences. The society fulfils a number of roles: promoting science and its benefits, re ...
in 1872, contains a fundamental principle of
spectrum analysis, and though overlooked for a number of years it entitles him to rank as one of the founders of spectroscopy.
From 1861 onward, he paid special attention to the solar spectrum. His combination of the
spectroscope
An optical spectrometer (spectrophotometer, spectrograph or spectroscope) is an instrument used to measure properties of light over a specific portion of the electromagnetic spectrum, typically used in spectroscopic analysis to identify mate ...
with photography for the study 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 "Solar S ...
resulted in proving that the
Sun
The Sun is the star at the center of the Solar System. It is a nearly perfect ball of hot plasma, heated to incandescence by nuclear fusion reactions in its core. The Sun radiates this energy mainly as light, ultraviolet, and infrared radi ...
's atmosphere contains
hydrogen
Hydrogen is the chemical element with the symbol H and atomic number 1. Hydrogen is the lightest element. At standard conditions hydrogen is a gas of diatomic molecules having the formula . It is colorless, odorless, tasteless, non-toxic, an ...
, among other elements (1862), and in 1868 he published his great map of the normal
solar spectrum in ''Recherches sur le spectre solaire'', including detailed measurements of more than 1000
spectral line
A spectral line is a dark or bright line in an otherwise uniform and continuous spectrum, resulting from emission or absorption of light in a narrow frequency range, compared with the nearby frequencies. Spectral lines are often used to iden ...
s, which long remained authoritative in questions of wavelength, although his measurements were inexact by one part in 7000 or 8000, owing to the metre he used as a standard being slightly too short.
![Recherches sur le spectre solaire](https://upload.wikimedia.org/wikipedia/commons/5/50/Recherches_sur_le_spectre_solaire.jpg)
He was the first, in 1867, to examine the spectrum of the
aurora borealis
An aurora (plural: auroras or aurorae), also commonly known as the polar lights, is a natural light display in Earth's sky, predominantly seen in high-latitude regions (around the Arctic and Antarctic). Auroras display dynamic patterns of br ...
, and detected and measured the characteristic bright line in its yellow-green region; but he was mistaken in supposing that this same line, which is often called by his name, is also to be seen in the
zodiacal light
The zodiacal light (also called false dawn when seen before sunrise) is a faint glow of diffuse sunlight scattered by interplanetary dust. Brighter around the Sun, it appears in a particularly dark night sky to extend from the Sun's direction in ...
.
He was elected a member of a number of learned societies, including the
Royal Swedish Academy of Sciences
The Royal Swedish Academy of Sciences ( sv, Kungliga Vetenskapsakademien) 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 ...
in 1850, the
Royal Society
The Royal Society, formally The Royal Society of London for Improving Natural Knowledge, is a learned society and the United Kingdom's national academy of sciences. The society fulfils a number of roles: promoting science and its benefits, re ...
in 1870 and the
Institut de France
The (; ) is a French learned society, grouping five , including the Académie Française. It was established in 1795 at the direction of the National Convention. Located on the Quai de Conti in the 6th arrondissement of Paris, the institute m ...
in 1873. He died in Uppsala on 21 June 1874.
His son,
Knut
Knut (Norwegian language, Norwegian and Swedish language, Swedish), Knud (Danish language, Danish), or Knútur (Icelandic) is a Scandinavian, German language, German, and Dutch language, Dutch first name, of which the anglicised form is Canute. ...
(1857–1910), was also a physicist.
Honours
The
Ångström
The angstromEntry "angstrom" in the Oxford online dictionary. Retrieved on 2019-03-02 from https://en.oxforddictionaries.com/definition/angstrom.Entry "angstrom" in the Merriam-Webster online dictionary. Retrieved on 2019-03-02 from https://www.m ...
unit (1 Ã… = 10
−10 m) in which the
wavelength
In physics, the wavelength is the spatial period of a periodic wave—the distance over which the wave's shape repeats.
It is the distance between consecutive corresponding points of the same phase on the wave, such as two adjacent crests, tro ...
s of light and interatomic spacings in condensed matter are sometimes measured is named after him.
The unit is also used in
crystallography
Crystallography is the experimental science of determining the arrangement of atoms in crystalline solids. Crystallography is a fundamental subject in the fields of materials science and solid-state physics (condensed matter physics). The wor ...
as well as spectroscopy.
The crater
Ångström
The angstromEntry "angstrom" in the Oxford online dictionary. Retrieved on 2019-03-02 from https://en.oxforddictionaries.com/definition/angstrom.Entry "angstrom" in the Merriam-Webster online dictionary. Retrieved on 2019-03-02 from https://www.m ...
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 of ...
is named in his honour.
One of the main building complexes of
Uppsala University
Uppsala University ( sv, Uppsala universitet) 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 opera ...
, the Ångström Laboratory, is named in his honour. This building houses various departments including the Department of Physics and Astronomy, Department of Mathematics, Department of Engineering Sciences, Institute of Space Physics, and the Department of Chemistry.
Death
Anders Ångström died in June 1874 from meningitis, shortly before his sixtieth birthday.
See also
*
Johann Balmer
Johann Jakob Balmer (1 May 1825 – 12 March 1898) was a Swiss mathematician best known for his work in physics, the Balmer series of hydrogen atom.
Biography
Balmer was born in Lausen, Switzerland, the son of a chief justice also named Johan ...
*
Gustav Kirchhoff
Gustav Robert Kirchhoff (; 12 March 1824 – 17 October 1887) was a German physicist who contributed to the fundamental understanding of electrical circuits, spectroscopy, and the emission of black-body radiation by heated objects.
He ...
*
Theodore Lyman Theodore Lyman may refer to:
* Theodore B. Lyman (1815–1893), American bishop
* Theodore Lyman II (1792–1849), American philanthropist, politician, and author
* Theodore Lyman III (1833–1897), American natural scientist, military staff offic ...
*
Friedrich Paschen
Louis Carl Heinrich Friedrich Paschen (22 January 1865 - 25 February 1947), was a German physicist, known for his work on electrical discharges. He is also known for the Paschen series, a series of hydrogen spectral lines in the infrared region t ...
*
Janne Rydberg
*
Spectrum analysis
References
Further reading
*
External links
*
{{DEFAULTSORT:Angstrom, Anders Jonas
1814 births
1874 deaths
Foreign Members of the Royal Society
Members of the French Academy of Sciences
Members of the Royal Swedish Academy of Sciences
People from Timrå Municipality
19th-century Swedish astronomers
19th-century Swedish physicists
Uppsala University alumni
Spectroscopists
Burials at Uppsala old cemetery
Members of the Royal Society of Sciences in Uppsala