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 Municipal Orchestra premiered Holst's symphony "The Cotswolds" (Op. 8), the slow movement of which is a lament for William Morris who had died in October 1896, three years before Holst began work on the piece. In 1903 Adolph von Holst died, leaving a small legacy. Holst and his wife decided, as Imogen later put it, that "as they were always hard up the only thing to do was to spend it all at once on a holiday in Germany". While in Germany, Holst reappraised his professional life, and in 1903 he decided to abandon orchestral playing to concentrate on composition.