History of Solar System formation and evolution hypotheses moon and Mercury was a moon of Venus but drifted away because of the Sun's gravitational influence. Mars was a moon of Bellatrix. One major argument against exploding planets and moons is that there would not be an energy source powerful enough to cause such explosions. In J. Marvin Herndon's model, inner (large-core) planets form by condensation and raining-out from within giant gaseous protoplanets at high pressures and high temperatures. Earth's complete condensation included a c. 300 Earth-mass gas/ice shell that compressed the rocky kernel to about 66% of Earth's present diameter (Jupiter equates to about 300 Earth masses, which
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