To answer the original question, i.e.,

Quote -
If aliens exist and they don't accept Jesus Christ as their savior, will they go to hell?

No, because there is no hell. No heaven either.
While the man known popularly as Jesus Christ may have existed, and while he was likely an exceptional figure, he was nothing more than a teacher and a "missionary" of sorts. An exceptionally intelligent and brave teacher no doubt, but very human and there was nothing godlike or metaphysical about him.

No salvation, no Creator, no messiah... just space, matter, energy, chemistry and the laws of physics that all eventually led to an intelligence so consumed with its own self-importance that it invented gods, heaven and salvation to ease its troubled mind and make its existence more bearable...

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