Based on extensive primary sources, including many documents from Olbers, Gauss, Zach, and Regner never previously translated into English, this is the definitive account of the origins of Juno and Vesta by Hershel. Primary sources about the discovery are included in new translations, including personal correspondence and scientific papers. Cunningham, a dedicated scholar of asteroids, opens to scrutiny this critical moment of astronomical discovery, continuing the story begun in Volumes I, II and III of this series. The discovery of this new class of celestial bodies, as well as the revelation of the existence of the Asteroid Belt, set off an entirely new understanding of the Solar System, the implications of which are thoroughly discussed. How the discovery of Juno influenced Bode in his thinking about “Bode’s Law” is studied, and the volume concludes with a look at the instruments and observatories that analyzed the asteroids in these early years of the nineteenth century.