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 and you've got to conduct'." There was a burst of activity to get things ready in time. The girls at St Paul's helped to copy out the orchestral parts, and the women of Morley and the St Paul's girls learned the choral part in the last movement. The performance was given on 29 September to an invited audience including Sir Henry Wood and most of the professional musicians in London. Five months later, when Holst was in Greece, Boult introduced "The Planets" to the general public, at a concert in February 1919; Holst sent him a long letter full of