The Ångström family

The Ångström family decends from Anders Persson, a taxed freeholder from Ånge in the Parish of Borgsjö in the county of Medelpad. His son Johan, Preacher at Lögdö Ironworks and later Assistant Vicar in Sätna in Medelpad took the family name Ångström, and his son, Anders Jonas Ångström was later born in Lögdö in 1814. After schooling in Härnösand he came to Uppsala in 1833 where succesful studies led to a Doctors degree in Physics in 1839. However, he did for a start work as an Observator in Astronomy until he became a Professor in Physics in 1858, when at last Physics acquired their own permanent premises.

Anders Jonas Ångström introduced regular laboratory studies for the students. In his research he combined splendied experimental skill with deep knowledge in Mathematics. He was very versatile. Among other things he studied Thermal Conductivity, Heat Theory and Earth Magnetism, but above all he is known as one of the founders of Spectroscopical Science.

He made thorough studies of the Spectrum of the Sun, especially the Fraunhofer lines. The publication "Recherches sur le spectre solaire" from 1868 is known as one of the classical works in Spectroscopy and was normative for a long time. He also was the first to study the Spectrum of the Northern lights. The unit for the wavelength of light was introduced by him and later accepted as an international unit called Ångström (1 å = 0,1 nm).

The son of Anders Jonas Ångström, Knut Ångström (1857-1910) did of course pursue his studies at Uppsala University. After his Licentiate degree in 1884 he went to Strassbourg and stayed with August Kundt which led to a Doctors degree and lectureship in Uppsala in 1885. He served for a few years at the College of Stockholm where he contributed well in the planning and organizing of their Department of Physics. In 1891 he returned to Uppsala as an Associate Professor in Physics and was eventually offered his professorship in 1896. He carried out research in Heat and Solar Radiation and foremost in the so-called Solar constant. During 1895-1896 in Tenerife, in the Canary Islands, he made a thorough investigation of Solar Radiation measuring the Solar constant. Close to this research he also studied the absorption of Solar radiation within the infrared part of the spectrum caused by water steam, carbion dioxide  and ozone. Knut Ångström was an eminent constructor of instruments, and his Pyrheliometer for direct measuring of the incoming solar radiation was accepted as official standard in 1905. The instrument has later been modified ans is still used as reference. Knut Ångström also enforced the building of a new well organized Department of Physics that was officially opened in 1908 in Uppsala. He was a member of the Nobel Committee for Physics in the Academie of Science from the start in 1901, and he was the chairman from 1905.

A detailed description of the scientific achievements of Anders Jonas Ångström and Knut Ångström is published in Acta Universitatis Upsaliensis, writings concerning Uppsala University, C. Organisation och historia, 60. Ångström, far och son, 1997.