Gravitar

Rot your brains, then rot our boards

Moderators: SecondTalon, Moderators General, Prelates

User avatar
Mother Superior
Better than tea
Posts: 2405
Joined: Tue Feb 27, 2007 9:30 am UTC
Location: Sweden
Contact:

Gravitar

Postby Mother Superior » Sun May 12, 2013 4:58 pm UTC

Saw this (Hi btw, haven't been here for a while :) ) and thought this'd be a fitting place to share it, since I didn't find a thread for it.

So yeah, this looks... awesome! But they should definitely have three versions running at the cinema; one in 3D, one in 2D, and one in 2D but without sound effects.
My crappy creepy? Crabby? My crabby blog.
"She bore also the fruitless deep with his raging swell, Pontus, without sweet union of love."
- Hesiod, Theogony

User avatar
Izawwlgood
WINNING
Posts: 18686
Joined: Mon Nov 19, 2007 3:55 pm UTC
Location: There may be lovelier lovelies...

Re: Gravity

Postby Izawwlgood » Sun May 12, 2013 5:12 pm UTC

So, Open Water, but in space?
... with gigantic melancholies and gigantic mirth, to tread the jeweled thrones of the Earth under his sandalled feet.

User avatar
SlyReaper
inflatable
Posts: 8015
Joined: Mon Dec 31, 2007 11:09 pm UTC
Location: Bristol, Old Blighty

Re: Gravity

Postby SlyReaper » Sun May 12, 2013 6:51 pm UTC

Looks nice, but I get the horrible feeling that if I actually go and watch this, I'm going to be sitting there quietly seething the whole time because they'll get the details wrong. I can already see from the trailer that the spaceship somehow disintegrates and then the debris seems to be re-entering. Nope nope nope, that would not happen. ORBITS DO NOT WORK THAT WAY. GOODNIGHT.

Of course I may be entirely wrong, and there's actually some realistic mechanism to cause that to happen, but... it's Hollywood. So nope.

For the parts of the film that are actually likely to be decent, look here. Except that's not CGI, that's time-lapse video.
Image
What would Baron Harkonnen do?

User avatar
charliepanayi
Posts: 1531
Joined: Sat Sep 27, 2008 7:26 pm UTC
Location: London, UK

Re: Gravity

Postby charliepanayi » Sun May 12, 2013 7:10 pm UTC

It's Alfonso Cuaron, so I'm optimistic. The guy's made some fine films.
"Excuse me Miss, do you like pineapple?"

"I don't want to achieve immortality through my work, I want to achieve it through not dying"

User avatar
Diadem
Posts: 5654
Joined: Wed Jun 11, 2008 11:03 am UTC
Location: The Netherlands

Re: Gravity

Postby Diadem » Sun May 12, 2013 10:06 pm UTC

SlyReaper wrote:Looks nice, but I get the horrible feeling that if I actually go and watch this, I'm going to be sitting there quietly seething the whole time because they'll get the details wrong. I can already see from the trailer that the spaceship somehow disintegrates and then the debris seems to be re-entering. Nope nope nope, that would not happen. ORBITS DO NOT WORK THAT WAY. GOODNIGHT.

Of course I may be entirely wrong, and there's actually some realistic mechanism to cause that to happen, but... it's Hollywood. So nope.

Actually, that's not wrong. An explosion would cause debris to scatter in all directions. Of course none of it will have a lot of velocity compared to the speed with which it is already flying around the earth, so most will just end up in a slightly different orbit, but some will definitely end up burning up in the atmosphere. The energy required to go from LEO to 'crashing to earth' is not so big that some of the debris won't make it.

If they have the station exploding and all of it burning up, or some of it burning up immediately after, then that's bogus. But it did not seem to be all of it, and the timing is hard to tell from a trailer.
It's one of those irregular verbs, isn't it? I have an independent mind, you are an eccentric, he is round the twist
- Bernard Woolley in Yes, Prime Minister

OP Tipping
Posts: 262
Joined: Thu Dec 13, 2007 6:23 am UTC

Re: Gravity

Postby OP Tipping » Sun May 12, 2013 10:14 pm UTC

I'm very curious about how they are going to get out of it.
a) Please explain the specific MEDICAL reason for ordering this MEDICATION !
b) Please state the nature of your ailment or injury.
c) One a scale of one to ten, how would you rate your pain?
d) Please state the nature of the medical emergency.

