It is hard to imagine what our level of scientific understanding of the modern world would be like without Rutherford's pioneering discoveries that, in the course of radioactive decay, elements are transformed into different chemical species and that this phenomenon can be explained by the existence of the 'nuclear' atom. At the time these concepts were so original and 'outside the box' that Rutherford and his select band of collaborators were taking the first tentative steps in exploring what was then completely unknown and unchartered territory. An analogy is, perhaps, the recent Rosetta mission to characterize a comet, where the numerous international investigating teams were faced with the totally unexpected observations which only became apparent as this grand-scale experiment progressed.
Starting with an account of his early life and career progression, this talk will look at Rutherford's principal achievements as set against the background of relevant scientific knowledge of the time. A brief survey will then be given of certain aspects of the Rosetta mission (in which the speaker played a relatively minor role) as a means of comparing and contrasting various features of these two rather different examples of scientific exploration.