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MikeJF posted:The whole thing was that they needed a heavy rocket. There were plenty of normal rockets hanging around. We launch about two a week. But to get an appreciable mass to Mars rapidly you'd need a heavy. If we're nitpicking the movie, they used stock footage of present-day boosters for the launches from Earth. The first attempt at sending supplies (the one that blew up) was pretty clearly an Atlas V, a 541 or 551 variant I think. The Chinese booster looked like a Long March, probably a 2 or 3. Also, the launch they see on TV in the epilogue is obviously a Delta IV Heavy. These are all among the heaviest lifters available today, and perfectly capable of throwing something to Mars -- the Curiosity rover rode on an Atlas V, for example. They're also fairly common as boosters go, and there are usually several of them in the pipeline at any given time. But would they be capable of throwing something heavy enough during a not-very-good launch window to Mars? No idea. I guess it'd depend on the mass of the resupply probe and the exact orbital dynamics, and even the book didn't go into THAT much detail.
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Oct 5, 2015 19:08
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I think part of the problem that was being presented in the movie wasn't just getting escape velocity and a trajectory for Mars insertion during a bad launch window, but having a lot of excess velocity to get there sooner because time was critical with Watney slowly starving to death. I mean, clearly they could get things to Mars; Ares III was the third manned landing. Another nitpick I had was the nerdy math guy explaining a gravity assist to the director of NASA as though he were a child. Nail Rat fucked around with this message at 19:16 on Oct 5, 2015 |
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Oct 5, 2015 19:12
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ImpAtom posted:Modern space travel is so depressing. Nah. We are in a lull period of buildup right now. What is actually going on is amazing. We aren't presently running anything on the scale is the Saturn V or Energiya, but our regular heavy lift stuff (not the flashy space shuttle or anything, the actual workhorses that put things up and establish industry and make money) are the next tier down, doing more than the shuttle could. We have a Saturn equivalent with partial reusing kitty due to make its first flight next year (Falcon Heavy) which will go into production as our regular satellite lifter, giving us the most orbital capability we have ever had. The NASA SLS is going to have even more capability than the Saturn did and is due to roll off lines and start flying in 2022 These won't be one offs either - the Falcon Heavy is backed by the NRO, the most aggressive user of satellites out there. You'll see congress cut aircraft carriers before you see them cut the NROs spy sat budget. We've been doing some crazy stuff with our orbital dynamics too, with putting out satellites in higher and stranger orbits to protect them from a Kessler cascade - we put our communications satellites in Molniya orbits these days for example We have a private company (Moon Express) putting their own probe on the moon in 2017 The newly announced engine out if University of Sydney has an isp of a whopping 14,600 seconds, almost double that of HiPeP (previous record holder at 9,600 secs) NASA has a new spacesuit design (the one in The Martian is made to look like it) that deals with many of the previous handoffs between hard shells and soft suits so now there is no pre-breathing required and can be rapidly donned alone Our probes, satellites, and manned orbital capabilities are seeing quantum leaps in improvements from new manufacturing techniques and it hardware. We have more entities doing the lifting than ever before with a more reliable and larger funding stream than ever before that can put more in space than ever before, put it in newer places, faster, than ever before, and once it is there it is able to do more than we ever could have imagined even 10 years ago.
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Oct 5, 2015 19:26
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Nail Rat posted:I think part of the problem that was being presented in the movie wasn't just getting escape velocity and a trajectory for Mars insertion during a bad launch window, but having a lot of excess velocity to get there sooner because time was critical with Watney slowly starving to death. Also with how such a thing as gravity assist would need to be kept under wraps as this totally radical weird thing nobody had ever heard of or believe.  That was another part of it that made NASA look really stupid, IMO. In real life, using a gravity assist to send the parent ship back to Mars would have been one of the first things thought of and thus on their list of options when deciding what to do, so it being presented the way it was made it seem like NASA is run by a bunch of nitwits. Also, as a chemist I laughed out loud at his water-making apparatus. First of all, his contraption would have leaked incredibly toxic hydrazine vapor, killing all the plants and Watney together. Second, hydrogen burns with a colorless flame, so the big yellow torch was absurd. Third, it was all completely unnecessary as hydrazine will burn with oxygen directly to make water vapor and nitrogen, so there was no need of it in the first place.