User avatar
SlyReaper
inflatable
Posts: 8015
Joined: Mon Dec 31, 2007 11:09 pm UTC
Location: Bristol, Old Blighty

Re: Gravity

Postby SlyReaper » Mon May 13, 2013 7:23 am UTC

Diadem wrote:Actually, that's not wrong. An explosion would cause debris to scatter in all directions. Of course none of it will have a lot of velocity compared to the speed with which it is already flying around the earth, so most will just end up in a slightly different orbit, but some will definitely end up burning up in the atmosphere. The energy required to go from LEO to 'crashing to earth' is not so big that some of the debris won't make it.

If they have the station exploding and all of it burning up, or some of it burning up immediately after, then that's bogus. But it did not seem to be all of it, and the timing is hard to tell from a trailer.

It would cause some debris to re-enter yes, but that looked like the whole thing. Certainly a large enough portion that it would have required a huge shove in the coincidentally right direction to make it fall from the sky, and that didn't look like a huge shove, so much as a slow disintegration. Unless I'm mistaken, you still need a good few hundred meters per second delta-v to return from the space station.

Another wrong detail - the text said they're 350 miles up. The ISS is only about 250 miles up. Or is this some different station that happens to look identical?
Image
What would Baron Harkonnen do?

OP Tipping
Posts: 262
Joined: Thu Dec 13, 2007 6:23 am UTC

Re: Gravity

Postby OP Tipping » Mon May 13, 2013 9:36 am UTC

The other thing is that the shuttle is out of commission...

Is it supposed to be set in an alternative past, or do they come up with some reason to unmothball the shuttle?
a) Please explain the specific MEDICAL reason for ordering this MEDICATION !
b) Please state the nature of your ailment or injury.
c) One a scale of one to ten, how would you rate your pain?
d) Please state the nature of the medical emergency.

User avatar
Adam H
Posts: 1267
Joined: Thu Jun 16, 2011 6:36 pm UTC

Re: Gravity

Postby Adam H » Thu Sep 12, 2013 2:23 pm UTC

So this movie is apparently really good according to like every critic who has seen it. James Cameron has said it's the best space film ever done? Better than 2001 Space Odyssey (and The Empire Strikes Back, if that's a "space film") I guess?

But to be honest, Sandra Bullock is what really makes me want to see this movie.

Mother Superior wrote:So yeah, this looks... awesome! But they should definitely have three versions running at the cinema; one in 3D, one in 2D, and one in 2D but without sound effects.
Sound effects: "Cuarón has confirmed that scenes in space will be silent: 'They put in explosions [in the trailer]. As we know, there is no sound in space. In the film, we don't do that.'"
-Adam

User avatar
Izawwlgood
WINNING
Posts: 18686
Joined: Mon Nov 19, 2007 3:55 pm UTC
Location: There may be lovelier lovelies...

Re: Gravity

Postby Izawwlgood » Thu Sep 12, 2013 3:17 pm UTC

Adam H wrote:But to be honest, Sandra Bullock is what really makes me want to see this movie.
You know, it's funny, but despite not really thinking she's been in many phenomenal roles, I really like her as an actress.

Diadem wrote:An explosion would cause debris to scatter in all directions.
Out of curiosity, if you provide a really large 'towards Earth' force, wouldn't that render the orbit of those portions of debris elliptical? Potentially elliptical enough to skip into atmo? Or is the delta-v required to do so high enough that you'd end up vaporizing whatever collided?
... with gigantic melancholies and gigantic mirth, to tread the jeweled thrones of the Earth under his sandalled feet.

nitePhyyre
Posts: 1280
Joined: Mon Jul 27, 2009 10:31 am UTC

Re: Gravity

Postby nitePhyyre » Thu Sep 12, 2013 6:23 pm UTC

Izawwlgood wrote:Out of curiosity, if you provide a really large 'towards Earth' force, wouldn't that render the orbit of those portions of debris elliptical? Potentially elliptical enough to skip into atmo? Or is the delta-v required to do so high enough that you'd end up vaporizing whatever collided?
It depends. Lot's of variables here. The shuttle & ISS are in LEO and haven't completely left atmosphere. they are in decaying orbits, and need to keep adding thrust to keep from crashing into earth. I don't think that a push towards earth would have enough energy to make it back out the other side. If it did, it would be in a decaying orbit, definitely wouldn't be in a stable elliptical orbit. Also, when you say 'towards earth' do you mean 'down' or 'retrograde'. If down, depending on the perpendicularity of the thrust and its size, you might be able to slingshot out of orbit.

