Unfinished creative work planet Pluto, giving it the name "Pluto, The Renewer". When Holst had written the original piece Pluto had not been discovered, and this addition therefore updated the suite and completed the eight movements that represented the planets of the solar system (Earth was never included) some 80 years after it was originally performed. In August 2006 Pluto was officially demoted to a dwarf planet, meaning that Holst's original work now more accurately represents the solar system. Some extremely famous 20th century operas have been left incomplete at their composers' deaths. Giacomo Puccini left the finale of "Turandot" unfinished and the
Geology of solar terrestrial planets is a region of the Solar System beyond the planets extending from the orbit of Neptune (at 30 AU) to approximately 55 AU from the Sun. It is similar to the asteroid belt, although it is far larger; 20 times as wide and 20–200 times as massive. Like the asteroid belt, it consists mainly of small bodies (remnants from the Solar System's formation) and at least one dwarf planet—Pluto, which may be geologically active. But while the asteroid belt is composed primarily of rock and metal, the Kuiper belt is composed largely of ices, such as methane, ammonia, and water.