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Factual error: Amongst the essential parts of a nuclear weapon's detonation mechanism is a radioactive isotope of tritium, which has a half life of just 12 1/2 years. The tritium in every nuke on earth has to be replaced every ten years or so. This is by no means unusual; there are other perishable parts including detonators made of conventional explosives which would be completely inert after a thousand years. After lying dormant with no maintenance at all for that amount of time the nuclear weapons the 'Man-animals' find would be big shiny paperweights and not much else.
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Factual error: The serum is transported by blood. Hair has no blood traveling to it, only the root. So, unless Bacon shaved his body clean, his hair wouldn't have become invisible, likewise all of the fur on the gorilla.
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Factual error: Gary Sinise looks at a computer screen with a short section (about two full twists) of DNA on it and proclaims that "This DNA looks human." He could have been looking at DNA from any single-celled organism and it would have looked just as human as what he was looking at. All mammals have 90+ percent of their DNA in common, he would have to have sequenced the entire DNA strand (something like 3 billion pairs of nucleotides) to identify it as human, something that would be totally beyond the capacity of anything but a well-equipped genetics lab, something they show no sign of having.
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Factual error: A ham radio requires the person to hold down the button while talking. Numerous times in the movie they are talking without pushing the button.
Suggested correction: This is actually subtly addressed in the film. The magic which allows the radio to work across time also allows the two men to speak without pressing the button. There is a moment where Frank wonders what is going on with the radio and presses the button a few times to talk but then notices that he doesn't have to press the button to be heard.
If that was true, then it wouldn't make sense for them to continue to show Frank and John hitting the squawk bar throughout the film.
That is a separate issue. The mistake entry states that you need to hold the button to talk on a ham radio, which is true, but the magic ham radio in the film doesn't require it. If the actors continue to occasionally press the button that could be considered a character mistake but it could also simply be a force of habit by the characters.
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Factual error: The helicopter markings and paint schemes are exclusive ONLY to POTUS (President of the United States). Senator Kelly, even thought he's trying to get a Presidential bid, wouldn't be allowed to fly around in aircraft marked like that. (00:30:10)
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Factual error: When Arnold is in the police station reporting that he has a clone and passes through a control room, one computer screen is flashing "OVERIDE." The correct spelling is "OVERRIDE." (00:38:05)
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Factual error: The shuttle re-entry being nose-down could never happen. You had to hit the atmosphere nose-up so the ceramic tiles took the heat.
Suggested correction: Not totally true, the nose and leading edge wing were RCC and could take 2300°F, just like the tiles on the underside.
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Factual error: The roach-like insects that are apparently eating the algae and "producing oxygen" are continually referred to as nematodes. Nematodes are actually tiny round worms that have unsegmented bodies (unlike an earthworm).
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Factual error: KCN does not causes you to internally bleed, so Yuka Nakagawa wouldn't have spat up blood and died like that in the lighthouse, but would have rather died due to cessation of respiration.
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Factual error: When the group is travelling through the canyon near the end of the film, they are burning liquor to light the way, yet there is a lot more light than would be given off from this small flame. And none of it is flickering as would happen with a naked flame.
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Factual error: Capt. Towers (4 rings on his shoulder) would be addressed as Captain, not Commander. And when he was promoted to Admiral he never displayed that rank.
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Factual error: The ship goes to rescue someone 3000 light years away. But the shockwave from the 9th dimensional matter explosion is estimated to reach earth in 51 years. It would travel at light speed or less.
Suggested correction: The serum could have been absorbed by the roots and made its way to the tip of the hair strands (similar to colored water going up a piece of celery, changing the color of the celery).
Mammal hair is not porous and is not subject to capillary action.