Damn it, now I want to play KSP and I'm at work. Thanks a lot.
sourmìlk wrote:Monopolies are not when a single company controls the market for a single product.

You don't become great by trying to be great. You become great by wanting to do something, and then doing it so hard you become great in the process.

User avatar
Izawwlgood
WINNING
Posts: 18686
Joined: Mon Nov 19, 2007 3:55 pm UTC
Location: There may be lovelier lovelies...

Re: Gravity

Postby Izawwlgood » Thu Sep 12, 2013 6:42 pm UTC

nitePhyyre wrote:Also, when you say 'towards earth' do you mean 'down' or 'retrograde'.
Yeah that wasn't clear; I meant 'down', as in, perpendicular to the direction of movement. Retrograde would be like a head on collision.
nitePhyyre wrote:If down, depending on the perpendicularity of the thrust and its size, you might be able to slingshot out of orbit.
I wouldn't imagine that debris would be capable of dipping into atmo without burning up?
... with gigantic melancholies and gigantic mirth, to tread the jeweled thrones of the Earth under his sandalled feet.

nitePhyyre
Posts: 1280
Joined: Mon Jul 27, 2009 10:31 am UTC

Re: Gravity

Postby nitePhyyre » Fri Sep 13, 2013 6:14 pm UTC

Izawwlgood wrote:
nitePhyyre wrote:If down, depending on the perpendicularity of the thrust and its size, you might be able to slingshot out of orbit.
I wouldn't imagine that debris would be capable of dipping into atmo without burning up?
Yeah, kinda forgot we were talking about debris, was just thinking of the shape of the orbits. Maybe if the debris particle happened to be an aerodynamic shape and made out of temperature resistant material, but it is unlikely.
sourmìlk wrote:Monopolies are not when a single company controls the market for a single product.

You don't become great by trying to be great. You become great by wanting to do something, and then doing it so hard you become great in the process.

User avatar
Pez Dispens3r
is not a stick figure.
Posts: 2079
Joined: Thu Dec 04, 2008 3:08 am UTC
Location: Australia
Contact:

Re: Gravity

Postby Pez Dispens3r » Wed Oct 02, 2013 9:39 am UTC

SlyReaper wrote:Another wrong detail - the text said they're 350 miles up. The ISS is only about 250 miles up. Or is this some different station that happens to look identical?


They're actually referring to Hubble, there.

SlyReaper wrote:I can already see from the trailer that the spaceship somehow disintegrates and then the debris seems to be re-entering.


Yeah, the trailer seems to show that, but it seems more plausible once you see the actual film. I think they did a rather good job with everything, in fact. But I did notice these problems (spoilers):

Spoiler:
Only because I heard about it recently, but Ryan (Sandra Bullock) cries in space and her tears come away in droplets when they should stick to her eyes and not really go anywhere.

I thought communications and GPS satellites weren't in LOE so it seemed weird that they lose both at the start of the film.
Mighty Jalapeno wrote:I feel like you're probably an ocelot, and I feel like I want to eat you. Feeling is fun!
this isn't my cow

User avatar
Diadem
Posts: 5654
Joined: Wed Jun 11, 2008 11:03 am UTC
Location: The Netherlands

Re: Gravity

Postby Diadem » Fri Oct 04, 2013 8:15 pm UTC

Went to see this movie today.

I really liked it. In fact it's probably the best movie I've seen this year (and I have an unlimited cinema subscription, so I watch nearly everything). Especially the scene near the start, just after the shit hits the fan is really impressive. High Octane Nightmare Fuel of the purest sort.

