Space operas are science fiction.

I have a pretty inclusive definition of science fiction. If it has advanced technology--doesn't matter if it's actually possible--it's sci-fi. Doesn't matter if there's The Force, magic, or whatever on top of that; it's still science fiction, but, if that's the case, it's also science fantasy.

I consider superhero stuff to be sci-fi--at least those whose fantastical elements aren't magic.
Superman can fly because he's Kryptonian? Sci-fi. G'vorn the Terrible can fly because he's a sorcerer? Fantasy.

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If we don't play god, who will?-James Watson
I never think of the future, it comes soon enough.-Albert Einstein
The large print giveth and the small print taketh away.-Tom Waits
Any sufficiently advanced technology is indistinguishable from a yo-yo.-Enoch Root, The Confusion
When I was a kid, if someone brandished a shrink gun he'd get a little bit of respect!-Myron Reducto, Harvey Birdman