The Planets dedication notwithstanding, Imogen Holst "would have been both amused and dismayed by the venture." On 24 August 2006, the International Astronomical Union (IAU) defined what it means to be a "planet" within the Solar System. This definition excluded Pluto as a planet and added it as a member of the new category of "dwarf planets", along with Eris and Ceres. Following the IAU decision, Kenyon D. Wilson composed a trombone quintet piece titled "Songs of Distant Earth". The title comes from Arthur C. Clarke's novel of the same name. The composition contains five movements, each named after one of the
Gustav Holst wrath. In 1912 Holst composed two psalm settings, in which he experimented with plainsong; the same year saw the enduringly popular "St Paul's Suite" (a "gay but retrogressive" piece according to Dickinson), and the failure of his large scale orchestral work "Phantastes". Holst conceived the idea of "The Planets" in 1913, partly as a result of his interest in astrology, and also from his determination, despite the failure of "Phantastes", to produce a large-scale orchestral work. The chosen format may have been influenced by Schoenberg's "Fünf Orchesterstücke", and shares something of the aesthetic, Matthews suggests, of Debussy's "Nocturnes" or "La