Geology of solar terrestrial planets Geology of solar terrestrial planets The geology of solar terrestrial planets mainly deals with the geological aspects of the four terrestrial planets of the Solar System – Mercury, Venus, Earth, and Mars – and one terrestrial dwarf planet: Ceres. Earth is the only terrestrial planet known to have an active hydrosphere. Terrestrial planets are substantially different from the giant planets, which might not have solid surfaces and are composed mostly of some combination of hydrogen, helium, and water existing in various physical states. Terrestrial planets have a compact, rocky surfaces, and Venus, Earth, and Mars each also have an atmosphere.
The Planets: A Modern Allegory The Planets: A Modern Allegory The Planets: A Modern Allegory is a radio play, written in verse, by Alfred Kreymborg. The first performance was on 6 June 1938 by the National Broadcasting Company at the Hayden Planetarium in New York City, and was directed by Thomas L. Riley. The play was originally set to the music of "The Planets" Suite by Gustav Holst; for the first performance the NBC Symphony Orchestra was conducted by H. Leopold Spitalny. The first broadcast was so enthusiastically received that it was repeated a few weeks later. The play describes the early history of the