 Firstly, we have Sanches’ view of comets, more or less derived from Aristotle’s notions of the heavens and the place of comets within them. For Aristotle comets were celestial bodies inhabiting the space between the Earth and the upper heavenly spheres. They were created by hot dry exhalation that emanated from the terrestrial sphere, and clashed, as it were, with the movement of the heavenly sphere (Meteorologica 344a8–33); or as Aristotle explained: if the exhalation extended in all directions it was called a “comet or long-haired star”, and if it extended lengthwise only it was called a “bearded star”. 