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Oct 5, 2015 19:27
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My weird thing is how it was always snowing at the Chinese space center. Both when it is introduced and after the 7 months later cut, still all cold and grey with a light dusting of snow. Particularly since I think that was supposed to be Beijing, not Jiuquan (not that it would make a lot of sense to always be snowing year round in the middle of the Govi desert either)
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Oct 5, 2015 19:31
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To be fair, it actually was a fairly risky and unconventional plan. Mostly due to the fact that they would only be doing a flyby of earth and have only one shot to intercept the supply vessel that would allow them to not starve to death. If launch had to be scrubbed for another day, they'd have died. Of course, this also begs the question of how the hell they were able to rendezvous with it when they were supposedly traveling at an extremely high velocity. Really while it's a lot more realistic than Interstellar, I guess it's best to not think about the science too much.
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Oct 5, 2015 19:34
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Nail Rat posted:Of course, this also begs the question of how the hell they were able to rendezvous with it when they were supposedly traveling at an extremely high velocity. The big booster brought the probe up to the same velocity as the ship.
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Oct 5, 2015 19:39
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Deteriorata posted:IMO it made NASA look pretty drat stupid. That's the one thing the author made up intentionally to establish the story.
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Oct 5, 2015 19:41
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old dog child posted:That's the one thing the author made up intentionally to establish the story. He needed to find some other way to establish the story if he was going to make it about Mars. Something like a micrometeorite strike causing the lander to start leaking fuel, meaning they had to launch in 10 minutes or all of them would be stuck there - while Watney was off on some remote mission and incapable of getting back in time. That's at least moderately plausible and gives an even better ethical dilemma to start the film with. As it was, any suspension of disbelief was destroyed the instant the film started.
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Oct 5, 2015 19:48
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You're sperging very hard
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Oct 5, 2015 19:54
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How are u posted:The China bit was still a complete slob-job, however. I really don't understand this at all. Like, should they have instead had them go "hah, loving China man, who needs loving international cooperation, America gently caress YES" or something? The China thing is literally in the book, it wasn't added to the film at all.
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Oct 5, 2015 20:03
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I didn't have much of a problem with the storm causing the damage it did, to be honest. It did a good job of jump starting the plot and also gave us the great scene where another storm was threatening to tear down Watney's half-assed repair of the broken hab. I think the Martian succeeds as a largely accurate scientific movie, and hopefully it will get some kids interested in engineering or space sciences that otherwise wouldn't have been.
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Oct 5, 2015 20:04
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Nail Rat posted:To be fair, it actually was a fairly risky and unconventional plan. Mostly due to the fact that they would only be doing a flyby of earth and have only one shot to intercept the supply vessel that would allow them to not starve to death. If launch had to be scrubbed for another day, they'd have died. Of course, this also begs the question of how the hell they were able to rendezvous with it when they were supposedly traveling at an extremely high velocity. Really while it's a lot more realistic than Interstellar, I guess it's best to not think about the science too much. Because it's relative velocity that matters. Put the supply pod on the correct velocity (remember that velocity is both d/t and a vector) and it's easy peasy to catch
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Oct 5, 2015 20:39
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Deteriorata posted:He needed to find some other way to establish the story if he was going to make it about Mars. The film is actually better about it than the book, talking about the force of the wind rather than the wind speed. Of course to get that force you are talking something like the Great Red Spot on steroids on Mars, but it isn't the blatant problem like in the book. And the super tornadoes we see in the background would be consistent with the insane storm If anything the bigger science flub was the end with the EVA suits. Soft suits are at lower pressure (and higher oxygen concentration) than the atmosphere so they are usable, so Lewis would have needed to pre-breathe for at least 30 mins to get in one without getting the bends. Same with Watney, though you could hand wave him taking Vicodin so he could do it despite the pain. That still leaves him punching a hole in the EVA suit. Internal pressure being lower than normal (and normal only being 14.7 psi) means it would have very low velocity, and a low mass flow rate means low thrust. Even with a puncture that small he'd still die in ~90 seconds Still, really enjoyable film
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Oct 5, 2015 20:45
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Nail Rat posted:To be fair, it actually was a fairly risky and unconventional plan. Mostly due to the fact that they would only be doing a flyby of earth and have only one shot to intercept the supply vessel that would allow them to not starve to death. If launch had to be scrubbed for another day, they'd have died. Of course, this also begs the question of how the hell they were able to rendezvous with it when they were supposedly traveling at an extremely high velocity. Really while it's a lot more realistic than Interstellar, I guess it's best to not think about the science too much. Remember that the rocket they used had the delta-v to get to get the supplies to mars by itself, so it could definitely catch up with the hermes. Also, making the launch date isn't really a huge issue. They can launch months ahead of plan and just have the probe sit in orbit until the hermes gets there. Though, thinking about the rescue plan, why didn't they just over burn on their budget to make the intercept with the mav and then do the atmosphere trick later on to make intercept with earth rather than do everything all at once by the seat of their pants?
