Stability of the Solar System that keeps the far side of the Moon away from the Earth. Mercury is in a 3:2 spin–orbit resonance. The planets' orbits are chaotic over longer timescales, such that the whole Solar System possesses a Lyapunov time in the range of 2–230 million years. In all cases this means that the position of a planet along its orbit ultimately becomes impossible to predict with any certainty (so, for example, the timing of winter and summer become uncertain), but in some cases the orbits themselves may change dramatically. Such chaos manifests most strongly as changes in eccentricity, with some planets' orbits
Gustav Holst Gustav Holst Gustav Theodore Holst (born Gustavus Theodore von Holst; 21 September 1874 – 25 May 1934) was an English composer, arranger and teacher. Best known for his orchestral suite "The Planets", he composed a large number of other works across a range of genres, although none achieved comparable success. His distinctive compositional style was the product of many influences, Richard Wagner and Richard Strauss being most crucial early in his development. The subsequent inspiration of the English folksong revival of the early 20th century, and the example of such rising modern composers as Maurice Ravel, led Holst to develop