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Inside the Spaceflight of 'The Martian'
benonemusic writes: Science writer Michael Greshko partnered with a team of scientists and engineers to explore the spacecraft and mission plans in The Martian (novel and movie), down to the rescue plan itself. Incorporating the help of Andy Weir, the novel's author, he comes up with a calendar of events for The Martian, explores the hazards of going back to save Mark Watney, and explains how a real world interplanetary spacecraft would pull off a rescue maneuver.
Not entirely impossible, just unlikely. There was a lot that could go wrong, and very likely to go wrong. The deceleration through blowing the airlock would most likely send Hermes spinning instead of decelerating, the opening not being a precise nozzle but a random hole directing the air outside at a random angle. The rocket would most likely be unbalanced after such heavy strip-down, sending it spinning again.
OTOH everyone overestimates the "one chance" they had at the encounter.
You're moving 12m/s away from the target.
To reach 12m/s at 2mm/s^2 you need 6000s or 100 minutes. That puts the target at 72km distance.
Now give it a chase. Accelerate for half of that distance, decelerate the other half. 6m/s top speed, average 3m/s relative speed. That's another 6.6 hours.
Mark would need to spend about 8 hours waiting for Hermes to smoothly make a perfect rendez-vous after failing the initial encounter. There's no time pression of time like with suborbital trajectory - they are both on escape trajectory. Hermes would get a little off Purnell Maneuver trajectory, but 72km offset and 12m/s error is practically nothing for this kind of mission. The whole panic was simply unnecessary.
45 5F E1 04 22 CA 29 C4 93 3F 95 05 2B 79 2A B2
Thanks for being the self-centered asshole who feels it's OK to fire up his phone screen in a darkened theater. Why should you have to bother to park your selfishness for 90-120 minutes and let the scores of other people see a movie in peace, right?
I just watched this tonight with a lady friend. I was bored enough to browse /. on my phone for a little while. Then she grabbed my hand and whispered that I'm supposed to be watching the movie.
Wow - you just casually admit to this? For the sake of others, please never do this again. There's a reason that theaters run the little public service announcements about turning off your phone before the movie. This should be a standard question on a test designed to identify sociopaths: "If you bored while watching a movie in a theater, do you a) suffer silently, b) leave the theater, or c) ignore the rest of the people in the theater that have paid to watch the movie and pull out your phone."