The Olympic Competition of Thomas Digges: The measurement of parallax and the development of observational methods in astronomy

A few months after the appearance of the supernova SN1572, Thomas Digges wrote a Latin book entitled Alae seu Scalae Mathematicae… in which he presented new methods for measuring small parallax angles like those expected for planets and other objects at similar distances. On the basis of our new translation into English of some sections of this book, we point out several relevant innovations developed by Digges. These concern the accuracy of astronomical measurements and a discussion on the origin of observational and computational errors. Furthermore, Digges introduced a simple but effective method for the falsification of observational results, which was useful for disproving some incorrect claims reported by other observers. It is also clear that Digges is completely disinterested in the astrological implications of this unexpected celestial phenomenon.