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 in such a role. He formally changed "von Holst" to "Holst" by deed poll in September 1918. He was appointed as the YMCA's musical organiser for the Near East, based in Salonica. Holst was given a spectacular send-off. The conductor Adrian Boult recalled, "Just before the Armistice, Gustav Holst burst into my office: 'Adrian, the YMCA are sending me to Salonica quite soon and Balfour Gardiner, bless his heart, has given me a parting present consisting of the Queen's Hall, full of the Queen's Hall Orchestra for the whole of a Sunday morning. So we're going to do "The Planets",