EPS Historic Site in Heidelberg: The birthplace of spectral analysis
This article by Alexander Pawlak is a publication of the Physik Journal 11/2018 and can be found here.
The former laboratories of Gustav Robert Kirchhoff and Robert Wilhelm Bunsen in Heidelberg have been distinguished as an EPS Historic Site.
Spectral analysis has an enormous range of applications from the classical chemical analysis of substances, for example in industry, medicine or forensics, to the observation of spectra in astro- and atomic physics, to applications for basic physics or metrology.
To visit the place where this method was developed, walk the old town of Heidelberg, where you will find the Haus zum Riesen (House of the Giant), built in 1707 at Hauptstraße 52. From 1859 to 1863, Gustav Robert Kirchhoff (1824-1887) and Robert Wilhelm Bunsen (1811-1899) jointly researched the spectral analysis of chemical elements in the neighbourhood of this impressive building, which today houses the Institute for Translation and Interpreting (IÜD) of Heidelberg University.
On October 1st, the former laboratories of Kirchhoff and Bunsen were distinguished as an “Historic Site” of the European Physical Society. A stele of the EPS was unveiled in the inner courtyard of the IÜD. In the preceding ceremony, representatives of EPS, the German Physical Society (DPG) and the University paid tribute to the life and work of Bunsen and Kirchhoff. In his lecture, Karlheinz Meier (1955 – 2018) from the Kirchhoff-Institute for Physics at the University Heidelberg gave a fascinating overview of the lives and works of Bunsen and Kirchhoff.
In 1850, Bunsen had accepted an appointment at the University of Breslau (today Wrocław), where he met the 13-year younger physicist Kirchhoff. Both scientists quickly made friends. After three semesters in Breslau, Bunsen moved to the University of Heidelberg, where one of the most modern chemical laboratories of the time was set up. In 1854, Kirchhoff also moved to Heidelberg. Bunsen had supported his appointment.
A fruitful cooperation soon developed in Heidelberg. From 1857 to 1863, Kirchhoff and Bunsen published numerous papers on thermal radiation and spectral analysis, either individually or together. They systematically investigated the spectra of earth substances and discovered, among other things, the elements Caesium and Rubidium in the salts of the Maxquelle in Bad Dürkheim. An analysis of the solar spectrum showed for the first time that stars also consist of the known terrestrial elements. The work of Kirchhoff and Bunsen formed a basis for quantum physics; the interpretation of the solar spectrum marks the birth of astrophysics as a quantitative science.
The laboratories of Bunsen and Kirchhoff are the 42nd EPS Historic Site. Nearby is the birthplace and private observatory of astronomer Max Wolf (1863-1932), who laid the foundations for astronomical research in Heidelberg.
Other places in Germany which the EPS has honoured for their special significance for the development and history of physics include the Physikalische Bundesanstalt and Reichsanstalt in Berlin and the former Physikalisches Institut in Würzburg, where Wilhelm Röntgen discovered the X-rays.
