Why is our solar system different from most of the others we see? How common are planets like Earth that have life on them? Is there life under the ice of Europa? Why will alien life have similar systems to ours? How did we get homochirality, and more to the point, why? I am uploading an ebook with the above title to Amazon that provides answers, and once they put it up, for five days it is a free download, which I why I am mentioning this here. (The answers to these questions are: accretion disks last between 1-10 My after stellar accretion, and our system is required to be one of the 50% where the disk only lasted ca 1 My; some significant fraction of that 50% around stars of similar size to Sol because life is a consequence of planetary formation; life under Europa is impossible for several reasons, an absence of nitrogen and no mechanism to make phosphate esters being two of them; RNA is the only feasible polymer that can self-reproduce and form abiogenically in dilute aqueous solution; homochirality is a requirement for life and it selects itself, but why is too complicated for such a quick comment.)
 
Why am I putting up an alternative theory as an ebook, instead of through peer-reviewed scientific papers? There are several reasons, including:
(a) The theory is largely chemical, which explains why the various planets and minor bodies have different compositions, but only a few physics journals will publish theories on planetary formation,
(b) Such journals require computer modelling. I can't do that, and in any case the growth of a planet with respect to time requires four terms, none of which have clearly defined values.
(c) Scientific papers really should assert one major point. No single point is convincing, but my argument it that the complete set is.
(d) I want to get it read. So far I have published what I believe are four very significant advances (if correct) in peer-reviewed papers, and I doubt anybody reading this could name one of them.
 
But surely standard theory is adequate, so you say? Then consider this. In standard theory you need a relatively massive amount of solids to form planetesimals (with no known mechanism to form them) which then, in our system, take about 15 My to get to the point where Jupiter can start massive gas accretion. Because of solids dilution with distance, the problem gets much worse with distance. (Originally Safranov required 10^11 yr to form Neptune. Subsequent models have greatly reduced this, but it is not entirely clear to me how, or, putting it another way, why was Safranov so wrong?) However, there is a planet LkCa 15b that is about three times Jupiter's distance from a star slightly smaller than Sol, it is about 5 times Jupiter's mass, and LkCa is a ca 2 My star. (Which is why I believe our system removed its accretion disk early.) If you are interested the download, at http://www.amazon.com/dp/B007T0QE6I is free from April 12-16, which is why I am putting it on this post. I know there should be no commercial point to these posts, but free seems to me to be different.