Poking holes in the "Gravity" trailer with NASA's help
arstechnica.com
arstechnica.com
(1) http://www.slate.com/blogs/bad_astronomy/2013/10/04/ba_movie...
SPOILERS BELOW:
The pivotal moment between Clooney and Bullock. They were both moving at 0 velocity relative to each other, yet somehow he's 'pulling' her away? Definitely not physically accurate how it's portrayed. A simple pull of any sort should have brought him her way. Was annoying to me that such a key moment was brought on by a physics inaccuracy.
I found the discussion about the recent failure with the water in the helmet thing more interesting. The weird thing is that in space you can drown in a half liter of water if you cannot get it to move away from your face. It is perhaps the scariest thought about a zero-g swimming pool where your own gravity pulls you into the center of a ball of water.
The sad part is, the technical points could have been fixed, they clearly had a lot of technical help. They just decided to ignore orbital mechanics completely and in fact I think that killed some of the tension. If you just have to line up, aim at the space station, and go, it's a lot less tense than if you actually have to figure out how to get there (see the incredible scene in Apollo 13 with the Jim Lovel siting out the window to get a re-entry trajectory).
SPOILER ALERT
Problem 1: debris - The debris were created after the space walk started by a chain of collisions began by a Russian anti-satellite weapon. So they could would not know to abort the spacewalk before it began.
Problem 2: Clooney's jetpack - The movie explains that he is testing an experimental jetpack that has very long duration. He could apparently set a spacewalk duration record while fly around almost continuously. Maybe this is impossible but the move seem to take place in the future, there is a Chinese space station, and/or alternate reality, the Space Shuttle still flies.
Problem 3: Clooney's Superman impersonation - As explained above this was a more advance jetpack than ever actually used by NASA.
Problem 4: Clooney's rescue attempt - Again the advance jetpack means it would make sense for her to rescue her.
The BIIIIIIG problem 5: From HST to ISS - Since it is an alternate and/or future world there is no reason orbits have to as they are today. It may even make sense to have the HST in a close orbit to IIS to make repairs such as this. And again the more advanced jetpack would make such a journey easier.
Problem 6: Suit abuse - Here I think the article may have a good point seems like the suits would not be able to take all the damage.
Err... there is a Chinese space station: http://en.wikipedia.org/wiki/Tiangong-1
The Chinese space station portrayed in the film is Tiangong-8. Not number 1.
Thus, the movie takes place in the future. Actually, too far into the future. The Chinese are currently planning to launch their modular space station as Tiangong-3. They're not planning to go through 7 Salyuts first.
Wait, are you suggesting they could/would _change_ the orbit of the HST or ISS? That seems... awfully unlikely. (It would be crazy expensive to change the orbit once the thing is up there)
On the other hand, of course, there are no more shuttle flights in reality, so, yeah, it's some kind of 'alternate future' (more like 'alternate present'! which I guess is what fiction is, after all). In this version of the present/future, they still fly shuttles, and originally put the HST and/or ISS in completely different orbits than in our actual present.
Um, okay, I guess.
But really, let's just say there are several major physics inaccuracies neccesary to make the story, but it's still a movie that gets many many of the details of actual astronauts and space equipment right.
I think it's funny that after dismissing major physics failures, you get stuck on suit abuse. Hey, in the alternate present of the movie, they obviously invented much stronger suits, right? :) If they've invented a jetpack that somehow has enough propellant for much more delta-v than seems possible, then they can clearly invent a spacesuit that is stronger than seems possible too!
(Me what I'm still wondering about but havne't seen comments on, is if there's any plausible scenario where the space debris could be in an orbit where it would collide with them every 90 minutes... this seems unlikely to me even if they stayed in one place, let alone the every 90 minute period that somehow covers both the shuttle and the ISS and the chinese space station!)
It just seems like their space suits had to endure lots and lots of abuse. Not sure why they would be designed for this even in the future/alternate reality. Seemed believable but just barely.
Not sure which "major physics failures" I dismissed - the long lasting jetpack? You can get much much greater energy densities using something other than the ultra safe compressed nitrogen in previous jetpacks.
