The Martian

The Martian (2015)

18 corrected entries

(7 votes)

Corrected entry: When the Hermes returns to earth for the gravity assist, it is approaching earth while the earth is spinning towards the ship. To catch a gravity assist, the Hermes should have circled the earth on the other side, catching the rotation of the earth away from the ship. This would pull the ship instead of spinning into it.

Correction: The direction of the Earth's rotation doesn't have an effect on a gravity assist. It's the fact the planet is there that matters. Its rotation doesn't change the gravitational pull.

Corrected entry: Matt Damon proposes using his suit air as an "Ironman" rocket to get across the gap. But any competent space person would recognize that in space, the best option is to simply jump. The two ships are motionless relative to each other. A small push, and he would coast towards the ship, in a straight line. Easily grabbed by the ship. Using an uncontrolled propellant was much more dramatic, but completely unwarranted. Earlier, Martinez was jumping around the ship, and showed the ease of aiming from point to point in space. Someone would have suggested jumping. They are in space, with no gravity, and no atmospheric resistance.

Correction: Jumping wouldn't do it. When he first suggested it, his relative velocity was 42 m/s, and the maximum they could handle was 10 m/s, so unless he could generate at least 32 m/s (about 70 miles per hour) in a jump, it wouldn't do any good. I don't know anyone that can jump at 70+ mph, especially in a spacesuit.


Corrected entry: During the montage where Watney is preparing the potatoes, there is a shot outside in his suit where he attaches a cable or hose to the MAV outside the habitat. You can see the large engines of the MAV above Watney's head and the letters "MAV" on the leg of the vehicle, as well as the remains of the wrecked Rover 1 next to it, right where Martinez left it. By this point in the story, the MAV has already departed the Ares III site. This is supposed to be the MDV - the Mars descent vehicle - and Watney refers to the MDV when he discusses where to get the hydrazine - but it is the bottom of the MAV that is shown.

Correction: The MAV is a two stage vehicle. It has a descent stage, used to bring it down to the Martian surface. Atop the descent stage is the ascent stage which would take the crew back into orbit. When launching the ascent stage, the descent stage serves as a launch pad and is left behind. For historical reference you only need to compare to the LEM's from the Apollo moon missions, which also had a descent stage and ascent stage. When Armstrong and Aldrin first descended to the moon, they burned most of the fuel in the descent stage. As such Watney likely scavenged the remaining fuel from both the MDV and the descent stage/launch platform of the MAV.

Corrected entry: When Mark is receiving the messages outside from Pathfinder, he uses a Sharpie or similar to write messages in his notebook. This is impossible, as in Mars' atmosphere and temperature, the ink should be boiled off or frozen.

Correction: In all the scenes where he is actually seen writing (using what looks like a felt tip pen) he is inside a closed earth like environment. In the one scene where he is waiting by the Pathfinder ready to write it's not clear what type of pen he is using (only the back end is visible), it could be a mechanic pencil for all we know. Anyway the point is moot because diverse types of markers and pens able to write in weather conditions worst than Mars' (even vacuum) has existed since the Apollo missions if not before.

Corrected entry: When Mark is communicating with the scientists at any given point while he is on Mars, they can communicate back and forth within seconds. In reality, it would take between 4.3-21 minutes for a message to reach Mark and vice versa.


Correction: They explain in the movie that it takes 30 minutes between communications. Obviously cut out due to not making people wait between every sentence.

Corrected entry: When Mark had got his helmet glass cracked in the front, he had duct taped it but in the later scene he has a perfectly clear and undamaged helmet. He could not have got it from any other place as all the other astronauts had taken theirs on board the Hermes.

Correction: Much like their food rations, NASA would provide them with numerous extra helmets for redundancy purposes. If one of their helmets were damaged and became unusable while on their mission and there were no extras lying around, then they would be SOL.

Phaneron Premium member

Corrected entry: Duct tape does not perform well in extreme freezing temperatures. The glue does not work well and the fabric is not pliable. When Watney is blown from the HAB, it is dark, unpressurized, and he seals cracks in his helmet with duct tape...Martian low temps are about -100C or -145F, but the duct tape is pliable and tacky. Watney also uses duct tape as strength for the HAB plastic seal, and the duct tape remains flexible and stuck to the plastic despite ballooning in and out. (01:03:25 - 01:04:00)

Correction: You are describing the properties of the duct tape you buy at the local hardware store. There is no evidence this is standard duct tape, just that its appearance is similar. The tape NASA sent with the astronauts to Mars may have been specially developed to work in that environment, including overcoming the issues you mentioned. In fact, NASA would be foolish not to send a tape designed to work in the intended environment.


