History of Solar System formation and evolution hypotheses (we've known, of course, since 1965, that it doesn't), very slow, accelerated, and finally, daily rotation. He explained the differences between inner and outer planets and inner and outer moons through vortex behaviour. Mercury's eccentric orbit was explained by its recent expulsion from the Sun and Venus' slow rotation as its being in the "slow rotation phase", having been expelled second to last. The Tom Van Flandern model was first proposed in 1993 in the first edition of his book. In the revised version from 1999 and later, the original Solar System had 6 pairs of twin planets each fissioned
Climate of Uranus radiates hardly any excess heat at all. The total power radiated by Uranus in the far infrared (i.e. heat) part of the spectrum is times the solar energy absorbed in its atmosphere. In fact, Uranus's heat flux is only W/m², which is lower than the internal heat flux of Earth of about 0.075 W/m². The lowest temperature recorded in Uranus's tropopause is 49 K (−224 °C), making Uranus the coldest planet in the Solar System, colder than Neptune. Another hypothesis states that when Uranus was "knocked over" by the supermassive impactor which caused its extreme axial tilt, the event also