The ISS orbits every 93 minutes and the Hubble every 96-97 minutes[1][2]. If the debris cloud was geosynchronous, as most communications satelites are, it would make sense that they might pass thru every 90 minutes or so. Not sure if this makes sense given different orbit heights.
Overall I am quite impressed how very realistic this movie was while still being very entertaining.
[1] http://en.m.wikipedia.org/wiki/International_Space_Station
The movie was utterly stunning. Just go see it.
First, they don't have their visors (those Sun protective, gold plated ones). I'm not sure, but I guess that's a big no-no on EVAs, having the Sun enter your field of vision so close to it (in Earth's orbit) would probably do some eye damage. Again, I'm not sure the visor is always mandatory but I don't remember seeing any photos of actual EVAs without it being down.
Second, Sandra Bullock rotating while attached to Canadarm... My impression was that the g force would be too high for her to stay conscious, or able to communicate. But it turns out intuition was wrong on that one: back of envelope calculation gives ~3 g (assuming 15 m length for the Canadarm [assuming it is the Shuttle Canadarm], but it was slightly retracted so it would be less, and a period of ~4 s) while still attached to the Shuttle, and ~1.5 g when the arm broke off (~3 m radius, 2-3 s period). So, that's OK. :)
Third, the abuse those suits were getting! That's just crazy. At that point I got so annoyed that I didn't bother to notice all the other stuff the article talks about.
Now I'm just bummed out that all this might have spoiled the movie for me (I tried not to read the plot section on Wikipedia, but got a glimpse of the ending as I was scrolling). Nerd rage is a horrible thing. :)
I noticed some flaws, but for a Hollywood movie they were using "comic book physics" which most scifi movies and TV shows use.
I assume that it takes place in an alternative universe where NASA didn't scrub the Space Shuttle program, and space stations are placed close to each other as some form of disaster planning, and of course commercial companies like Space-X and Virgin Galactic didn't exist.
I kind of thought it was like "The Net" but instead of running from the police and computer hackers, she was trying to escape from space and get back to Earth. :)
Anyway my son and his girlfriend saw it and loved it, and both decided to take astronomy because of it. They are both freshmen in high school taking physical science. I think the movie was meant for them. I had to explain after the movie how in space there is no air, and the space capsule parachute was tangled on the ISS and she had to cut it free. That it wasn't because it would slow down the capsule but that it had tethered it to the ISS. That if the chute was free there'd be no air to slow it down. They thought there was something in space the chute would slow it down on, but I told them it was a vacuum. Chutes only work in the atmosphere. That the friction of reentering the atmosphere is what had caused the heat that was burning up the other capsule she had to get on the Chinese station.
Some spoilers Warning
Let me see, Explorer Space Shuttle trying to repair a telescope with a new circuit board. Russians go crazy trying to blow up out of control spy satellite with some super missile that just wipes out all satellites and throws debris everywhere. NASA was not aware of it, and had miscalculated the velocity of the debris so there was no way to abort the mission before they got hit. Some super space suit thruster pack got George Cloney to fly around like Superman and save Sandra Bullock and get to the ISS. But the ISS has problems and the Russian space capsule has a deployed parachute in space. Bullock gets snagged on parachute cord, Cloney has to let go to save her or else she'll get lose. She has to use Russian capsule to get to the Chinese station that has a clone of the Russian capsule with a working parachute to get back to Earth. I won't say how it ends though.
Sure it was mostly animation for 90 minutes, and we saw it in IMAX. But the main point is that it gets teenagers to study more math and science as a result of seeing the movie and asking questions about the physics involved. So I can forgive the mistakes and "comic book physics", if it promotes education.
Not sure I can cope with two hours of sandra bullock trying to grab hold of stuff regardless of the physics...
http://www.digitalspy.com/movies/news/a521285/james-cameron-...
I think if you saw it on a smaller screen you would come away less enthused. I thought there were definitely plotting and script problems, but that the visual impact of the film compensated for that. Sandra Bullock is definitely not the best choice, but she's not terrible (I don't think she was Alfonso Cuaron's first choice either).
According to Wikipedia, Angelina Jolie was the first choice, but in my opinion that would have been a much, much worse choice. What's wrong with Bullock? To me she seems plausible as an astronaut at least as far as physique and appearance go.