Corrected entry: It is mentioned in the film that Watney's body would be covered by sand in about a year, but after decades the parachute of Pathfinder is still visible on the surface. (00:42:40)

Correction: The parachute is covered by sand.

Corrected entry: When viewed from the front, the circular gravitational ring of the Hermes normally rotates clockwise. However just after retrieving the payload from the Taiyang Shen, it is rotating anti-clockwise. (01:32:15 - 01:33:30)

Correction: The ship is being shown from the opposite angle in this scene.

Corrected entry: Near the end when Matt is awake after launching the MAV, Commander Lewis mistakenly calls Mark Watley "Matt" when telling him the plans.

Correction: I've listened to this with headphones several times and I can't hear Lewis say "Matt" anywhere. She does say "Copy that, MAV", at one point (referring to the Ares4 Mars Ascent Vehicle Watney is in) - I think this must be what you heard.

I heard it too. She is directly addressing him.

Correction: She says "Copy that", not "Matt."

Corrected entry: Matt Damon spends time philosophizing about the cross being the only flammable thing he can use. Yet anyone lighting a stove with an electric spark knows the better way to ignite a gas-oxygen mix is with a readily available electric spark. Presumably, they liked the drama of Damon blowing himself up, rather than pushing an igniter switch.

Correction: Watney uses an electrical spark to ignite the wood, which was used as kindling to keep the fire going until there was a ready and sustainable supply of hydrogen being produced by the reaction.

Corrected entry: In several shots when Mark is grabbing the tether in space outside the Hermes, both of his palms are outstretched. He cut through one so he could use the air to propel himself towards Hermes, but air is not escaping from his hands.

Correction: I checked. The hole is in his left hand and in all shots where no air jet is visible and the left hand does, he has it clenched, which prevent the air to escape as was shown previously when he get ready to leave the capsule. I was unable to find a shot were the cited mistake were visible.

Corrected entry: In all the outside scenes Watney's flexible spacesuit is un-pressurized and wrinkled. The material folds in to his body, not taut from the interior pressure.

Eric Sundberg

Correction: The whole idea behind the Ares EVA suits is that they are not pressurized; rather they are skin tight, allowing flexibility that pressurized suits do not.

Corrected entry: Johannson states that Mark Whatney's MAV was traveling at 741 m/s and his then altitude was 1350 meters. Then Commander Lewis states this is "too low." This must be too low, as at 741 m/s, he would have past 1350 meters in a little less than 2 seconds instead of the stated 12 minutes from launch to end of burn. This 1350 meters perhaps should have been 1350 km final altitude after the MAV finished its burn. (01:56:45)


Correction: They are referring to orbital speed, not the speed he is going up. A faster orbital speed means he will be travelling further from the planet. His orbital speed is too low and as a result his orbit is too close to the planet to meet up with Lewis.

Corrected entry: Near the end while inside the Rover, Watney is leaving a note to future astronauts: "Take good care of this Rover it saved my life," signed Watnay instead of Watney. (02:00:00)

Ron Wolfe

Correction: You're right that it kind of looks like an "a", but that's only because Watney made the loop so round it mostly obscures the bottom tail. If you look closely you can see it is indeed an "e".


Corrected entry: After being rescued on Sol 561, Watney tells his crewmates he hasn't showered for "a year and a half." But the day he leaves the Hab, Sol 461, Watney steps out of what is the shower, naked and toweling off his wet body and hair. So it has only been 100 Sols since he last showered. Even in Earth time that's less than 4 months - nowhere near a year and a half.


Correction: He took baths, but those aren't exactly the same, and regardless I'm pretty sure he meant a proper bath/shower, one that involved soap.

Then why he couldn't grow more potatoes if he had water?

Lack of water is not the reason Watney can't grow more potatoes after the blowout. He can't grow more potatoes because the potatoes and potato plants were all killed by the cold-there is nothing left to grow. Also, if he had lost his entire water supply...what would he drink?


He would not be able to make that amount of water again, the whole machinery got blown out. And he did not have enough fertilizer (aka poop) at that point.

No we saw him take multiple showers. I came to this site specifically for this error. He took showers. Naked with a towel drying off his very wet hair. So for him to say he hadn't taken a shower the whole time he was there, is a straight error.

