I do not understand much about astronomy, but about a month ago NASA scientists stated that there could be several planets almost as big as Earth in the Solar system outer borders. Japanese scientists are going to show one of those (though much smaller then Earth). So how it connects with this paper?
And i do not believe in the idea of aliens,invasion and such. Just i was amazed by the issue then and puzzled now.

I'll see you that nail and raise you a Sitchin Crowbar.


no nasa kid is gonna douse this flame baby.

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Hmm, putting one foot in but leaving the other out, just something about this just screams "Wait and see first" We all know how Nasa loves to wait and see what the public will do first before they release anything, Interesting to say nonetheless though.

Unfortunately for our would-be invaders, the L3 point is a weak saddle point

You need to understand something here. The L3 Lagrangian point is one of the "equilibrium" points with respect to Earth, its orbit, and the Sun. The L3 point is the position in Earth's orbit that is directly opposite our planet's own. In other words, the other side of the Sun. Therefore, this article is stating that any mythical planet that was in such a position would move away from the L3 point within 150 years, which basically means that it would have become detectable to Earth based observers a long time ago.

This has nothing whatsoever to do with objects in the outer solar system.