Piazzi’s discoveries were not published until the autumn of 1801. The possible
discovery—and subsequent loss—of a new planet, coinciding with the beginning
of a new century, was exciting news. It contradicted a philosophical justification
for the existence of only seven planets—the number known before Ceres and a
number defended by the respected philosopher Georg Hegel, among others. Hegel
had recently published a book in which he chastised the astronomers for wasting
their time searching for an eighth planet when there was sound philosophical justification
for there being only seven. The new celestial object became a subject of