Well, you see, I was kind of interested in the premise of "nitpicking the science of the movies" here, as opposed to playing the Trek Logic Excuse-making Game that's carried on in almost every other topic on the board. The latter is something that everyone can do in their sleep by this time, at least to their own satisfaction. So I was wondering if anyone knew of any way that we might possibly actually get such specific data from a Voyager probe that such a conclusion could be reached or whether the statement in the movie is doomed to be only the customary and arbitrary Trek handwavium that it was clearly on the writer's part.
A lot of the "scientific nitpicking" thus far doesn't actually have much to do with either science or technology, though - debating whether the Genesis Device (which is based in neither science nor technology) could create a star and planet based on the parameters established for the thing has nothing to do with either, for example, but is entirely a conversation about the internal story logic of the script and nothing more.

But, if you prefer wanton scientific bullshit, try Insurrection. Not only does it have another nebula-type dust cloud of the silly type, it has a star and a habitable planet with billions of years worth of evolution on it inside it. So it's not even a planetary nebula. It's a bunch of random crap that somehow covers a G-class sun. (And unlike M-class, G-class means something.)
Plus, you have a radiation field causing a reversal of cellular damage? That's about the dumbest thing I've ever heard.