SOURCE: "In Defense of Tycho Brahe," in Archive for History of Exact Sciences, Vol. 24, 1981, pp. 257-65.

In the following essay, Rosen argues that Brahe was not the annotator of the Prague copy of Nicolaus Copernicus's De revolutionibus, as some have contended.

Nicholas Copernicus ' On the Revolutions of the Heavenly Spheres, in Six Books (Basel Edition) with Annotations Written by the Hand of Tycho Brahe¹ was published in facsimile (Prague, 1971), as volume XVI, Editio cimelia Bohemica (cited hereafter as "Cimelia"). On Cimelia's title page an unidentified hand wrote: "Property of the Imperial College of the Society of Jesus in Prague, in the year 1642."² The same hand added, just below: "From the Library and Scrutiny of Tycho."³ On the flyleaf preceding the title page a dif ferent hand pointed out: "Observe: There are present marginal notes written by Tycho Brahe's own hand."⁴ At the top of this flyleaf a...