Corrected entry: The gravity on Mars is about 1/3 of the gravity on Earth. So, the astronauts weight 1/3 as much, but their mass is the same. Yet, they move about and carry things as if they are on Earth. Objects should have been much lighter, and they should have been slower and more deliberate in their movements, for a lower-gravity environment.
Corrected entry: The spacewalk is replete with violations of physical laws: [1] Thruster exhaust would be necessary only to start and stop motion: not to sustain motion. 'Fuel' would be used only to start and stop motion. Thus, once Terry started towards Woody, she would not be in danger of running out of fuel during the trek. She would only need fuel to stop once she reached him. (Of course, she would need more fuel to start & stop the return trek. But even more fundamentally: Woody would not have expended his fuel load during his transit so Terry wouldn't have needed to come rescue him in the first place.) [2] When the grappling hook was launched, the person holding the launching device would be propelled in the opposite direction as the grappling hook's direction. (The larger the mass, the slower the acceleration, but thruster fuel would still be required to counteract the forces derived from the hook's launch.) [3] When the grappling hook stopped due to its line being fully extended, the line's tension would cause the bodies at both its ends (the hook & the gun with the gun's possessor) to snap towards each other. As erroneously depicted, only the hook end recoiled.
Correction: Terry's husband had greater velocity then Terry, so Terry was in need of fuel to move towards him. This is the reason why she didn't had enough fuel, so your mistake is not so correct.
Corrected entry: The spinning habitation module is far too small and is spinning too slowly to produce any sort of force to simulate gravity. e.g. If you assume that the module has a radius of 5m, and is spinning at 0.2 revs/sec, then an astronaut would be subject to an acceleration of 0.2 m/s squared, or 0.02g.
Correction: Good estimations, but incorrect result. "5m radius" and "0.2 rev/sec" are very reasonable estimations. The formula for centrifugal force is "F = V^2 / r", so F = (circumference * 0.2/sec) ^ 2 / 5m = [(2*5m)*pi * 0.2/sec] ^ 2 / 5m = [(2*pi * m/s) ^ 2] / 5m = (4*pi^2/5) m/s^2 ~ 7.9 m/s^2 That's 7.9. Earth gravity is 9.8, so that's pretty close to Earth gravity: *** 0.8g in fact.
Corrected entry: In space there is no sound at all, so we couldn't hear the explosion of the spaceship.
Correction: As is pointed out every single time something like this gets submitted, the use of sound in space is a standard movie convention and is not considered a mistake.
Corrected entry: On Mars, Gary Sinise spills a bag of M&M's (leading him to figure out the DNA puzzle). When the candy is shown on the floor, you can see that it is Skittles.
Correction: It's M&Ms alright. You can even see the 'M' on the sweets on the floor.
Corrected entry: When the Martian hologram shows Earth, the woman says that it is Earth before the continents separated. However, we see that the continents are indeed divided on the hologram.
Correction: No, they're not. Before the continents separated, about half of the Earth was entirely covered by land and the other part was totally flooded, forming one big ocean. That's where you see the alien ship "landing".
Corrected entry: When the engine fuel leaks out after the meteor hits the ship, it comes out perpendicular to the direction of the ship's motion. Well, if you remember Newton's Laws of motion, then you'll know then an object will continue to move at the same velocity unless subject to a force. So how on earth does the fuel end up behind the ship at the engines? It should continue to move away from the ship, because nothing will make it do otherwise.
Correction: It does keep moving in the same direction, it's the ship that rotates to match the best angle to enter in Mars' atmosphere and, as the fuel was moving perpendicularly away from the ship, what happens is perfectly possible.
Corrected entry: When they are watching the hologram in the giant face, the planets go in the wrong direction around the sun.
Correction: The direction the planets are going depends on where you are viewing it from. We see them going one direction because we are always shown them from what we consider the "top". The Martians may have always viewed them from what we would consider the "bottom" making them appear to go in the opposite direction.
Corrected entry: Black gaffer tape can be seen on the orange plastic, presumably covering holes from punctures and tears. Yet if any of these had occurred the greenhouse covering would have exploded, like a balloon.
Correction: If the material is strong enough it would not have exploded, it would have just deflated. Cheadle's character could have repaired the holes and then reinflated the greenhouse.
Corrected entry: When Tim Robbins is helplessly floating into space, his rescue is not as impossible as it is depicted. It ought to be common knowledge let alone known to an astronaut that an object in a vacuum requires only a minimal amount of thrust to travel almost perpetually in the one direction. Fuel would only be an issue with turning around and returning. They'd only need a tiny bit of thrust to catch him.
Correction: While it only requires a minimal amount of thrust to keep going that is not what they need to do. They must ACCELERATE to a rate faster than Robbins velocity, use more fuel to match velocities with Robbins, use TWICE as much fuel to counter Robbins' AND his rescuer's velocity to go back in the other direction, & and since there is a deadline (entering the Mars atmosphere and burning up) they may have to use even higher accelerations to get to Robbins and to get back to the ship to do it in time. It takes even MORE fuel when you start taking into account overcoming the momentum of the two astronauts.
Corrected entry: Jerry O' Connell refers to earthquakes on Mars. On Mars, earthquakes are called marsquakes.
Correction: Well, technically true, but the word "earthquake" would have been more familiar and more natural for him to use than "marsquake."
Corrected entry: Contrary to popular belief, space is NOT cold. The vacuum is a perfect insulator and therefore an object in a vacuum will only lose heat by radiation, which for a drop of liquid or a human head is very slow. Objects which suddenly find themselves in a vacuum do not suddenly get all icy. Real astronauts had to carry lots of extra oxygen in their space-suits to carry away their excess body heat, otherwise that heat would have nowhere to go, and they would bake.
Correction: Heat is the energy created when two bodies do not share the same temperature. The average temperature of the vacuum of space is about 4kelvin, enough to maintain liquid helium. The rate of radiation is based on the temperature difference, not the surfaces. Real astronauts have both heating and cooling in their suits.
Corrected entry: The space ship's super-computer (with touchscreen, voice-control and stuff) doesn't notice the hole in the fuel tank and the loss of fuel. Even my car can notice fuel-reduction when driving.
Correction: The hole is not in a fuel tank, but in a fuel line, which is pressurised only moments before ignition. So there is no pressure loss before pressurisation of those lines.
Corrected entry: Don Cheanile's character has been stranded on Mars for over a year. How come he can't cut his hair or shave, but his teeth look so white and clean?
Correction: Simple, before he left earth they cleaned his teeth and sterilized his mouth from plaque. The food on the spaceship was likewise sterilized so there would be no more building up. In the spaceship and then in the clean manufactured atmosphere on mars there would also be no pollutants to discolour his teeth.
Correction: When we watched the astronauts perish in the beginning of the movie, you can see that the Martian vortex was able to suck in two of the astronauts effortlessly. That shows how light the gravity is on Mars, because they were sucked in fast through midair. Another scene is when Phil pulls out a metal suitcase and shows it to Luke. That suitcase contained very heavy equipment, but due to Mars gravity he was able to hold it without struggling. One more example is when the remaining crew drag the equipment to base camp. They did struggle, but on Earth it was take more than simply three people to drag that kind of equipment.
Michael Paek