[TML] Bigass Planet X

[Joshua Bell]

Eris Reddoch wrote:
> Steve Burchett wrote:
>> I remember being taught Bode's Law in my youth. I wonder if it is
>> still valid?
>>
>> http://www.astro.cornell.edu/academics/courses/astro201/bodes_law.htm
>
> Well, I think most of us don't view Bode's Law as a law at
> all. It, more or less, fits the one complete...more or
> less...model of a star system that we have (Sol's), but in
> science one case does not a tread make, much less a law.
> OTOH, Traveller (and most of us) use something like Bode's Law
> to generate our fictional star systems. :)

American Scientist Vol 95 (September-October 2007) has an article "Are 
Planetary Systems Filled to Capacity?" by Steven Soter (available online 
here: 
http://www.americanscientist.org/template/AssetDetail/assetid/55890?fulltext=true) 
It summarizes the latest research in how resonances have affected orbits in 
our system, what orbits are stable, and how other known planetary systems 
are arranged. The short version: nearly every orbit not being cleared out by 
a larger body due to orbital resonance appears to have something in it. It 
includes a prediction by Rory Barnes and Sean N. Raymond that a planet would 
be found in the 55 Cancri system between planets "c" and "d"; such a planet 
("f") was confirmed in November 2007 
(http://en.wikipedia.org/wiki/55_Cancri).

The Wikipedia article on "Titius-Bode Law" 
(http://en.wikipedia.org/wiki/Titius-Bode_law) indicates that for most 
random generated systems you can derive a Titius-Bode-esque rule. That is, 
there will be some arithmetic progression that generally describes the 
orbits, although it won't necessarily match the "law" and hence the "law" 
can't be used for predictions.