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
Egdon Heath (Holst) Holst considered the work his most perfectly realised composition, an opinion shared by Ralph Vaughan Williams and others. But it has never had the profile of works such as "The Planets" and "St Paul's Suite". In 1934 Edwin Evans speculated on why the public had not yet shared the composer's assessment: Egdon Heath (Holst) Egdon Heath, Op. 47, H. 172, subtitled "A Homage to Thomas Hardy", is a tone poem by Gustav Holst, written in 1927. Holst considered it his most perfectly realised composition. Egdon Heath is a fictional place in the equally fictional region of Wessex in the south-west