New evidence points toward Ninth Planet in the solar system

[Jackalope]

That's true; but I specifically stipluated reasons of tradition, rather than strict scientific accuracy. Basically the same sort of reason that The Plough is recognised as an entity in its own right, despite its more accurate status as an asterism of Ursa Major.

The IANA cares more about rational classifications than tradition - and I'm pretty sure they don't recognize The Plough / Big Dipper at all. AFAIK, they don't name asterisms.