ESHS/HSS Annual Meeting

Telegraphing Astronomical Intelligence

• In Event: Celestial Spheres

English Abstract

In computing his 1887 eclipse catalog through the year 2161 CE, Theodor Oppolzer omitted solar eclipse visibility maps for the southern hemisphere, implicitly dismissing the possibility of astronomers at work in Santiago, Sydney, the Cape of Good Hope, and other points further south. Astronomers’ growing use of telegraphy in the latter half of the nineteenth century, however, made the work of observers around the world potentially critical to the discovery of celestial phenomena. In 1931, the Astronomical Society of the Pacific awarded one of its annual medals for newly discovered comets to Percy Mayow Ryves, who first sighted the phenomenon from Zarazoga, Spain. Ryves telegraphed his discovery to the International Astronomical Union’s Central Astronomical Bureau (Copenhagen), which photographed the object the following morning and retransmitted initial observations by postcard. Confirmation of Ryves’ comet as “new and unexpected” depended on an international community networked from Wisconsin to Kyoto via an ecosystem of astronomical intelligence: newspapers, journals, circulars, letters, and, most expeditiously, telegrams—a relatively new mode of communication whose celerity alerted astronomers to look for celestial objects whose visibility for earth-bound observers was location-dependent and fleeting. The intelligibility of telegraphed astronomical information, however, proved maddeningly elusive. Ryves’ discovery telegram had arrived in Copenhagen “given in a Code unknown here.” At least three major systems for encoding astronomical data by telegram competed for international consensus from the latter half of the nineteenth century onwards. This paper explores the epistemic challenges of telegraphed astronomical intelligence and its consequences for international scientific collaboration.

Author

• Florence C Hsia, University of Wisconsin–Madison