[scrabblehack]

I asked about Bode’s Law when they discovered Xena, was it?
The response was that the first few planets lined up with Bode’s Law was just due to a coincidence.

[SunkenCiv]

That may have been me, but in any case, that is my view. :') If the planetary masses were uniformly smaller (or larger) the farther out one went, then there could be some kind of stable and uniform distribution (1,2,3,4, or 1,2,4,8, or whatever) of the planets. But there isn't. The so-called Kuiper Cliff is viewed as suggestive of such a planet as JK writes about. However, his 77+ AU primordial world seems a bit unlikely:

Planet X
by David Jewitt

What this means is that a planet of Earth's mass could exist undetected if it were more than a few 100 AU away, and even a Jupiter (300 Earth mass planet) could exist at distances only slightly greater. The sun could have a companion brown dwarf or even a star if far enough away! It's a nice thought but it will be very tough to do anything about it unless we are lucky. The Pan STARRS telescope now under development in Hawaii will provide the best constraints in the forseeable future. Will we get lucky? Stay tuned to find out.

Since it hasn't been detected, it would have to be A) really dark, B) really far out (the gap would then be a consequence of something further out), C)really far out of the ecliptic, D) moving in retrograde, or E) no longer there.

John B. Murray and John Matese were on record in 1999 (and Matese at least ever since) as saying there is a large undiscovered trans-Neptunian body. The X-Planets keyword and blog topic have much more about all these.