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Gravity Movie --- Factual mistakes and goofs (SPOILERS obviously)


TeeGee

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Hi everyone, Gravity has been bothering me a lot since I watched it in theaters last year, in particular some of the factual issues regarding the Kessler syndrome we observed the characters going through.

IF Russia shot down one of their satellites, which is IN ORBIT, why would debris hit the orbiter once every 90 minutes??

I don't understand how that's possible, because everyone knows that orbital period in LEO is once every 90 minutes, that means that the debris must have been stationary over earth (as in, net velocity of ZERO) and the orbiter was flying through it.. was gravity (no pun intended) not acting to pull this debris towards earth?

If the satellite was in a retrograde orbit, wouldn't they run into the debris once every 45 minutes??

AND WHY does that same debris ram into the ISS Or Tiengong at the same 90 minute intervals?

Does anybody have an explanation for this or any other factual errors that we have not been made aware of yet regarding this film?

PS: Please don't reply with the classic "it's a movie" response. If you are going to advertise a film as being realistic, people are allowed to scrutinize its authenticity of that claim till the day they day. Gravity deserves to be picked apart on a factual level because of this claim, no matter how much audiences enjoyed it.

BTW has anyone tried to reach a space station in KSP like the astronauts did in Gravity (via EVA)? Is it even possible?

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The debris is on a different orbital path, so it goes in and out of the path of the orbiter, and due to exentricity, only hits it on one orbital path.

The only "big" mistakes with the movie were that the Hubble, ISS and Tiangong were in similar orbits...also the Shuttle's retired, but that one is excusable.

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The debris is on a different orbital path, so it goes in and out of the path of the orbiter, and due to exentricity, only hits it on one orbital path.

?? Care to elaborate? Do you mean that the inclination of the debris was different and only crossed the orbit at one location?

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The thing that bothered me the most was when they try to grab onto the ISS. Through luck they manage to halt relative velocity and end up barely sticking to a thin wire.

...

Then for some reason Matt Kowalski is being sucked away from the space station by some kind of force. What is this magical force? The space station isn't thrusting and they're still very close to it, so tidal accelerations should be minimal.

Thanks to wrong physics Kowalski has to detach his harness and sacrifice himself.

Edited by maccollo
Fixed all kinds of typos. Must have been drunk when I wrote this =P
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I really don't understand why people constantly feel the need to constantly bash this movie on its physics accuracy. I constantly see people posting stuff like "Plain unwatchable due to inaccuracies" yet proceed to praise The Dark Knight as the pinnacle of movie making. Does it make them feel smart about themselves or something?

Because Gravity is one of the most accurate sci fi movies I've ever seen. The inaccuracies were minor or intentional. Sure the Hubble, the ISS and the planned chinese station are in vastly different orbits IRL. But else there wouldn't be a story. It'd be: Debris hits, characters run out of supplies and die. Not a good movie, even if its more realistic.

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The thing that bothered me the most was when they try to grab onto the Main station. Through luck the something and halt relative velocity and end up barely sticking to a thin wire.

...

Then for some reason Matt Kowalski is being sucked away from the space station by some kind of force. What is this magical force? The space station isn't thrusting and they're still very close to it, so tidal accelerations should be minimal.

Thanks to wrong physics Kowalski has detach his harness and sacrifice himself.

The station was rotating when they were caught up in the parachute. They only showed it for a couple of seconds with a long-shot, so it wasn't that clear, but that's what flung him clear when he let go.

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The station was rotating when they were caught up in the parachute. They only showed it for a couple of seconds with a long-shot, so it wasn't that clear, but that's what flung him clear when he let go.

That makes sense then. I thought it wasn't because there was a wide angle shot with the earth in plain view as a reference point, and it looked as if everything was no significant rotation.

