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 horrors". Nevertheless, the composer and critic Colin Matthews recognises even in these apprentice works an "instinctive orchestral flair". Of the few pieces from this period which demonstrate some originality, Matthews pinpoints the G minor String Trio of 1894 (unperformed until 1974) as the first underivative work produced by Holst. Matthews and Imogen Holst each highlight the "Elegy" movement in "The Cotswold Symphony" (1899–1900) as among the more accomplished of the apprentice works, and Imogen discerns glimpses of her father's real self in the 1899 "Suite de ballet" and the "Ave Maria" of 1900. She and Matthews have asserted that Holst