Can I be a professional ballet dancer with less than perfect turnout?

First off turnout is properly expressed as 90 degrees coming from each hip and not 180 degrees as that is where your feet not hips are. That being said while 90 degrees is ideal, 70 degrees is way off the mark for a professional ballet career. I have seen dancers with as little as only 85 degrees from each hip do this but not less than that. All of ballet comes from your turnout and if this is all you have, realistically this is just not going to happen for you. You will not get into the schools that have professional training as you will be cut during auditions due to this. That means the only training available to you will be recreational training even if your current school has what they call a "pre-professional division," Calling it that doesn't really make it so.

I know it isn't fair, but that is how it is in professional ballet. You have to be born with the body, facility and musicality required for a ballet career and turnout is of paramount importance. Your body is your instrument. Without the right instrument this just wont happen for you.

I suggest you either just enjoy your ballet classes because no where is it written you have to be a professional ballet dancer in order to do this. If you are open to another type of dance career such as in modern/contemporary dance, full turnout is not a requirement and that may still be a possibility for you if you get the right training and have the rest of the right gifts required.