They could have used that shot to show some significant rotation =P

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Because Gravity is one of the most accurate sci fi movies I've ever seen. The inaccuracies were minor or intentional. Sure the Hubble, the ISS and the planned chinese station are in vastly different orbits IRL. But else there wouldn't be a story. It'd be: Debris hits, characters run out of supplies and die. Not a good movie, even if its more realistic.

This. Enjoy Gravity for its relative lack of inaccuracies, don't hate on it because it still has a few.

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The main reason we criticise this film is that it gets the other stuff right.

Why go halfway? Why not create a film that has EVERYTHING, instead of forcing us to suspend our disbelief? A great story teller can satisfy both the learned and the common if the tale is told well.

I'm just frustrated that this movie was half real and half lazy. Why are filmmakers so terrified of creating a story that shows the beauty of our natural world instead of filling it with dumb explosions and stupid action heroes doing impossible things in the name of cool? Talk to the audiences spirit, not their animal instincts. Stop being so primal, and start using your brain. Challenge us, teach us and heaven forbid, inspire us.

Im tired of losing brain cells whenever I go to watch a movie filled with dumb action. Yes, action is exciting, but creating a movie for the sake of action is very very bad story telling.

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The debris is on a different orbital path, so it goes in and out of the path of the orbiter, and due to exentricity, only hits it on one orbital path.

The only "big" mistakes with the movie were that the Hubble, ISS and Tiangong were in similar orbits...also the Shuttle's retired, but that one is excusable.

The movie is set in an alternate future (around 2020) where the shuttle wasn't retired. Note that the mission name was STS-157. Also the Tiangong is the one they are preparing to build by 2020, and the movie shooting began in 2009, when the shuttle was still there.

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Why go halfway? Why not create a film that has EVERYTHING, instead of forcing us to suspend our disbelief? A great story teller can satisfy both the learned and the common if the tale is told well.

I'm just frustrated that this movie was half real and half lazy. Why are filmmakers so terrified of creating a story that shows the beauty of our natural world instead of filling it with dumb explosions and stupid action heroes doing impossible things in the name of cool? Talk to the audiences spirit, not their animal instincts. Stop being so primal, and start using your brain. Challenge us, teach us and heaven forbid, inspire us.

Im tired of losing brain cells whenever I go to watch a movie filled with dumb action. Yes, action is exciting, but creating a movie for the sake of action is very very bad story telling.

Making the movie 100% realistic was the director's goal at first, but he had to sacrifice that to make the plot work, and believE me, the plot is very deep and thoughtful. I excuse Gravity for some errors, but I don't excuse cr*p like Armageddon. Ugh!

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The station was rotating when they were caught up in the parachute. They only showed it for a couple of seconds with a long-shot, so it wasn't that clear, but that's what flung him clear when he let go.

like i said, momentum doesn't add up, the station would need to be rotating at about 3 times the rate it was in the movie to produce that kind of effect if the tether had minimal friction

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Why go halfway? Why not create a film that has EVERYTHING, instead of forcing us to suspend our disbelief? A great story teller can satisfy both the learned and the common if the tale is told well.

I'm just frustrated that this movie was half real and half lazy. Why are filmmakers so terrified of creating a story that shows the beauty of our natural world instead of filling it with dumb explosions and stupid action heroes doing impossible things in the name of cool? Talk to the audiences spirit, not their animal instincts. Stop being so primal, and start using your brain. Challenge us, teach us and heaven forbid, inspire us.

Im tired of losing brain cells whenever I go to watch a movie filled with dumb action. Yes, action is exciting, but creating a movie for the sake of action is very very bad story telling.

So, how would you have written Gravity? You want to tell a story about a woman moving on from her child's death while using the beauty and danger of space to both drive the plot and hold symbolic meaning.

Remember, you have the use ABSOLUTE accuracy here. You can't use anything that isn't up there right now, else it would be just as 'unrealistic' as the wrong orbits in the real Gravity.

