Eclipsed but not forgotten: two lesser-known Australian expeditions to the 1922 total solar eclipse

When the centenary of the 1922 eclipse was celebrated in 2022, the focus was the absolute proof of Einstein’s theory of General Relativity achieved at Wallal in Western Australia by the Crocker expedition that had been led by William Campbell, the director of the Lick Observatory in California. This paper provides case studies of two lesser-known 1922 expeditions. The first case study is the Adelaide Observatory expedition to a remote sheep station called Cordillo Downs, located near the north-east corner of South Australia. This was the base for the expedition organised by South Australian Government Astronomer, George Dodwell. The second case study is that of the University of Sydney’s expedition to Goondiwindi in southern Queensland, organised by physics professor Oscar Ulrich Vonwiller under the auspices of New South Wales Government Astronomer, William Ernest Cooke. We examine how Adelaide Observatory and the University of Sydney prepared for the eclipse, organised instrument loans and brought together, and relied upon, people with different expertise, including First Nations people and two women scientists. Despite limited resources, preparation time and only minutes in which to perform total eclipse experiments and make observations, there were both successes and failures. We reveal British influence and the extent of the Australian Government’s involvement via a Commonwealth Eclipse Committee–one of the unique aspects of this eclipse. As well as referring to photographs and archival documents, this paper examines the instruments each party used and the glass plate negatives taken at Cordillo Downs to test General Relativity, and where they are now located.