The long-standing feud between George Takei and William Shatner continues, as the two Star Trek alumni trade barbs over Shatner's recent trip to space.At 90 years old, the former Captain James T. Kirk became the oldest person to ever venture into outer space. However, Takei, who played Hikaru Sulu during his time with Star Trek, was unimpressed by the achievement, telling Page Six, "He's boldly going where other people have gone before," as he mocked the famous Captain Kirk catchphrase. Takei continued his scathing assessment of Shatner’s trip, adding, "He's a guinea pig, 90 years old and it's important to find out what happens. So 90 years old is going to show a great deal more on the wear and tear on the human body, so he'll be a good specimen to study. Although he's not the fittest specimen of 90 years old, so he'll be a specimen that's unfit!"RELATED: Star Trek's William Shatner Dons His Real-Life Space Uniform in New PhotoAfter returning to Earth, Shatner brutally dismissed Takei’s criticism on Twitter, writing, "Don’t hate George. The only time he gets press is when he talks bad about me. He claims 50+ years ago I took away a camera angle that denied him 30 more seconds of prime time TV. I’m giving it back to him now by letting him spew his hatred for the world to see!"

This is the latest chapter in a seemingly never-ending feud between the two former Starfleet crewmates, as the spat dates back to 1994 when Takei slammed Shatner in his autobiography. There, Takei accused Shatner of ignoring him on set and altering the script for Star Trek V: The Final Frontier to prevent his character from taking command of a ship.

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Things continued to get personal over a decade later when Shatner accused Takei of not inviting him to his wedding during a radio interview. "There is such a sickness there," he said on his YouTube channel. "It's so patently obvious that there is a psychosis there. I don't know what his original thing about me was. I have no idea." Takei has since refuted the claim, stating he did indeed invite Shatner, but he failed to turn up.

For any fans upset by the bickering of the former crewmates, 2017 brought a slightly more comforting chapter to the rivalry. Takei stated that the feud is "silliness" and confirmed the two are cordial with each other when they meet, telling Edmonton Journal, "We do conventions and we do cross paths. I’ll say morning Bill, and he’ll say morning George, and that's it."

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Source: Page Six, Twitter