Of course the physicist in me regularly cried at all the mistakes. But they got the 'no sound in space' thing right, and also Newton's laws, mostly, which is already a lot more than most movies. The middle of the movie was a bit sappy at times, especially the "I won't let you go" scene. But the start and ending were very good. I also really liked the pacing of this movie. It's rare to see an action movie where they do not rush things.

spoilers below.
Spoiler:
The first scene I was referring is the one where Sandra was spinning around alone in space. Damn scary, and extremely well done. Of course most of the film was a bit ridiculous. The fact that she got rescued in the first place already stretches believability, but everything else after was even more unrealistic. The scene were Matt Kowalski died was ridiculously sappy, and also unrealistic. They should have bounced back to the station by the mere fact of the line being pulled tout, not to mention that a very light tuck would have sufficed to pull him back in.

While they got the most important physics parts right, they got almost every single detail wrong. The fire scene was stupid, the reentry scene made no sense, the walking from station to station made no sense, the fact that the debris returned every 90 minutes made no sense. Even minor details were wreong. They were floating over Egypt (which was a beautiful shot) with the sun just rising in the east, and they mentioned it was 8 o'clock in central USA, which doesn't compute. Also, the sun should be sinking, not rising, because they were floating westwards, and in leo you move significantly faster than the sun. I could go on for a while, they made a ridiculous amount of mistakes. But the movie was overall still very good.
It's one of those irregular verbs, isn't it? I have an independent mind, you are an eccentric, he is round the twist
- Bernard Woolley in Yes, Prime Minister

User avatar
Zohar
COMMANDER PORN
Posts: 8565
Joined: Fri Apr 27, 2007 8:45 pm UTC
Location: Denver

Re: Gravity

Postby Zohar » Fri Oct 04, 2013 9:07 pm UTC

I'm really worried this movie will feel super stressful and anxiety-inducing to me.
Mighty Jalapeno: "See, Zohar agrees, and he's nice to people."
SecondTalon: "Still better looking than Jesus."

Not how I say my name

User avatar
Pez Dispens3r
is not a stick figure.
Posts: 2079
Joined: Thu Dec 04, 2008 3:08 am UTC
Location: Australia
Contact:

Re: Gravity

Postby Pez Dispens3r » Mon Oct 07, 2013 7:39 am UTC

It might be, Zohar, unfortunately. But you're in good hands with the director and he does give you moments to pause and breathe. After the initial assault, when he fully indulges in the panic of drifting off into space, it's a bit more standard action-adventurey.
Mighty Jalapeno wrote:I feel like you're probably an ocelot, and I feel like I want to eat you. Feeling is fun!
this isn't my cow

AngelaL
Posts: 4
Joined: Wed Oct 09, 2013 10:10 am UTC

Re: Gravity

Postby AngelaL » Fri Oct 11, 2013 12:36 pm UTC

SlyReaper wrote:ORBITS DO NOT WORK THAT WAY. GOODNIGHT.

Yep, there are lots of details that are failed, but the message of the movie is really awesome and the visual effects are totally worth watching

User avatar
Izawwlgood
WINNING
Posts: 18686
Joined: Mon Nov 19, 2007 3:55 pm UTC
Location: There may be lovelier lovelies...

Re: Gravity

Postby Izawwlgood » Fri Oct 11, 2013 2:24 pm UTC

I haven't seen it, but a friend of mine had the primary issue of it sort of scare mongering space. We presently have a seriously lack of interest in space; we don't need a movie doing what Jaws did to summer beach tourism for the public approval.

That said, I haven't seen it.
... with gigantic melancholies and gigantic mirth, to tread the jeweled thrones of the Earth under his sandalled feet.

User avatar
Adam H
Posts: 1267
Joined: Thu Jun 16, 2011 6:36 pm UTC

Re: Gravity

Postby Adam H » Fri Oct 11, 2013 2:40 pm UTC

Izawwlgood wrote:I haven't seen it, but a friend of mine had the primary issue of it sort of scare mongering space. We presently have a seriously lack of interest in space; we don't need a movie doing what Jaws did to summer beach tourism for the public approval.
Nah, the better analogy would be to look at what Jaws did to the field of oceanography. I don't believe that the movie discouraged professional ocean exploring. Just amateur ocean dipping-the-toes-in.

