Hmm: not 'most' people, but certainly some. Yes, but that is all they say. They don't say which countries or languages use
Nova as a male name, they don't say either if it's a full name or a nickname, perhaps for Novalis, or a version of
Noah(!), and they could also usefully say how old these male Novas are. If they're all, say, 14 years old, then we should be looking for a commercial event that inspired their parents - a movie, a band, a new icecream ... But if they come in all ages, then it's a different situation.
So, any more information that you can give will be very useful, and this board is a good place to start.