Anders Jonas Angstrom – Biography of Anders Jonas Angstrom

The Swedish physicist Anders Jonas Angstrom He was born in the city of Lögdö, on August 13, 1814. Today he is remembered as one of the founders of the science of spectroscopy.

In 1843, at only 29 years old, he was appointed director of the Astronomical Observatory of the city of Uppsala; in 1858, in the same city he became a professor of physics.

Angstrom He is famous in the field of science for his research on magnetism, heat and optics, but especially for the study of the phenomenon of the northern lights.

The Swedish scientist proved in 1862 that the Sun’s atmosphere contains hydrogen: for this he used a combination of spectroscopy and photography.

He published his in-depth research on the solar spectrum in “Recherches sur le specter solaire“(1868), which includes detailed measurements of more than a thousand spectral lines.

In a paper presented at the Stockholm Academy in 1853, he not only demonstrated that the electric spark produces two superimposed spectra, one for the metal electrode and the other for the passing gas, but he also deduced from Euler’s resonance theory , that an incandescent gas emits light rays of the same refractive capacity as that which they can absorb.

This statement contains a fundamental principle of spectral analysis: although its studies have been neglected for several years, science today is unanimous in including Angstrom among the founders of the spectroscopy.
For these studies he received the Rumford medal from the Royal Society in 1872.

Angstrom He was the first physicist to examine the spectrum of the Northern Lights (in 1867): he individualized it, by measuring it, in the characteristic bright line of the yellow-green region.

In recognition of his contributions to spectroscopy the unit wavelengths of the lines are defined Ångström: (1 Å = 0.1 nm).
This unit is used in both crystallography and spectroscopy.
Anders Jonas Angstrom He died shortly before his 60th birthday, in Uppsala, on June 21, 1874.

His son, Knut Ångström (1857-1910), was known for his research at Uppsala University on solar radiation, heat radiation from the sun, and its absorption by the Earth’s atmosphere.

For his research, Knut devised different delicate methods and instruments, including the electrically compensated pyrheliometer, invented in 1893, and an apparatus for obtaining a photographic representation of the infrared spectrum, in 1895.