Transcript: Several hundred years ago the astronomer J. Bode noticed a peculiar thing about the spacings and distances of the planets from the Sun. If, for example, you take a sequence of numbers that double, add four to each one and divide by ten you end up almost exactly predicting the distances of the planets from the Sun in units of astronomical units, the Earth-Sun distance. You can see this from the sequence of distances quoted in astronomical units: Mercury at 0.4 AU, Venus at 0.7, Earth at 1.0, Mars at 1.5, then the asteroid belt at 2.8, Jupiter at 5.2, Saturn 9.5, Uranus 19.2, and Pluto at 39.4. This is roughly a sequence of doubling distance. The only planet that doesn’t fit is Neptune, and of course the asteroid belt is not a planet. This peculiar spacing or regularity in the distances of the planets from the Sun is not explained by Newton's law of gravity, but must somehow be to do with the way that the planets formed out of the solar nebula.