Ernst von Rebeur-Paschwitz

Ernst von Rebeur-Paschwitz (9 August 1861 – 1 October 1895) was a German astronomer, geophysicist and seismologist. He is best known for the first recording of teleseism with the use of his sensitive self-registering horizontal pendulums in 1889. He proposed to create an international network of seismological stations. His ideas led to the founding of the International Seismological Association. His father worked as a government officer and Rebeur-Paschwitz had to change schools frequently. He attended the knight academy in Leignitz, as well as high schools in Wroclaw and Frankfurt/Oder. Later Rebeur-Paschwitz studied mathematics and astronomy in Leipzig. After traveling to England and Ireland, he continued studies in Berlin and Geneva, with a one-year break for military service. In 1883, he received his doctorate at the University of Berlin with a dissertation "On the Movement of Comets in Resisting Average" and became an assistant at the Observatory. on 1 October 1895 in Merseburg at the age of 34.

Sensitive horizontal pendulums In 1885, working as an assistant at the University of Karlsruhe, Rebeur-Paschwitz became interested in Friedrich Zöllner’s pendulum. He collaborated with three different manufacturers: the Fecker pendulum in 1886, the Repsold pendulum in 1888, and the Stückrath two-component model in 1894.

Rebeur-Paschwitz installed one of his pendulum in Potsdam and the second one in Wilhelmshaven close to the North Sea. The pendulums designed to measure the horizontal motion of the ground due to supposed lunar tides. On 17 April 1889 he recorded very strong deflections of the vertical axis on both instruments at the time when a strong earthquake occurred near Tokyo in Japan. Even though the shaking of local earthquakes was recorded several times before, this was the first time when the waves of a faraway earthquake had been registered.

This observation marked the change of seismology from a regional to a global science,

International seismological cooperation Rebeur-Paschwitz realized the necessity for international cooperation in the field of seismology, and in 1895 at the International Geographical Congress proposed to install a homogeneous global seismological station network equipped with horizontal pendulums. As a result, Englishman John Milne established network of stations with simply-to-use horizontal pendulums in the British colonies.

Georg C. K. Gerland presented Rebeur-Paschwitz’s ideas at the sixth International Geographic Conference in London in 1895, and organized the first International Conference of Seismology in Strasbourg in 1901. It was the start of international cooperation in seismology and led to the founding two years later of the International Seismological Association (since 1951 the International Association of Seismology and Physics of the Earth’s Interior (IASPEI)).

Medal The Ernst von Rebeur-Paschiwitz Medal is awarded by the German Geophysical Society for outstanding scientific achievements in geophysics. Winners include: 2017 Lev Vinnik, Moscow; 2015 Rongjiang Wang, Potsdam; 2008 Winfried Hanka, Potsdam; 2007 Karl Hinz, Hanover; 2004 Walter Zürn, Schiltach / Karlsruhe.

Publications

Das Horizontalpendel und seine Anwendung zur Beobachtung der absoluten und relativen Richtungs-Aenderungen der Lothlinie: Ergebnisse einiger mit Unterstützung der Königlich Preussischen Akademie der Wissenschaften in den Jahren 1889-1892 auf den Observatorien zu Wilhelmshaven und Potsdam sowie in Puerto Orotava auf Teneriffa ausgeführter Beobachtungsreihen / E. von Rebeur-Paschwitz (in German) Das Horizontalpendel und seine Anwendung zur Beobachtung der absoluten und relativen Richtungs-Aenderungen der Lothlinie : Ergebnisse einiger mit Unterstützung der Königlich Preussischen Akademie der Wissenschaften in den Jahren 1889-1892 auf den Observatorien zu Wilhelmshaven und Potsdam sowie in Puerto Orotava auf Teneriffa ausgeführter Beobachtungsreihen / E. von Rebeur-Paschwitz / Halle : Blochmann, 1892 (in German) Über die Bewegung der Kometen im widerstehenden Mittel, mit besonderer Berücksichtigung der sonnennahen Kometen / Ernst Rebeur-Paschwitz / Berlin : Druck P. Stankiewicz, 1883 (in German) The Earthquake of Tokyo, April 18, 1889. Nature (1889) 40, 1030, 294-295