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YA fantasy novel set 350 years in the future under a corporate dictatorship which reanimates dead people to use as disposable slave soldiers.

So the setup is a medical/research station orbiting a planet. The shuttles used to come and go have been stolen. Four recently reanimated, cryogenically preserved kids, and a dog, are stuck on the station and want to escape. Their plan is to crash the station into the planet.

The station has some basic steering/engines/directional propulsion normally used for orbit decay correction but isn't really designed for re-entry other than being strong enough not to totally come apart if it falls out of orbit so it (and its tech) can be salvaged.

The kids have access to the station's anti-grav system and the cryopreservation tank that they came out of. The way I'm thinking of doing it now is to have them hack the station to sabotage the orbit co-ordinates and activate the anti-grav. Refill their cryotank with water and get back in it (breathing kit of some cool futuristic nature - with something figured out for the dog) and close it on themselves (one of them is phobic of drowning because that's how he died so that makes for extra drama) riding out the crash in submerged zero-g.

So my question is... do you think it's
a) good reading/cool drama?
b) plausible in fiction/worldbuilding terms?
c) not cheating the unspoken rules of suspended disbelief?

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    $\begingroup$ a) It's a bit short but I guess so. I would maybe spend more time introducing the characters to make the reader care. b) I'd love to hear more about that undead dog and children army, but that definitely sounds like fiction to me c) I've recently watched some Star Trek DS9 and in comparison everything makes sense. I've also seen the Star Wars Force Awakens and since that made money, it's pretty clear that people shouldn't worry about outdated things like a story and world building anymore and more about marketing. $\endgroup$ – Raditz_35 Sep 4 '17 at 13:04
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    $\begingroup$ Don't worry about it. The rest of the plot is totally orthogonal to reality. $\endgroup$ – Donald Hobson Sep 4 '17 at 13:27
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    $\begingroup$ While sending your characters into the water may sound like it would be soften the impact, it probably increases the likelihood of their death. Water is incompressible, and at the velocities of impact it will act like a solid. As such, it will transfer the full force of the crash through their bodies and they will die. Google the beer bottle water trick. $\endgroup$ – sdfgeoff Sep 4 '17 at 19:43
  • $\begingroup$ It's not solving the question of surviving a crashing space station, but assuming the anti-grav works on emitters you could attach them to an escape pod, fire it out in such that it'll land on Earth, then use the anti-grav generators to slow the descent down to survivable speeds. $\endgroup$ – SGR Sep 5 '17 at 9:53
  • $\begingroup$ Why don't they escape with the lifeboat instead of crashing the station? $\endgroup$ – mouviciel Sep 5 '17 at 13:02
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Space is not far away, staying there requires you to go really fast.

As is often mentioned, the problem with atmospheric re-entry from orbit is not the distance you have to fall but the speed you have to lose.

First you need to drop orbital speed to something approaching almost nothing without hitting the atmosphere, then you need to survive the landing. If you don't drop from orbital speed you won't survive re-entry. Since you have an anti-grav system that can be MacGyvered to keep you in orbit, then used for a controlled landing. The question is whether you can get round using small maneuvering thrusters to dump that much speed.

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    $\begingroup$ terminal velocity is likely lower for the kid than the station, so if he has decelerated his best bet is exits the station and fall on his own. unless the station was designed with a crash in mind it is like putting an egg in a safe and dropping it off a cliff and expecting the egg to survive. $\endgroup$ – John Sep 4 '17 at 15:00
  • $\begingroup$ I like fall on his own! If they are zombies they could do it. $\endgroup$ – Willk Sep 4 '17 at 19:44
  • $\begingroup$ You'd want to use the atmosphere to reduce your orbital as much as possible through aerobraking. If you reduce your orbital speed to 0 outside of the atmosphere gravity will accelerate you straight down and you'll impact the Earth at speeds well beyond terminal velocity. On the other hand If you enter the Earth's atmosphere at the right angle the atmosphere can give you enough acceleration against gravity so that you only impact ground at terminal velocity. $\endgroup$ – Ross Ridge Sep 5 '17 at 0:37
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    $\begingroup$ @RossRidge, there's an anti-grav system to macgyver into descent control. Aerobraking is far more dangerous in a vessel not designed for re-entry. $\endgroup$ – Separatrix Sep 5 '17 at 7:07
  • $\begingroup$ @Separatrix Since the vessel isn't designed for reentry and its propulsion systems are only designed for station keeping, there's no reason for the anti-grav system to be powerful enough to arrest the station during a straight down decent. On the other hand vessel is designed is not to break up on re-entry, so areobraking isn't a problem. Entering the atmosphere normally through a standard reentry approach is far more safer then going straight down. $\endgroup$ – Ross Ridge Sep 5 '17 at 14:01
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Zombie kids! I love it! There is an infinite amount of crackingwise about being zombies that can move things along.

I like your scheme except for one thing: imagine the movie. Re-entering the atmosphere, the ship glowing hot, falling apart around them and they are hiding in a wet closet comforting their scared friend. A wasted action opportunity.

My humble proposal:

They have cryo tank, cryo juice, water (apparently), anti gravity, space station, dog. On the way down they cool the station and slow it down by dumping the water out the front where it turns into steam. When that runs out they dump the cryo juice. The ship is falling apart around them. They pull the empty cryo tank on top of an antigravity pad, pile in and fly it out the top of the disintegrating station - or actually the station falls out from under them.

