Written in 2008:
http://www.holoscience.com/news.php?article=7y7d3dn5&keywords=solar%20system#dest>> An artist’s impression of the solar nebula. Credit: NASA
However, all is not as it seems. There are objections to the nebular disk accretion model that should be considered fatal were it not for the fact that no alternative seems possible — given the gravity-driven view of the universe. For example, a slowly rotating cloud may tend to collapse under gravity but a point is quickly reached where the outward rotational force counteracts further collapse. Rotational energy must be dissipated somehow to enable the cloud to collapse more. Assuming you manage to form the Sun inside a disk another serious difficulty arises. Gravitational interactions with the disk cause protoplanets to swiftly spiral into the star. Then there is the problem that the Sun, as the most collapsed object, should be spinning the fastest (like a pirouetting dancer pulling in her arms). But the Sun spins slowly. Almost the entire angular momentum in the solar system is to be found in the orbiting planets. And the Sun’s equator is tilted 7 degrees to the plane of the orbiting planets!
Instead of the expected gradation of properties of the planets with distance from the Sun, we find a ‘fruit salad’ of characteristics, which don’t make any sense in the simple nebular model. For example, the Earth has an abundance of water, yet the region where early Earth formed was too hot for water to be incorporated into a solid body. So, in ad hoc fashion, meteorites had to deliver it later. As one expert on the subject remarked, “you need to make a special case for each planet.” Gravitational accretion of planets from a dusty disk doesn’t work anyway—once a disk, always a disk—look at Saturn’s rings. Theory shows it is hard for a planetesimal to get to 1 km in size. But then to avoid fragmentation by collision, a body needs to be 1000 km to provide enough gravity to retain collision debris!
Special requirements abound in the accretion disk model. Even if we assume, despite the objections above, that planets the size of Jupiter can form, we then need a violent phase of activity from the new Sun at just the right time to dissipate most of the matter of the disk while leaving the gas giants with thick atmospheres. But then, how do we explain Jupiter’s three times the solar abundance of noble gases?