But ... that's what "anomaly" means -- a failure of unknown origin. It's just a concise way of saying it.
> Calling it an "anomaly" strongly implies that there was some sort of unexpected natural phenomena to blame ...
No, the word "anomaly", at least as used in space science, doesn't suggest that at all. In this context, anomaly means what idiopathic means in medicine -- an outcome of unknown origin.
No it doesn't. You should really look up the definition of the word, because you'll find it's being used correctly.
I can't resist adding that I've always described this quote in just this way (as do others), but it's never far from my mind that it relies on an English idiom, one in which "fix" has two meanings. It's not the same in Japanese.