Terrestrial planet Terrestrial planet A terrestrial planet, telluric planet, or rocky planet is a planet that is composed primarily of silicate rocks or metals. Within the Solar System, the terrestrial planets are the inner planets closest to the Sun, i.e. Mercury, Venus, Earth, and Mars. The terms "terrestrial planet" and "telluric planet" are derived from Latin words for Earth ("Terra" and "Tellus"), as these planets are, in terms of structure, "Earth-like". Terrestrial planets have a solid planetary surface, making them substantially different from the larger giant planets, which are composed mostly of some combination of hydrogen, helium, and water existing in various
Gustav Holst found his genuine voice in his setting of Whitman's verses, "The Mystic Trumpeter" (1904), in which the trumpet calls that characterise Mars in "The Planets" are briefly anticipated. In this work, Holst first employs the technique of bitonality—the use of two keys simultaneously. At the beginning of the 20th century, according to Matthews, it appeared that Holst might follow Schoenberg into late Romanticism. Instead, as Holst recognised afterwards, his encounter with Purcell's "Dido and Aeneas" prompted his searching for a "musical idiom of the English language"; the folksong revival became a further catalyst for Holst to seek inspiration from other