In my (severely neglected) inbox this morning, I have an email from a journalist asking about "planet Y" which means I probably have to sit down and read the latest totally-not-Planet-9 paper, written by a lead author who sets off alarm bells for me because they wrote a bunch of the `Oumuamua-is-totally-an-alien-spaceship papers with That Attention-Seeking Harvard Prof.
Vague enough for you? I need more caffeine.
Without a Planet 9 we cannot have a Planet 10, and thus the Red Lectroids can't get to us by way of the Eighth Dimension. So it's probably just as well.