Discovery in Astronomy: Ex Uno Plures

Abstract

The solitary figure fixes his eye to the telescope, scanning the skies. The sleeves of his robes drag across piled-up volumes as he pores over tattered charts and arcane instruments, seeking the discovery that will catapult him to immortality. This is the kind of image evoked over centuries by the word “astronomer.” Except for the candle, the tableau in Gerrit Dou’s Astronomer by Candlelight, painted 350 years ago,¹ is probably not too far from the popular image, even today. For most of astronomical history, meticulously compiling catalogues of positions and motions in the sky was the primary research activity.