Sol IX

[Drashner1]

The object, which the researchers have nicknamed Planet Nine, has a mass about 10 times that of Earth and orbits about 20 times farther from the sun on average than does Neptune (which orbits the sun at an average distance of 2.8 billion miles). In fact, it would take this new planet between 10,000 and 20,000 years to make just one full orbit around the sun.

For comparison, Uranus has ~14.54 M⊕. The estimated orbital period is like taking Neptune's orbital period of ~165 standard years and boosting it two orders of magnitude higher.

The thing that immediately comes to mind for me on the way this might have an effect on the OAU is that Solsys wormholes around our new-and-updated Solsys would have to be placed further than pre-P9 Solsys wormholes. The Sothis Bridge and the Einstein Bridge wormholes will have to have a larger minimal safe distance from Sol (not that they were given any description in the first place).

Not necessarily. Remember just how massive OA wormholes are. To provide some numbers:

Mass of Earth = 5.97e24kg

Mass of Sol IX = ~5.97e25kg

Mass of S4 WH (100m radius) = 1.369e26kg

Mass of S5 WH (1000m radius) = 1.369e25kg

The Einstein Gate is described as having started out at 450m radius (and almost certainly predates the appearance of S5s, although S5 tech might have been used in later centuries to upgrade and modernize it) and by Y11k is at 5000m radius.

The scalar field generators used to expand wormholes convert matter to energy and then use it to generate the fields to expand the wormhole. That mass has to come from somewhere.

Basically, if this planet exists, it would likely have been one of the first things consumed to expand Sol's first WH. Along with perhaps another large number of smaller bodies as well. This would have the added benefit of thinning/clearing out local space around the wormholes to help with navigation and remove potential threats to the asymptotic flatness around the WHs.

Waste not, want not and all that

Todd