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,
The Planets mysterious and distant as Neptune. Holst then scored the suite for a large orchestra, in which form it became enormously popular. Holst's use of orchestration was very imaginative and colourful, showing the influence of such contemporary composers as Igor Stravinsky and Arnold Schoenberg, as well as such late Russian romantics as Nikolai Rimsky-Korsakov and Alexander Glazunov. Its novel sonorities helped make the work an immediate success with audiences at home and abroad. Although "The Planets" remains Holst's most popular work, the composer himself did not count it among his best creations and later in life complained that its popularity had