Plot hole: Further to the comments about the Lunar Lander being useless as a Mars Lander - who is going to believe that three men spent eighteen months crammed into a tiny Lunar Command Module? Not only would they go out of their minds, where would they store the tonnes of water and food they would need in that tiny capsule? How could the Service Module carry enough oxygen or have enough battery power to make the trip?
Plot hole: The "death" of the three astronauts and the requirement to then fake the whole scenario of the failed mission was obviously unplanned - it came about because of an unexpected computer glitch which reported that they had burned up on reentry, causing a mad scramble to cover up the fake mission and kill the astronauts. Obviously it was planned to have the astronauts "return" to Earth as heroes after their supposed trip to Mars, maintaining their deception (under threat if necessary) for the rest of their lives. One problem. Every scientist on earth would be champing at the bit to get their hands on a sample of Martian rock. Samples would be worth billions, worth far more than Moon rocks are worth today. How was NASA going to explain they didn't have any? They could not possibly fake the rocks - Martian soil and rocks would have a number of identifiable characteristics that a smart first year college student could identify. Using Martian meteorites collected from the Earth's surface won't work, either - prolonged exposure to the Earth's atmosphere would leave tell tale weathering and chemical changes that would be instantly detectable. NASA have painted themselves into a corner and that is not something they would have failed to realise well in advance.
Suggested correction: They could use meteors that had landed on Earth. This is one of the theories for the "faked" moon landing, that they either created the moon rocks from scratch, or collected meteors. As for the death of the astronauts, that's not a plot hole, it's the plot of the movie; the powers that be wanted the men to fake everything and return as heroes. When they wouldn't play along, it was decided they needed to be eliminated.
It is clear from the narrative of the film that it was planned that the astronauts would "land" safely. Using meteorites would not work - exposure to the Earth's atmosphere would mean (and has meant) that the rocks would show weathering and chemical changes that anyone would be able to detect.
Continuity mistake: Astronauts are escaping in desert. The one who survives cuts off piece of material from bottom of his left pant leg. He ties material around his head like a headband. Later he is standing and it looks like left pant leg is uncut, and he's wearing the headband.
Suggested correction: If you look, you can see he pulled his pant leg up (you can see the zipper). What he cut was his undergarment, not his pants. You can even see where his undergarment is torn from the tearing.
Continuity mistake: Brubaker has a beard in the cave, but not at the gas station.
Suggested correction: He doesn't have a beard in the cave, he has dirt and dust on his face.
Suggested correction: You're assuming they travelled from Earth to Mars in the lander alone. The astronauts didn't do this when they went to the moon. The Lunar Lander was attached to the command module during the 3-day journey. When the astronauts reached the moon, they detached the lander from the command module and landed on the surface. It is reasonable to believe the astronauts for Capricorn One did the same thing, except on a much bigger ship for a journey that lasted over a year. We just never saw it.
Mike Lynch
The posting did not refer to the Lunar Lander, it referred to the tiny Lunar Command Module, the only part of the Saturn V that returned to Earth. From 44:00 to 48:08 of the film we see a live broadcast, supposedly from Martian orbit, showing all three astronauts crammed into a Lunar Command Module. The posting is absolutely correct.
This is another Deus ex Machina explanation for a blatant film mistake. The astronauts launched into orbit in a standard Saturn V rocket which could not possibly carry anything like a spacecraft large enough to make the trip to Mars. There is nothing in the film to suggest that there was a "much bigger ship" involved.
They are also shown seated in the tiny Apollo command module, supposedly transmitting messages from orbit around Mars. The posting is absolutely correct.
You're assuming the astronauts were launched in a standard Saturn V rocket, but with all the resources needed for a journey to Mars that took 18 months round trip, NASA would have to send them on a larger rocket to accommodate the required oxygen, water, food, spare parts, supplies, etc. needed to bring them back safely.
Mike Lynch
Did you watch the film? From 1:54 to 2:25 we see an establishing shot of a perfectly ordinary Saturn V rocket on the launch pad. From 6:05 to 6:43 we see all three astronauts strapped into the tiny, Lunar Command Module. As has already been pointed out from 44:00 to 48:08 we see a live broadcast, supposedly from Martian orbit, showing all three astronauts crammed into a Lunar Command Module. There is absolutely no mention of a larger spacecraft and none is ever shown.