1-158-562 - Oxford Science Archive/Heritage Images

Obverse of a medal commemorating the bright comet of 1577. Known as Brahe's comet, this is the comet which convinced the Danish astronomer Tycho Brahe (1546-1601) that there is change beyond the sphere of the Moon. It is shown in his system of the universe published in his Mundi aetherei recentioribus Phaenomensis (1589).