Is it possible to re-enter the earths atmosphere without heating up?

[PaperclipGod]

I'm probably going to make myself look retarded (again), but after you finish laughing, kindly answer the question.

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So, I was just thinking about how hot the space shuttle gets when it re-enters the atmosphere. AFAIK, this is due to the shuttle slowing down as it hits the atmosphere, and that speed is dissipated in the form of drag/heat. I was wondering...

What if instead of trying to hurtle through the atmosphere at warp 9, a shuttle actually fired its rockets in the opposite direction (pretend it has gigantic gas tanks, too), and slowed its re-entry? And as it re-entered, it slowly adjusted the direction of its thrust to oppose the now predominantly "vertical" force of gravity. i.e., it'd be balancing on it's tail.

Mmm... yeah, so I guess this doesn't even remotely resemble the space shuttle anymore. But if such a vehicle existed -- is that kind of "cold" re-entry possible?

 

[MikeyIs4Dcats]

no, the friction of the atmosphere would still create heat

 

[PottedMeat]

hmm i don't see why not, besides as you said being incredibly wasteful.

 

[MJinZ]

Space = matterless.

Atmosphere = matter like Oxygen, Hydrogen, Nitrogen.

Matter moving against matter = Friction

Friction converts kinetic energy to thermal energy = Heat.

 

[Mr. Pedantic]

It's physically impossible to stop something heating up when they move. The act of typing this post out is creating heat from fluid resistance. So no, there is no way you could possibly stop the space shuttle from heating up on re-entry.

And the heat is not produced by it slowing down, it's produced by it speeding up everything else.

What if instead of trying to hurtle through the atmosphere at warp 9, a shuttle actually fired its rockets in the opposite direction (pretend it has gigantic gas tanks, too), and slowed its re-entry? And as it re-entered, it slowly adjusted the direction of its thrust to oppose the now predominantly "vertical" force of gravity. i.e., it'd be balancing on it's tail.

I'm not sure why you'd want to waste all that fuel when re-entry for the space shuttle is essentially free. And on a practical note, balancing the thing so it doesn't flip over, as you allude to, would be pretty hard.

 

[PaperclipGod]

Yeah, I realize this is all pointless and impractical -- that's not the point.

And when I was talking about avoiding heat, I wasn't including ALL heat, like the miniscule amount of heat dissipated via my fingers punching keys. I'm talking about levels of heat relative to the extremes that the space shuttle has to deal with on re-entry, which is something like 3k fahrenheit.

 

[JulesMaximus]

The Space Shuttle has to travel at 17,500mph just to maintain orbit around our planet, slow it to zero mph and it would fall to the earth like a rock and burn up/kill everyone on impact. Remove the heat shielding and it would burn up like a sheet of newspaper in a blast furnace. It couldn't hold enough fuel to slow its decent to a level that would allow reentry with no heat/friction...so your idea is completely ridiculous.

 

[PaperclipGod]

No, the shuttle is traveling way too fast in its orbit to enter the atmosphere without generating a crap ton of heat. Slow it to zero mph and it would fall to the earth like a rock and burn up/kill everyone on impact. It couldn't hold enough fuel to slow its decent to a level that would allow reentry with no heat/friction...so your idea is completely ridiculous.

I don't spend enough time here to recall if you're a troll, or if you just don't read posts before replying.

 

[KillerCharlie]

The Space Shuttle has to travel at 17,500mph just to maintain orbit around our planet, slow it to zero mph and it would fall to the earth like a rock and burn up/kill everyone on impact. Remove the heat shielding and it would burn up like a sheet of newspaper in a blast furnace. It couldn't hold enough fuel to slow its decent to a level that would allow reentry with no heat/friction...so your idea is completely ridiculous.

Not only would you need probably as much fuel as you did to get to orbit in the first place, you'd need more fuel to support the weight of that fuel.

 

[JulesMaximus]

I don't spend enough time here to recall if you're a troll, or if you just don't read posts before replying.

I post to piss you off. Did I achieve reentry? Dickwad?

 

[YOyoYOhowsDAjello]

Yeah, I bet you could design a vehicle to do it.

Pilots have ejected from an SR-71 at 80,000 feet traveling at mach 3 and made it to the ground safely on their own, so I don't think it would be unreasonable to think we could design something that would make the landing even smoother

Big waste of fuel to slow down quickly, but then parachutes could take care of the rest of it once there was enough atmosphere to take over.

 

[PaperclipGod]

I post to piss you off. Did I achieve reentry? Dickwad?

Reentry failed. Your old, rusty hulk burnt up somewhere over Siberia.

 

[PaperclipGod]

Yeah, I bet you could design a vehicle to do it.

Pilots have ejected from an SR-71 at 80,000 feet traveling at mach 3 and made it to the ground safely on their own, so I don't think it would be unreasonable to think we could design something that would make the landing even smoother

Big waste of fuel to slow down quickly, but then parachutes could take care of the rest of it once there was enough atmosphere to take over.

 

[Tiamat]

No, gravity pulls the shuttle fast enough where the friction between the sudden increase in mass contacting the shuttle surface (gaseous molecules etc.) will heat it up.

If the shuttle had an unlimited supply of fuel, it might be able to use engines pointing towards the surface to slow its decent such that it "minimally" heats due to friction, but that is generally regarded as unfeasible due to the massive amounts of fuel required.

 

[zinfamous]

I believe the answer is: no.

 

[zinfamous]

That guy has larger stones than Zeus.

such a badass.

 

[YOyoYOhowsDAjello]

I mentioned the SR-71 because the guys were still going at mach 3 when they ejected. With a freefall from the edge of space in a balloon, you don't have to deal with the re-entry speed issue (which I believe is the main problem you'd have to contend with)

 

[DrPizza]

Just for accuracy, it isn't friction that creates the heat in front of the shuttle. It's the adiabatic compression of the atmosphere in front of it.

 

[MagnusTheBrewer]

The answer to your question is yes IF, you had unlimited fuel.

 

[Red Squirrel]

Anti gravity is the answer. You need tons of power for that though. Over 9000 jigawatts!

 

[JulesMaximus]

I mentioned the SR-71 because the guys were still going at mach 3 when they ejected. With a freefall from the edge of space in a balloon, you don't have to deal with the re-entry speed issue (which I believe is the main problem you'd have to contend with)

I believe surface area, mass, and speed are the main problems you'd have to contend with.

 

[YOyoYOhowsDAjello]

I believe surface area, mass, and speed are the main problems you'd have to contend with.

If you started with 0 speed relative to the ground, would surface area and mass still be a problem? I wouldn't think those would be hard to deal with once the speed was controlled.

 

[ElFenix]

read up on spaceshipone (though it wouldn't work for orbital craft)

 

[JulesMaximus]

If you started with 0 speed relative to the ground, would surface area and mass still be a problem? I wouldn't think those would be hard to deal with once the speed was controlled.

No, the speed at which you would descend would be the problem and since you cannot control that without massive amounts of fuel for propulsion it's kind of a moot point.

 

[Rubycon]

Not so distant future:

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