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Watched Elysium yesterday, it's not that bad of a movie, i expected something worse.
So, while i watched it i was asking myself if the space flight in that movie was possible. You know they just take off from Earth and then reach the orbiting Elysium in a straight line. So i guess Elysium is synchronized with the Earth so it keeps relative to the same spot to the ground, in that case i'm assuming -but i don't really know- it would be possible for a ship to behave as in the movie: just point at the big thing in the sky and go full throttle. But then again, for Elysium to be synchronized like that with the Earth it should be pretty far away from it, according wikipedia it is like 35.000 km high but they seem to get there very fast and don't even sit down while exiting the atmosphere! At that speed shouldn't they have a hard time not breaking their bones against the walls? I find it hard to mantain balance in the bus!
Another thing is that Elysium has it's own atmosphere with an open sky in that station. Something like that is even plausible, has ever been studied to do it in the future?
It just looked weird from my point of view, but then again, my only "knowledge" of physics come mostly from KSP so i don't know, maybe it is accurate.

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1 hour ago, Wonky kergineer said:

You know they just take off from Earth and then reach the orbiting Elysium in a straight line

Go just straight up to destination is possible if you have the TWR and DV required now it's certainly nothing like what is shown in the movie as it require an hard acceleration and you still need to match relative velocity with your station.

1 hour ago, Wonky kergineer said:

Another thing is that Elysium has it's own atmosphere with an open sky in that station. Something like that is even plausible, has ever been studied to do it in the future?

If the station have a good artificial gravity (via it's own rotation) why not but the atmosphere will eventually leak anyway so for a small station, it pretty is a bad idea. Most concept of station like the one in the movie I know of all have a roof (transparent one to make it more cool)

I haven't seen the movie i'm judging by your description and google

Edited by Hary R
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Have you seen the xkcd "time vs. understanding of orbital mechanics" yet?  Most people aren't up to the level of "high school physics" yet (and easily well behind Randal Monroe-types before HS physics at that).  Guess who buys Hollywood tickets?

Things I didn't understand about orbits before KSP:

Escape velocity != infinite distance.  Escape velocity gets you <=2AU distance from Earth, maximum (you're orbiting the Sun at 1AU until you spend more delta-v).  Even Scott Manley blew this in an early KSP video (of course,  I don't think KSP included Kerbol in that one, so technically he was "right").

How to get to Mars (and any other planet).  Yes, I *knew* about Keplar's laws, I just didn't *get* that you needed to burn (once) to a new ellipse and map it onto the trajectories of Earth and Mars (then capture).  That was pretty obvious, in retrospec.

That nearly all (0th order mechanics) could be summed at "burn at perigee: raise apogee".  Once you learn that, all else are details.

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If the target is in Geo and you launch straight up at it with your Pe the altitude of the station I don't see why it wouldn't smack you in the face at the speed the Earth's surface rotation would be at that altitude. Straight up =/= rotational velocity. Eventually you'll need to add a little horizontal velocity.

Edit: I can't imagine this would work for a space elevator either.

Edited by WestAir
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26 minutes ago, WestAir said:

If the target is in Geo and you launch straight up at it with your Pe the altitude of the station I don't see why it wouldn't smack you in the face at the speed the Earth's surface rotation would be at that altitude. Straight up =/= rotational velocity. Eventually you'll need to add a little horizontal velocity.

Edit: I can't imagine this would work for a space elevator either.

But it's in LEO, not GEO- somehow.

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http://xkcd.com/1356/

For most people, their graph of this would see a sharp drop every time they saw a Hollywood "sci-if" like Elysium. 

Its movies like that that lead people to believe that going to space just involves going up, where gravity magically disappears. The same reason that laypersons actually think that blue origin's new Shepard can compare to spacex's falcon9. Shameful. 

Edited by Apexazimuth
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