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Oct 5, 2015 20:52
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Fried Chicken posted:The film is actually better about it than the book, talking about the force of the wind rather than the wind speed. Of course to get that force you are talking something like the Great Red Spot on steroids on Mars, but it isn't the blatant problem like in the book. And the super tornadoes we see in the background would be consistent with the insane storm Yeah, it was largely enjoyable. It's still science fiction and Hollywood, so I know not to look too closely. The ending was standard Hollywood. Just a launch, rendezvous and capture would be too boring. It's just that one of the big selling points with this one was its supposed scientific accuracy, and to start it off with something so completely absurd was rather off-putting. Like starting a film set in the Sahara with a flood as the primary plot device or something. We know way too much about Mars to get away with stuff like that. Anyway, I'm done bitching about it. The science was far worse than I had been led to believe, so I was kinda pissed but I'm over it.
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Oct 5, 2015 21:01
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ImpAtom posted:In the book it's just straight-up a design defect that got overlooked and would have been meaningless on a regular operation. One of the seams was bad IIRC. Which, okay, pretty much describes the structure of this film to the tee. 
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Oct 5, 2015 22:37
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Deteriorata posted:It's just that one of the big selling points with this one was its supposed scientific accuracy, and to start it off with something so completely absurd was rather off-putting. Like starting a film set in the Sahara with a flood as the primary plot device or something. We know way too much about Mars to get away with stuff like that. It being some bullshit that nobody could possibly have expected to ever happen on mars goes a long way to explaining why it caused a total scrub of the mission, though.
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Oct 5, 2015 23:39
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Dr. Stab posted:Though, thinking about the rescue plan, why didn't they just over burn on their budget to make the intercept with the mav and then do the atmosphere trick later on to make intercept with earth rather than do everything all at once by the seat of their pants? Yeah, that was a lot clearer in the book. Those maneuvering jets were the highest-thrust engines they had -- their main engine was an electric thruster with a teeny tiny force but which could run basically forever. It's made for big slow accelerations lasting months. Great for going between planets, useless for sudden moves. Hence the maneuvering jets. But even using 80% of the fuel for those jets, they could still only change their angle of flight just enough to intercept the MAV after coasting on that new course for forty minutes (or whatever it was). So now they would pass by closely enough, but still with way too much speed. The other 20% of their maneuvering fuel wouldn't have been anywhere near enough to slow them down for a proper rendezvous. What they needed was a big sudden push to slow them down right before rendezvous, none of their engines could do that, hence the unconventional seat-of-the-pants idea.
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Oct 5, 2015 23:41
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The idea that the China subplot is pandering is a bit weird considering the rest of the film is a long love letter to NASA and American sensibilities of discovery and exploration.
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Oct 6, 2015 00:33
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Ravel posted:The idea that the China subplot is pandering is a bit weird considering the rest of the film is a long love letter to NASA and American sensibilities of discovery and exploration. Not to mention, since it originated in the book, it's not like Andy Weir wrote it to cash in on that booming Chinese ebook market.
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Oct 6, 2015 00:43
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The author added the China subplot because he needed someone to provide an additional booster and private space companies weren't a thing (or as much of a thing at least) when he first wrote it. He said that if he were to write it today then the booster would have probably come from someone like SpaceX instead.
Senjuro fucked around with this message at 10:01 on Oct 6, 2015 |
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Oct 6, 2015 00:46
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What about the American sensibility of international cooperation and mutual benefit? That's a thing, right? Oh yeah, and it's pandering the the Chinese if they aren't loving assholes? It's more detailed in the book I guess, but they are not only in it out of the goodness of their hearts but it is also a political and scientific gain for them as well. They get a dude on the next Ares mission too!
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Oct 6, 2015 00:50
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I think its important to note that most of the plot points everyone is harping on were the result of a dude with limited writing experience writing a Science Mary Sue Novel. It's cool and I liked it but its by no means anything above a pulp novel.
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Oct 6, 2015 02:04
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Jago posted:What about the American sensibility of international cooperation and mutual benefit? It's pandering because they want this movie to rake it in in the Chinese market. Which it hopefully will. I'd love more space movies.
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Oct 6, 2015 03:21
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I have exactly one quibble with the film: When the title card comes up that says "The Hermes." Proper names don't get definite articles--that's why everyone wasn't going around asking about the status of The Mark Watney being stranded on The Mars.. The film writers knew this, because later, when another title card came up "Pleiades," it didn't have a "the".
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Oct 6, 2015 03:55
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Madurai posted:I have exactly one quibble with the film: Yeah but The Enterprise Sorry, space film tradition.