Then they watch the falling station from their airship eight miles up. They put up a sail for propulsion. It can be the good ship More Brains.

"It should be really cold up here."

"It would be, if we weren't zombies."

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Your problem is that with traditional, present-day technology, to stay geostationary, the station has -- depending on its altitude -- a speed of something like 10,000 km/h (this is the speed of a "typical" sattelite at 35-36,000 km). That's because we cannot nearly afford the amount of energy that it would otherwise take to keep the station "up there".
If you decelerate, the station will approach and finally drop to earth, which isn't so much a problem per se (except at the very end), but it will enter the atmosphere with a velocity of, say, 5,000 or 6,000 km/h. Which, as you can imagine, is not precisely cool (pun intended) for an object that isn't explicitly built to withstand that abuse.

Now, you state that there is an antigravity device of sorts. This suggests that you do not really need that speed. It is likely that the space station will still have a high velocity since that costs close to zero whereas keeping an antigravity device powered for years will needlessly burn a lot of energy. It does, however, not have to be that way.

Thus, what the zombie kids would need to do is program the correction engines to gradually halt the station, and simultaneously turn up the antigravity device so the station stays (at least for the most part) in equilibrium. It needs not be a perfect equilibrium, the station can indeed start dropping immediately. The descent however needs to be slow enough so the manueuver engines have enough time to reduce velocity enough so the station isn't torn apart by turbulences or burns to ashes entering the atomosphere (in fact, for a more interesting story, the station probably should be torn apart, at least partially).
Then, gradually reduce the antigravity device's output, and float to the ground.

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  • $\begingroup$ Most space stations would not geostationary but more than likely Low earth orbits. $\endgroup$ – Old_Fossil Sep 12 '17 at 6:21
  • $\begingroup$ @resident_heretic: Maybe so, but stable low orbit velocities are somewhere between 25,000 and 28,000 km/h. That's not really much (or any) better for surviving the re-entry :-) $\endgroup$ – Damon Sep 12 '17 at 9:34
  • $\begingroup$ Would make one hell of a dent. LEO orbits are for logistical concerns such as resupply mission. If a geostationary were to de-orbit it would hit the Earth atmosphere at such a bizarre angle that it would bounce off and go out in open space averting destruction and moving on inertia alone and if by bizarre chance if the orbits happen to sync up the space station eventually crashes in Mars...... :)- Gotta stop drinking coffee at night. $\endgroup$ – Old_Fossil Sep 27 '17 at 6:08
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If you have "anti-grav" you're probably not going to be crashing the station, but if you did crash it the biggest survival issue isn't the fall it's the stop at the bottom. Water as a deceleration cushion is doable, kind of, sort of, but can the container survive the impact and how much of the g-force of landing does it absorb before failure? Anything it doesn't absorb is passed on to the occupants, if the passed on load is above about 50 gees it is going to be injurious at a minimum.

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Before you start you need to take an extra cloth, and/or clothing or whatever you can find to make parachutes. Clothing dispensers are probably semi automated so you can probably trick them into giving you clothes made out of suitable material. I need vinyl/canvas for a size XXXXXXXXXXXXXXXL person go! Either that or just stitch smaller ones together. You might be able to get some material from beds or other areas of the ship.

Using the similar technique you might be able to fashion a hot air balloon, I am sure you can find something to heat the air with in the kitchen or maintenance area.

Harder, but possible doable a homemade blimp. Using the similar materials, and breaking the water into hydogen and filling the blimp with that should give you enough lift to touch down gently.

Hang glider might actually be easier, depending on what materials you have to work with.

The only trick is knowing when to eject.

Once the space station makes it past re-entry, then you wait some more. When you get down to 20,000ft or so jump out in parachutes. Land safely on the ground with the dog strapped to you back.

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Realistically the occupants of a space station wouldn't survive reentry let alone an uncontrolled descent toward the planet surface. As the station begins to de-orbit it accelerates and generates a lot of heat when coming in contact with the atmosphere and begins to burn up. It continues to accelerate and deteriorate due to forces that the station wasn't designed to withstand such as planetary gravitation, atmospheric pressure and temperature. The G forces would paste the human occupants into the bulkheads. Impact with the planet surface would destroy any evidence of the space station or its occupants. This is of course that the re-entry angle of descent was just right otherwise the station would bounce off the atmosphere and float around for all eternity with the astronauts still alive until they run out of food and water. Realistically speaking.

However if the space station were to have things like a substantial heat shielding, retro rockets, deflector shields and precise navigation ability and competent crew.. It could be doable.... Let's boldly go where no one has gone before..

As for good fiction it has been done.....KAHN!!!!!!!!!!....USS Botany Bay LLAP

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If the station is structurally able to withstand not burning up, and not breaking apart, which I think are unlikely for a space station, then the stresses on the astronauts is potentially survivable. One serious problem would be maintaining flight stability, as any sudden twists or rolls or flips could expose the crew to very high g forces, mushing them into the walls. However, you did mention anti-grav, and attitude control jets, and if these were able to compensate for the airflows over the station, then it might be a bumpy but survivable ride.

The station would decelerate constantly as it comes down, and final impact with the ground wouldn't be more than a few hundred kilometers an hour. This would not be survivable, but if your crew had access to parachutes, then an emergency bailout just before impact would give them good survival chances. This was a design feature for early Vostok missions, and even the Shuttle had crew egress and parachuting as a contingency plan for situations where landing might not work (losing pressure in the main tires prior to landing).

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