New star sign

I see how it's spelled, how it's pronouncd is probably a better description.

It’s pronounced ‘Oh few kuss’.

It’s not a Zodiac sign as such, but a star constellation.
I’m a Sagittarian and fall within its dates, of Nov 29th to Dec 17th, but I shall remain a Sagittarian.

The short answer to why the constellation Ophiuchus isn't an astrological sign is that people are probably not going to stop using the traditional astrological calendar with which we're all familiar.
That said horoscopes are bunkum, why would some celestial objects trillions of miles away determine your demeanour, your characteristics and your future lifestyle.

If they fall on your head, they will determine your outcome?