2016 schedule

Sat 11:30-12:00
Theatre 106

Discovering Southern double stars - the 20th century

Ross Gould

Canberra Astronomical Society

The Southern Hemisphere was systematically surveyed for double stars later than the Northern Hemisphere. I will look at the work of Innes, Hussey, van den Bos, Rossiter, Voute and others, the emphasis being on the work done in South Africa. The era covered will be from the 1890s to the 1960s. The purpose of searching for doubles is to find the gravitationally bound pairs, the genuine binaries, for establishing over time the orbits and thereby the stellar masses of these objects, and to provide statistical information regarding double and hierarchical systems. As Dr Paul Couteau of Nice Observatory (Fr) has pointed out, by the time the surveys had concluded, more close pairs - the ones most likely to be gravitationally bound - were known in the South than in the North.