Correction: He would not be able to make that amount of water again, the whole machinery got blown out. And he did not have enough fertilizer (aka poop) at that point.

Correction: This issue isn't the water. As stated in the NASA conference room on Earth after the HAB blowout, the freezing temperatures killed the bacterial microbes in the soil which would be required for the plants to grow.

I didn't review the movie, but if NASA said that, it's wrong. Many, probably most, soil bacteria would survive freezing, the colder and dryer the conditions the better. Maybe this is a new mistake?

NASA did say they thought all the bacteria had died. (In the book Watney figures out some survived, as you indicate, but they don't go into this in the movie.) However, the bigger issue is that all the potatoes and potato plants were killed when the Hab blew out and everything inside it was instantly depressurized and frozen. So there is nothing left alive for Watney to grow.


The problem was the potatoes. After being frozen they were no longer able to grow a plant. He had plenty of water and could have got more bacteria from his own feces, so it was the potatoes.

The real problem regarding not being able to grow more food is that all the potatoes and potato plants were killed when the Hab blew out. Watney figures out in the book that some bacteria did indeed survive, as you suggest, and he could indeed make more water (and more poop!). But it doesn't matter because now he has nothing to grow.


Corrected entry: After the Hab blows he gets in the rover, which should always be warm from the nuclear device. However it appears very cold and even shows his breath condensing.

Correction: The Rover in this version (not like the book) goes almost complete vacuum, like the surface of Mars, when the doors are opened. This would cause a flash freeze inside the rover as all air that contains the heat will either be pumped into storage, or sucked out the door. The temp drop would be the same as when the Habitat decompressed, freezing everything in seconds.

Corrected entry: While rationing the prepackaged foods, the last thing he counts is 36 sweet and sour Chicken. If you freeze his written list he already wrote down 50 sweet and sour Chicken a few items above it. And since no other food was repeated I'm guessing it was a flub.

Correction: Per the rules of this site, the requirement to use freeze frame invalidates this posting.

Factual error: After Watney patches the blow out of one of the HAB's airlocks with plastic sheeting, tie down straps, and duct tape, he pressurizes the HAB and the plastic sheeting pushes out like an inflated balloon. Assuming the plastic and duct tape would hold this is correct, however the plastic would be much more taut given the pressure difference inside and outside.

Upvote valid corrections to help move entries into the corrections section.

Suggested correction: The plastic would certainly be flexing in and out because of the pressure of the wind gusts during the storm. We saw earlier that the gusts of the storms were strong enough to blow a suited explorer off their feet and push them across the surface. Let's say that the HAB is pressurized as much as it can be without blowing out of the plastic, tape, and bungees sealing the airlock. A storm gust would still be able to push the flexible plastic in momentarily, and it would pop back out after the gust passed.

The movie took liberties with the physics of Mars. The gusts on Mars wouldn't be able to blow over a person or a spaceship, let alone push them across the surface, but they needed it for the plot. But using the same physics they then have wedded themselves to, it could then be strong enough to cause the plastic to flap, even though in real life it wouldn't. This is more of a deliberate mistake than a factual error since the writers certainly knew what they did didn't match reality.

Except they didn't 'wed' themselves to their fictional physics. Towards the end of the film NASA tells Watney that a flimsy plastic covering on his ascent vehicle will not be dislodged on acceleration to Martian escape velocity because the atmosphere is too thin to cause any problems. That's cheating in anyone's books.

More mistakes in The Martian

Mark Watney: I admit it's fatally dangerous, but I'd get to fly around like Iron Man.

More quotes from The Martian

Trivia: The secret project created to use the Hermes to return to Mars to rescue Watney was called Project Elrond, a reference from the Lord of the Rings (also used in the original book of The Martian). Mitch Henderson, played by Sean Bean, was an attendee at the Project Elrond meeting. Sean Bean also played Boromir, who was an attendee at the Council of Elrond in the LOTR movie.


More trivia for The Martian

Question: Why would NASA decide to send a botanist on a mission to Mars? A planet where no plants can grow.

Answer: Part of his job, aside from also being a mechanical engineer, was to use soil taken from Earth to Mars, mix it with Martian soil then grow seeds in it to see how Martian soil is for growing crops. This would be preparing for a longer term mission where growing full crops to feed the crew would be part of the mission.

Answer: Botanists going to mars can study the ground and the dirt so they could make life on mars. Botanists are also helpful due to oxygen in space, he grows plants on the spacecraft for the oxygen that they give off.

More questions & answers from The Martian

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