Now if space tourism was a popular thing then this movie would probably be a problem. :)
-Adam

nitePhyyre
Posts: 1280
Joined: Mon Jul 27, 2009 10:31 am UTC

Re: Gravity

Postby nitePhyyre » Fri Oct 11, 2013 4:36 pm UTC

Izawwlgood wrote:I haven't seen it, but a friend of mine had the primary issue of it sort of scare mongering space. We presently have a seriously lack of interest in space; we don't need a movie doing what Jaws did to summer beach tourism for the public approval.
No more so than a movie with a car chase being scare mongering of highways.

Jaws was a horror movie, Gravity is an action/adventure.
sourmìlk wrote:Monopolies are not when a single company controls the market for a single product.

You don't become great by trying to be great. You become great by wanting to do something, and then doing it so hard you become great in the process.

infernovia
Posts: 931
Joined: Thu Jul 17, 2008 4:27 am UTC

Re: Gravity

Postby infernovia » Sat Oct 12, 2013 4:14 pm UTC

This movie is just a bit short of phenomenal. It's not scientifically proper, but the movie has succeeded in so many fronts that anyone who is worried about that trivial detail is missing the point.

a) CGI is amazing. You can hardly tell the difference, and the movie is mostly CGI. The earth looks spectacular, the scenes look amazing, the whole movie looks so real that I wondered how they could have made it.
b) Camera/Cinematography. Fantastic. Long scene with no cuts, smoothly transitions the camera between first person and over the shoulder third person and third person with camera close to the main actors. This means you are very very drawn into the perspective of the main character and there is very little barrier "separating" you from the action. Highly immersive, intense, and a triumph in movie making. It fixes every single issue I had with Iron Man 3 cinematography, which I considered abysmal.
c) Good physics, I mean it's not perfect and there are stuff that don't make sense, BUT HOLY SHIT, IT'S 0G.
d) Great pacing. It's a great thriller.

User avatar
gmalivuk
GNU Terry Pratchett
Posts: 26818
Joined: Wed Feb 28, 2007 6:02 pm UTC
Location: Here and There
Contact:

Re: Gravity

Postby gmalivuk » Mon Oct 14, 2013 2:06 am UTC

I don't think it's what's actually portrayed in the movie (I haven't seen it yet), but there are orbits that intersect exactly once each period with enough relative velocity to be dangerous.
Unless stated otherwise, I do not care whether a statement, by itself, constitutes a persuasive political argument. I care whether it's true.
---
If this post has math that doesn't work for you, use TeX the World for Firefox or Chrome

(he/him/his)

rhetorical
Posts: 103
Joined: Wed Apr 21, 2010 12:44 am UTC

Re: Gravity

Postby rhetorical » Thu Oct 17, 2013 6:09 pm UTC

gmalivuk wrote:I don't think it's what's actually portrayed in the movie (I haven't seen it yet), but there are orbits that intersect exactly once each period with enough relative velocity to be dangerous.


Pretty sure it's not. The debris appears to either be travelling in the same orbit as the ISS, but twice as fast, or it is "floating" in a geostationary position at the same height as the ISS (can't remember which direction the debris comes from in the movie). Either way, impossible.

ETA: I guess one way this could work is if the debris is in a polar orbit with the same orbital radius as the ISS's equatorial orbit. Don't think that's what we see in the film, though.

User avatar
gmalivuk
GNU Terry Pratchett
Posts: 26818
Joined: Wed Feb 28, 2007 6:02 pm UTC
Location: Here and There
Contact:

Re: Gravity

Postby gmalivuk » Thu Oct 17, 2013 6:15 pm UTC

Polar orbit wouldn't work, anyway, because it'd intersect at the other side as well. For orbiting bodies to meet exactly once per period they'd need to be in orbits with different eccentricity. And in that case, the other body would be coming from above or below at the point of collision, not in the same orbital path.

I imagine in the movie it was treated as a land or water vehicle, which pretty much stops moving when it turns into a bunch of debris.
Unless stated otherwise, I do not care whether a statement, by itself, constitutes a persuasive political argument. I care whether it's true.
---
If this post has math that doesn't work for you, use TeX the World for Firefox or Chrome

(he/him/his)

User avatar
Pez Dispens3r
is not a stick figure.
Posts: 2079
Joined: Thu Dec 04, 2008 3:08 am UTC
Location: Australia
Contact:

Re: Gravity

Postby Pez Dispens3r » Mon Oct 28, 2013 1:12 pm UTC

Izawwlgood wrote:I haven't seen it, but a friend of mine had the primary issue of it sort of scare mongering space. We presently have a seriously lack of interest in space; we don't need a movie doing what Jaws did to summer beach tourism for the public approval.