Fiction tells about impossible scenarios and alternate histories for a reason; to explore concepts that you otherwise can't explore, or look at issues from a different angle. If your suspension of disbelief breaks on something as simple as different orbital paths I doubt you could enjoy ANY piece of fiction. And the sheer fact that you compare Gravity to dumb explosions to satisfy our primal instincts shows that you payed very little attention to anything but those action scenes. Action scenes are a part of the movie yes, but they're just the backdrop to a very different story about perseverance through hardship.

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Even those action scenes were well done. One that stood out in my mind was when SB was escaping the burning ISS. There is the roaring of the flames, the popping and banging of compressed gas (there is quite a bit of this on the ISS) bursting out of tanks, etc. Just loads of noise. When she closes the hatch, this gets a bit more muted but is still present as a deep background thrumming. Only when the soyuz actually detaches from the station does the sound suddenly drop out 100% except for her breathing. This was something that even BSG sacrificed to some extent for the sake of action and audience interest.

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So, how would you have written Gravity? You want to tell a story about a woman moving on from her child's death while using the beauty and danger of space to both drive the plot and hold symbolic meaning.

Remember, you have the use ABSOLUTE accuracy here. You can't use anything that isn't up there right now, else it would be just as 'unrealistic' as the wrong orbits in the real Gravity.

Fiction tells about impossible scenarios and alternate histories for a reason; to explore concepts that you otherwise can't explore, or look at issues from a different angle. If your suspension of disbelief breaks on something as simple as different orbital paths I doubt you could enjoy ANY piece of fiction. And the sheer fact that you compare Gravity to dumb explosions to satisfy our primal instincts shows that you payed very little attention to anything but those action scenes. Action scenes are a part of the movie yes, but they're just the backdrop to a very different story about perseverance through hardship.

1) Debris hits orbiter once before reentering atmosphere.

2) They were close to ISS to begin with to dock and complete her construction when hit.

3) No tiengong

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1) Debris hits orbiter once before reentering atmosphere.

2) They were close to ISS to begin with to dock and complete her construction when hit.

3) No tiengong

Why would the debris reenter? The initial object had enough orbital energy to remain in orbit, conservation of momentum says the majority of debris stays up as well.

Why would the astronauts be on EVA during docking? They'd all be inside the orbiter and die when the debris hits.

How come the ISS wasn't hit by the debris? Not like debris can aim. And the ISS has to be intact for them to use the Soyuz for reentry, else they'd just be dead which doesn't make very compelling storytelling.

How does the main character end up alone in a hopeless situation to complete her story arc?

What happened to the crew on the ISS?

Plenty of plotholes, even in your very small and undetailed story mockup.

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I really don't understand why people constantly feel the need to constantly bash this movie on its physics accuracy. I constantly see people posting stuff like "Plain unwatchable due to inaccuracies" yet proceed to praise The Dark Knight as the pinnacle of movie making. Does it make them feel smart about themselves or something?

Because Gravity is one of the most accurate sci fi movies I've ever seen. The inaccuracies were minor or intentional. Sure the Hubble, the ISS and the planned chinese station are in vastly different orbits IRL. But else there wouldn't be a story. It'd be: Debris hits, characters run out of supplies and die. Not a good movie, even if its more realistic.

Whenever I talk about why Gravity gets details wrong, I preamble by saying it's a orbital mechanics primer in comparison to even the recent Star Trek movies because the license taken with speeds and relative motion are proportionately much smaller.

In Gravity, the ISS and Hubble are at their closest 200km apart, twice as far as what's stated in the movie, and on completely different inclinations. For these reasons, it takes nearly as much energy to change orbits from one to the other as doing an entirely new launch (if one is only using the space shuttle). Now, juxtapose if you will:

In the climax of Star Trek: Into Darkness, the Enterprise faces off against that black dreadnought ship in medium lunar orbit. They exchange fire; the dreadnought is crippled but Enterprise is damaged as well, and begins listing. Then the Enterprise suddenly plummets towards the Earth, and they're only able to survive by pulling out of the fall literally at an altitude of less than 200 meters. The distance covered by the Enterprise in this "listing" due to being shot, is going from medium lunar orbit, to nearly sea level on earth, in less than 20 minutes of real time. This means that by being shot by the Dreadnought, the Enterprise accelerated to about 250 km/s (0.008c, or 8.63 million kilometers per hour) seamlessly, without being noticed and completely by accident.

