9 Nov 2016

According to a group of researchers from the Laboratoire d'astrophysique de Bordeaux, the way the solar system is currently laid out is down to the wobbly behaviour of the gassy giant. It's chaotic orbit, along with that of Saturn, may have created an imbalance in the architecture of the skies, dragging asteroids into the big solar system family

Chaotic architecture, all Jupiter's fault. A group of researchers believe that the way the solar system is laid out, which has puzzled scientists for decades, could be down to the wobbly orbits of the gassy giant and its colleague Saturn. Our corner of the skies is occupied by two families of planets, separated by an asteroid belt: the terrestrials with Mercury, Venus, Mars and of course Earth, and the large worlds of gas and ice, beyond which the Kuiper belt begins.
However, the astronomical figures don't add up. Mars is in an unexpected position and its size - 10% of Earth's mass - should make it an embryo rather than a finished planet. Traditional theories state that at the dawn of the solar system, Jupiter was closer to the sun, “stealing” local mass available for Mars, before migrating to its current position.

This would also explain the inclination, excitement and the presence of water in the asteroid belt. Alternatively, the balances could have been affected by the disk's microphysics: the primordial lumps of matter accumulated in two separate zones, an internal area for terrestrial planets and the rest beyond Jupiter.
However, the authors of the research believe that Mars' peculiarities are primordial and the behaviour of the asteroids was linked to the movements of Jupiter and Saturn. This would mean that the planets were created more or less where they are today, but that their orbits, which are stable yet wobbly, dragged some of the external asteroids closer in.