That said, I haven't seen it.

Kinda seconding what everyone else is saying, but I don't think that's a legitimate concern. Firstly, this film makes space look absolutely fucking gorgeous. Terrifying, yes, because canned monkeys are never really that safe, but at the same time it makes the space programme seem worth it just for the beauty of it all. I've been recommending this film without reservation to all my space-geek friends for exactly this reason. I'm a huge sci-fi nerd, I have a decent imagination, and I've never felt closer to what it is to be an astronaut than with this film.

Secondly (mild spoiler):

Spoiler:
This is a very optimistic film. The final scene is triumphant, and in the context of that last scene it makes sense why this film which is not about gravity is called Gravity, because it signals that although humanity is utterly grounded for the next century or so we are still determined to head into space. Contrast that to fucking 2001 which is like: every time we evolve, we just get destructive with our new tools (exactly what is that space baby going to eat once it is birthed?)


gmalivuk wrote:I imagine in the movie it was treated as a land or water vehicle, which pretty much stops moving when it turns into a bunch of debris.


The film takes liberties with the whole catastrophic space debris scenario, but it's better than that. I think it's a relative velocity deal, just one that is heavily dramatised and maybe couldn't actually happen. (I suspect you'll agree with me if you see it. This is a film you have to see, and I rather suspect you'll enjoy it more than you mean to if you do).
Mighty Jalapeno wrote:I feel like you're probably an ocelot, and I feel like I want to eat you. Feeling is fun!
this isn't my cow

User avatar
Ryom
Posts: 686
Joined: Fri Aug 24, 2007 7:52 am UTC

Re: Gravity

Postby Ryom » Wed Oct 30, 2013 12:02 am UTC

I'm thinking of renaming this movie "Slow pans up Sandra Bullock's body... in spaaaaace"

infernovia
Posts: 931
Joined: Thu Jul 17, 2008 4:27 am UTC

Re: Gravity

Postby infernovia » Fri Nov 01, 2013 2:23 am UTC

Neil deGrasse Tyson wrote:To "earn" the right to be criticized on a scientific level is a high compliment indeed. So when I saw a headline proclaim, based on my dozen or so tweets, "Astrophysicist says the film Gravity is Riddled with Errors", I came to regret not first tweeting the hundred things the movie got right: 1) the 90 minute orbital time for objects at that altitude; 2) the re-entry trails of disintegrated satellites, hauntingly reminiscent of the Columbia Shuttle tragedy; 3) Clooney's calm-under-stress character (I know dozens of astronauts like that); 4) the stunning images from orbit transitioning from day to twilight to nighttime; 5) the Aurorae (northern lights) visible in the distance over the polar regions; 6) the thinness of Earth's atmosphere relative to Earth's size; 7) the persistent conservation of angular and linear momentum; 8) the starry sky, though a bit trumped up, captured the range and balance of an actual night sky; 9) the speed of oncoming debris, if in fact it were to collide at orbital velocity; 10) the transition from silence to sound between an unpressurized and a pressurized airlock; ... and 100) the brilliantly portrayed tears of Bullock, leaving her eyes, drifting afloat in the capsule.

Finally. There are issues you will be able to see throughout the movie but this is a movie that nerds should love. I keep wondering why people kept focusing on the small errors when it did so many things right.

User avatar
gmalivuk
GNU Terry Pratchett
Posts: 26818
Joined: Wed Feb 28, 2007 6:02 pm UTC
Location: Here and There
Contact:

Re: Gravity

Postby gmalivuk » Fri Nov 01, 2013 4:47 pm UTC

Because lots of us find it interesting and fun to notice errors and inconsistencies.
Unless stated otherwise, I do not care whether a statement, by itself, constitutes a persuasive political argument. I care whether it's true.
---
If this post has math that doesn't work for you, use TeX the World for Firefox or Chrome

(he/him/his)

infernovia
Posts: 931
Joined: Thu Jul 17, 2008 4:27 am UTC

Re: Gravity

Postby infernovia » Sat Nov 02, 2013 12:31 am UTC

A list of some inconsistencies that was there for the sake of cinema is cool, but I usually see it used as to validate nerd rage or a dismissal of an otherwise great effort (well, on the internet).