In Star Wars, it is not unusual for vessels the size of small islands to be able to accelerate in excess of 2000 g-forces- a force which is compensated for by devices usually not much larger than a small fraction of the vessel's full size or energy demand, which is so robust it never actually causes a problem as seen in any of the movies.

In Gravity, for the sake of the audience's viewing pleasure space debris is slowed down to a speed necessary to make it possible to see (because usual free and random intercept speed of debris is many times the speed of a bullet, making it too fast to be seen).

In almost every movie with them, lasers travel at speeds slightly less than the speed of sound, to make visible light beams and darts of "pure energy" fling around like dramatic space arrows.

Gravity earns its merit through the details that weren't thrown away for the sake of drama. Don't crucify it because Hollywood thinks the general public is so stupid: crucify Hollywood.

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I really don't understand why people constantly feel the need to constantly bash this movie on its physics accuracy. I constantly see people posting stuff like "Plain unwatchable due to inaccuracies" yet proceed to praise The Dark Knight as the pinnacle of movie making. Does it make them feel smart about themselves or something?

At no point wast the Dark Knight pretending in any way to be realistic. Gravity was pretending to be. That's the big difference you're missing.

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At no point wast the Dark Knight pretending in any way to be realistic. Gravity was pretending to be. That's the big difference you're missing.

How was it pretending to be completly realistic? Was there a big sign that said 100% REALISTIC MOVIE that I didn't see? If you want to be picky 2001 A Space Oddesy is unrealistic because they are walking as if affected by Earth like gravity on The Moon. the majority of the scientific mistakes were intentional to help advance the plot.

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Why would the debris reenter? The initial object had enough orbital energy to remain in orbit, conservation of momentum says the majority of debris stays up as well.

Why would the astronauts be on EVA during docking? They'd all be inside the orbiter and die when the debris hits.

How come the ISS wasn't hit by the debris? Not like debris can aim. And the ISS has to be intact for them to use the Soyuz for reentry, else they'd just be dead which doesn't make very compelling storytelling.

How does the main character end up alone in a hopeless situation to complete her story arc?

What happened to the crew on the ISS?

Plenty of plotholes, even in your very small and undetailed story mockup.

1) Debris hits once, at the beginning of the movie

2) Debris hits everything on that inclination orbit, including the ISS

3) Orbiter is near ISS and the crew is retrieving a detached module that fell off of the ISS due to neglect or damage from previous debris strikes

4) Kessler syndrome is an already established problem in the film.

There, fixed it.

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1) Debris hits once, at the beginning of the movie

2) Debris hits everything on that inclination orbit, including the ISS

3) Orbiter is near ISS and the crew is retrieving a detached module that fell off of the ISS due to neglect or damage from previous debris strikes

4) Kessler syndrome is an already established problem in the film.

There, fixed it.

1) If the debris were travelling fast enough to impact the space craft they would already have orbital velocity.

2) Ok so the debris hit the ISS as well. Rendering it destroyed.

3) Further supports the point that ISS is destroyed, meaning crew are still dead and a boring movie.

4) Ok, so debris hit ISS, module falls off the ISS due to debris strike rendering ISS effectively destroyed.

You fixed a couple of holes, and dug a fair few more.

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1) Debris hits once, at the beginning of the movie

Sure, but you can understand why they had it come back several times, right? It maintains dramatic tension. By getting rid of the main "villain" right at the start you're going to have to work that much harder to make a compelling movie.

Edited by Seret
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