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Oct 6, 2015 03:59
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MikeJF posted:Yeah but The Enterprise Spoken is fine, that's colloquial use. You don't put that poo poo in lettering, though.
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Oct 6, 2015 04:02
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How are u posted:It's pandering because they want this movie to rake it in in the Chinese market. Which it hopefully will. I'd love more space movies. The exact plot is written in the book. He wasn't writing for the Chinese.
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Oct 6, 2015 04:20
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So I've got a question that I'm pretty sure I'm just dumb and missed: After he loses the potatoes but still had some left, why couldn't he just build a new farm? Was the actual HAV unit destroyed? For some reason I thought it was just the airlock, and he could set up a new farm with some potatoes. A bit of a gamble, maybe, but...
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Oct 6, 2015 06:48
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SavTargaryen posted:So I've got a question that I'm pretty sure I'm just dumb and missed: He lost the fertile soil that allowed the potatoes to grow.
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Oct 6, 2015 07:02
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SavTargaryen posted:So I've got a question that I'm pretty sure I'm just dumb and missed: All the potatoes died when the hab breached and they were exposed to subarctic cold and near-vacuum for a day or so. Any potatoes he had would still be edible, but they sure wouldn't sprout anymore after that. (Also, the bacteria in the soil died too, but the movie doesn't call that out.)
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Oct 6, 2015 07:02
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SavTargaryen posted:So I've got a question that I'm pretty sure I'm just dumb and missed: efb Anyway, I enjoyed it well enough after having read the book just a month or so ago. Of the things glossed over or omitted from the book, I didn't like the loss of the difficulty on the rover modifications, the storm and roll over on the drive, and the pathfinder frying. But they had to fit it into a movie run time so whatever. I had hoped the movie would be really good and improve on the weaknesses of the book, but it didn't quite rise to that level for me, though I still enjoyed it. bawfuls fucked around with this message at 07:14 on Oct 6, 2015 |
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Oct 6, 2015 07:09
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Like I suspected, I'm dumb and missed something! Good movie, though. I really, really enjoyed it. The video logs being his way to blow off stress was magnificent. Edit: Also now I need to rig up something to expose my potatoes to a vacuum because the fuckers keep sprouting within like two days of Louisiana heat. This is a good use of my time.
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Oct 6, 2015 07:41
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Nail Rat posted:To be fair, it actually was a fairly risky and unconventional plan. Mostly due to the fact that they would only be doing a flyby of earth and have only one shot to intercept the supply vessel that would allow them to not starve to death. If launch had to be scrubbed for another day, they'd have died. Of course, this also begs the question of how the hell they were able to rendezvous with it when they were supposedly traveling at an extremely high velocity. Really while it's a lot more realistic than Interstellar, I guess it's best to not think about the science too much. They would not all have died though even if they missed the supply rendezvous and any second attempt. Cannibalism would have come to rescue! The book does a good job explaining how some suicide pills and creative cooking would have allowed a Hermes crewmember to make it.
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Oct 6, 2015 11:11
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My understanding is that the movie is good but leaves out a lot of great details from the book. With that in mind, would I be better off reading/listening to the audio book?
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Oct 6, 2015 12:02
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Josh Lyman posted:My understanding is that the movie is good but leaves out a lot of great details from the book. With that in mind, would I be better off reading/listening to the audio book? Senjuro posted:Saw the movie last night and now I get to be one those guys that tells everyone that the book was better. The things that made the book popular, the in depth science and engineering details and the clever and creative problem solving, are almost completely gone. The constant feeling that Mark has to keep using every bit of ingenuity in him to keep on surviving is just not there. I'd only recommend the movie if you think you can enjoy the same story but without those elements in it. Also the movie spends a much larger percentage of time with the Earth characters than the book does which really undermines the strong sense of isolation you're supposed to feel when it focuses on Mars. So it really depends on how important engineering porn is to you.
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Oct 6, 2015 13:27
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Senjuro posted:Well if you ask me: Audiobook it is.
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Oct 6, 2015 13:38
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Senjuro posted:The constant feeling that Mark has to keep using every bit of ingenuity in him to keep on surviving is just not there. Yep, definitely an opinion that should be taken seriously by people and not mocked or anything.
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Oct 6, 2015 13:49
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Read the book first, really liked the movie. I thought it looked great, visually with the helmet-cam stuff and shots of Mars. I agree with the people saying that his peril wasn't really felt as much in the book. It seemed a little too much in the real of a positive, happy story (which I guess it is) but the overall tone did seem to unbalance towards being cheery, rather than touching more on how hard he was fighting to survive. Really like it anyway.
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Oct 6, 2015 14:04
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