HOW THE FIRST DWARF PLANET BECAME THE ASTEROID CERES

Abstract

The discovery on 1 January 1801 of an object between Mars and Jupiter was the most remarkable astronomical discovery since the planet Uranus had been found in 1781. Its discoverer, Giuseppe Piazzi at Palermo Observatory in Sicily, was quick to name it Ceres Ferdinandea. But the discovery was considered so important that it sparked national rivalries. In Germany, the much anticipated planet had been dubbed Hera sixteen years previously, and other Germans quickly gave it their own names. Some leading French astronomers soundly rejected Ceres Ferdinandea, preferring to call it Piazzi, while others in Paris accepted the name Ceres, while at the same time objecting to Ferdinandea. Once another ‘planet’ dubbed Pallas was discovered in 1802, William Herschel realised that astronomers were dealing with a new class of object. He was uncertain what name should be employed however, so he canvassed his friends and colleagues for suggestions. Not content with the often ludicrous ideasput forward, he coined the word asteroid. This paper reveals these dual nomenclature issues through previously unpublished private letters, an Italian journal, and the much more sedate language used in printed journals.