User avatar
raudorn
Posts: 370
Joined: Mon Jun 13, 2011 11:59 am UTC

Re: Gravity

Postby raudorn » Sat Nov 02, 2013 7:37 am UTC

I kinda agree with both sides. On the one hand, it is fun to look for things you know would work differently in real life. On the other, there's a time and place to do so and a movie shouldn't be judged on that merit alone (unless it's advertised as accurate...). I mean, I love SciFi as much as the next guy and just what is considered a giant among SciFi? The Hitchhiker. Yeah, "logical consistency" my shiny metal brass.

Speaking of which, wouldn't an expanding cloud of debris, which has a large volume after all, allow for a slightly eccentric orbit to intersect with the roughly circular orbit of the ISS only once per period? It doesn't need to be the exact same pieces that hit every time, so they might be hit by the center the first time and the edge the second time and the expanded edge the third time, etc. I mean, the whole movie is basically "Kessler-Syndrome: The movie". It's actually kinda realistic that a sufficiently large debris cloud would trigger more and more clouds that spread across the whole orbital range of LEO.

User avatar
gmalivuk
GNU Terry Pratchett
Posts: 26818
Joined: Wed Feb 28, 2007 6:02 pm UTC
Location: Here and There
Contact:

Re: Gravity

Postby gmalivuk » Sat Nov 02, 2013 7:52 am UTC

Who's judging it on accuracy alone?

Sure, *discussions* may focus on that, but only because it's more interesting to discuss than just agreeing about what they got right.

Also, while an orbit with higher eccentricity could intersect only once per period, the relative velocity would be far below orbital speed. The theoretical orbits like that that would have high relative velocity intersect the surface of Earth.
Unless stated otherwise, I do not care whether a statement, by itself, constitutes a persuasive political argument. I care whether it's true.
---
If this post has math that doesn't work for you, use TeX the World for Firefox or Chrome

(he/him/his)

User avatar
raudorn
Posts: 370
Joined: Mon Jun 13, 2011 11:59 am UTC

Re: Gravity

Postby raudorn » Sat Nov 02, 2013 9:12 am UTC

gmalivuk wrote:Who's judging it on accuracy alone?


Nobody. I wasn't accusing anyone, sorry if it that came off like a strawman.

I was thinking of a retrograde orbit, almost the same angle as the ISS, but with an angle difference shallow enough so the debris appears in the same 'ecliptic' plane as the ISS and the other objects in the movie, but wide enough so the cloud only intersects at the perigree. Of course the debris pieces have no attraction to each other, so sooner or later the cloud would disperse into lots of singular orbits depending on how fast the pieces are going. But for a few periods there should be sufficient intersection for collisions to happen.

User avatar
gmalivuk
GNU Terry Pratchett
Posts: 26818
Joined: Wed Feb 28, 2007 6:02 pm UTC
Location: Here and There
Contact:

Re: Gravity

Postby gmalivuk » Sat Nov 02, 2013 11:54 am UTC

A retrograde but more elliptical orbit would do the trick (same eccentricity would collide twice, wider orbit wouldn't have the same period), but then how did the debri get more than a 15km/s change in velocity?
Unless stated otherwise, I do not care whether a statement, by itself, constitutes a persuasive political argument. I care whether it's true.
---
If this post has math that doesn't work for you, use TeX the World for Firefox or Chrome

(he/him/his)

User avatar
tomandlu
Posts: 1111
Joined: Fri Sep 21, 2007 10:22 am UTC
Location: London, UK
Contact:

Re: Gravitar

Postby tomandlu » Sat Nov 16, 2013 6:19 pm UTC

Spoilers - do we need to add spoiler tags to film-threads once they're out, or can we just assume here be dragons?

Anyway, a couple of questions (loved the film btw - my 15 yr old son's response was "okay, no longer want to go into space")...

