Stability of the Solar System is unlikely any of the planets will collide with each other or be ejected from the system in the next few billion years, and the Earth's orbit will be relatively stable. Since Newton's law of gravitation (1687), mathematicians and astronomers (such as Laplace, Lagrange, Gauss, Poincaré, Kolmogorov, Vladimir Arnold and Jürgen Moser) have searched for evidence for the stability of the planetary motions, and this quest led to many mathematical developments, and several successive 'proofs' of stability of the Solar System. The orbits of the planets are open to long-term variations. Modeling the Solar System is a case of the
Gustav Holst horrors". Nevertheless, the composer and critic Colin Matthews recognises even in these apprentice works an "instinctive orchestral flair". Of the few pieces from this period which demonstrate some originality, Matthews pinpoints the G minor String Trio of 1894 (unperformed until 1974) as the first underivative work produced by Holst. Matthews and Imogen Holst each highlight the "Elegy" movement in "The Cotswold Symphony" (1899–1900) as among the more accomplished of the apprentice works, and Imogen discerns glimpses of her father's real self in the 1899 "Suite de ballet" and the "Ave Maria" of 1900. She and Matthews have asserted that Holst