Terrestrial planet from the original solar nebula. The Solar System has four terrestrial planets: Mercury, Venus, Earth, and Mars. Only one terrestrial planet, Earth, is known to have an active hydrosphere. During the formation of the Solar System, there were probably many more terrestrial planetesimals, but most merged with or were ejected by the four terrestrial planets. Dwarf planets, such as Ceres, Pluto and Eris, and small Solar System bodies are similar to terrestrial planets in the fact that they do have a solid surface, but are, on average, composed of more icy materials (Ceres, Pluto and Eris have densities of 2.17,
Gustav Holst compositions. In the "Two Songs without Words" of 1906, Holst showed that he could create his own original music using the folk idiom. An orchestral folksong fantasy "Songs of the West", also written in 1906, was withdrawn by the composer and never published, although it emerged in the 1980s in the form of an arrangement for wind band by James Curnow. In the years before the First World War, Holst composed in a variety of genres. Matthews considers the evocation of a North African town in the "Beni Mora" suite of 1908 the composer's most individual work to that date;