Spoiler:
My questions. Bullock's character twice holds onto an airlock door when opening it, and consequently suffers a nearly fatal jolt when the air pressure forces it open. In some ways, it's a nice acknowledgement of her amateur status (and presumably she metaphorically kicks herself the 2nd time). However, it was the one moment in the film when the physics looked glaringly wrong. I just didn't believe she could have possibly held on - it was just too violent. So...

Is it conceivable that she could have held on?

Wouldn't an airlock have a mechanism to drain the air out first by default? (this is a minor gripe - we're dealing with a disaster-scenario. Draining first could be the equivalent of "don't use elevators in the event of a fire").

Edit to add: The notion of the repeating collisions and the accessibility of the different space stations was clearly a huge stretch, but it didn't 'offend' me in the same way as watching a human being do something that looked glaringly impossible.
How can I think my way out of the problem when the problem is the way I think?

infernovia
Posts: 931
Joined: Thu Jul 17, 2008 4:27 am UTC

Re: Gravitar

Postby infernovia » Sat Nov 16, 2013 10:42 pm UTC

No. In reality, the gloves used by astronauts are not very grip friendly.

User avatar
charliepanayi
Posts: 1531
Joined: Sat Sep 27, 2008 7:26 pm UTC
Location: London, UK

Re: Gravitar

Postby charliepanayi » Sat Nov 16, 2013 10:56 pm UTC

Saw it in 2D, though I was tempted by 3D for the first time ever. I thought it was terrific, have seen it twice already.
"Excuse me Miss, do you like pineapple?"

"I don't want to achieve immortality through my work, I want to achieve it through not dying"

User avatar
headprogrammingczar
Posts: 3072
Joined: Mon Oct 22, 2007 5:28 pm UTC
Location: Beaming you up

Re: Gravitar

Postby headprogrammingczar » Sun Nov 17, 2013 12:10 am UTC

charliepanayi wrote:Saw it in 2D, though I was tempted by 3D for the first time ever. I thought it was terrific, have seen it twice already.


The 3D version is unquestionably better. See it a third time, it's worth it.
<quintopia> You're not crazy. you're the goddamn headprogrammingspock!
<Weeks> You're the goddamn headprogrammingspock!
<Cheese> I love you

User avatar
tomandlu
Posts: 1111
Joined: Fri Sep 21, 2007 10:22 am UTC
Location: London, UK
Contact:

Re: Gravitar

Postby tomandlu » Mon Nov 18, 2013 5:17 pm UTC

infernovia wrote:No. In reality, the gloves used by astronauts are not very grip friendly.


TBH It looked like you'd need to be Spiderman to have a chance, even ignoring the issue of the gloves. Ah well, a minor (but irritating) gripe.

And another thing...

When Clooney sacrifices himself, what force exactly is meant to be pulling him away? She'd already stopped him dead afaict, and if anything, he should have crashed into her. My assumption is that the ISS must have been spinning and centrifugal force was responsible, but I didn't notice the spin if that was the case. Was there any sign of the station spinning, or was this a mistake?
How can I think my way out of the problem when the problem is the way I think?

User avatar
Adam H
Posts: 1267
Joined: Thu Jun 16, 2011 6:36 pm UTC

Re: Gravitar

Postby Adam H » Mon Nov 18, 2013 5:28 pm UTC

tomandlu wrote:
Spoiler:
And another thing...

When Clooney sacrifices himself, what force exactly is meant to be pulling him away? She'd already stopped him dead afaict, and if anything, he should have crashed into her. My assumption is that the ISS must have been spinning and centrifugal force was responsible, but I didn't notice the spin if that was the case. Was there any sign of the station spinning, or was this a mistake?

Spoiler:
This really really really bugged me until I thought of centrifugal force.

I'm pretty sure they don't show any spinning, but I'm OK with it because if the background was spinning that scene would have a very different feel to it. Chaotic instead of sad. There's so much spinning leading up to that part there needed to be a calmness at the end.

Edited to add spoiler tags
Last edited by Adam H on Mon Nov 18, 2013 7:43 pm UTC, edited 1 time in total.
-Adam


Return to “Movies and TV Shows”

Who is online

Users browsing this forum: No registered users and 6 guests