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Posted: 9/16/2010 3:23:31 AM EDT
[#1]
There is no air in space so friction is a non issue, as far as running into space rocks I would avoid that. YMMV
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Posted: 9/16/2010 3:25:40 AM EDT
[#2]
The supernova's radiation would fry you long before heat became an issue.
OP if you're interested in space radiation at all, look up pulsars. |
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Posted: 9/16/2010 3:27:59 AM EDT
[#3]
Quoted:
There is no air in space so friction is a non issue, as far as running into space rocks I would avoid that. YMMV Not exactly true. It's just that the density of the gas is extremely low. There would be friction, but I have no idea how much of a problem it would be. Interstellar space has ~1 molecule per cm^3. |
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Posted: 9/16/2010 3:30:07 AM EDT
[#4]
I don't think that friction is why aircraft/spacecraft heat up. It's the compression of gases.
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Posted: 9/16/2010 3:36:29 AM EDT
[#5]
Nothing. The shields would protect the ship.
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Posted: 9/16/2010 3:46:49 AM EDT
[#6]
Quoted:
I don't think that friction is why aircraft/spacecraft heat up. It's the compression of gases. 
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Posted: 9/16/2010 3:47:39 AM EDT
[#7]
Quoted:
Nothing. The shields would protect the ship. captain kirk would know. |
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Posted: 9/16/2010 3:51:19 AM EDT
[#8]
Quoted: SR-71 travels 2,000 mph and frictional heating requires titanium skin. I was looking at this morning's APOD picture of the Veil Nebula, and calculated that the supernova remnants that make it up are traveling around 4,700,000 mph. What would happen to a spaceship that ran into that stuff at that speed? That is less than one percent c. Insignificant as a heating issue with the low densities and low masses of what makes up a nebula. |
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Posted: 9/16/2010 3:56:05 AM EDT
[#9]
The Veil nebula is 70 light-years across, and is made up of much of the oxygen, iron, helium, etc. from the original star. So there is a decent amount of matter there that's traveling at 4.7 million mph. I guess it's a question of density. Is there enough matter there to cause significant frictional heating if you hit at that relative velocity? I don't think the radiation from the pulsar would be a problem at 70 light-years, but maybe it would. I know a direct GRB from 3,000 light-years would pretty much fry our atmosphere, but a GRB is many orders of magnitude stronger than a pulsar. http://antwrp.gsfc.nasa.gov/apod/astropix.html  |
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Posted: 9/16/2010 4:07:33 AM EDT
[#10]
Quoted: Quoted: I don't think that friction is why aircraft/spacecraft heat up. It's the compression of gases. I'll quote you for LULZ when you educate yourself. |
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Posted: 9/16/2010 4:13:59 AM EDT
[#11]
Quoted:
Quoted:
SR-71 travels 2,000 mph and frictional heating requires titanium skin. I was looking at this morning's APOD picture of the Veil Nebula, and calculated that the supernova remnants that make it up are traveling around 4,700,000 mph. What would happen to a spaceship that ran into that stuff at that speed? That is less than one percent c. Insignificant as a heating issue with the low densities and low masses of what makes up a nebula. Even at that low speed, a whole percent of C is a lot of speed... the problem wouldn't be one of friction but of the fact that hydrogen would behave like cosmic radiation... ...or not... |
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Posted: 9/16/2010 4:14:56 AM EDT
[#12]
Quoted: Quoted: Quoted: SR-71 travels 2,000 mph and frictional heating requires titanium skin. I was looking at this morning's APOD picture of the Veil Nebula, and calculated that the supernova remnants that make it up are traveling around 4,700,000 mph. What would happen to a spaceship that ran into that stuff at that speed? That is less than one percent c. Insignificant as a heating issue with the low densities and low masses of what makes up a nebula. Even at that low speed, a whole percent of C is a lot of speed... the problem wouldn't be one of friction but of the fact that hydrogen would behave like cosmic radiation... Esplain, please? Are you talking about alpha? |
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Posted: 9/16/2010 4:23:11 AM EDT
[#13]
Quoted: Quoted: Quoted: SR-71 travels 2,000 mph and frictional heating requires titanium skin. I was looking at this morning's APOD picture of the Veil Nebula, and calculated that the supernova remnants that make it up are traveling around 4,700,000 mph. What would happen to a spaceship that ran into that stuff at that speed? That is less than one percent c. Insignificant as a heating issue with the low densities and low masses of what makes up a nebula. Even at that low speed, a whole percent of C is a lot of speed... the problem wouldn't be one of friction but of the fact that hydrogen would behave like cosmic radiation... ...or not... It is kind of a strange question. Any interstellar ship would be moving at a useful speed, not standing still to get pelted. That useful speed would be a significant fraction of c and would make the .007c of the expanding gas to be insignificant. |
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Posted: 9/16/2010 4:32:41 AM EDT
[#14]
Quoted:
Quoted:
Quoted:
Quoted:
SR-71 travels 2,000 mph and frictional heating requires titanium skin. I was looking at this morning's APOD picture of the Veil Nebula, and calculated that the supernova remnants that make it up are traveling around 4,700,000 mph. What would happen to a spaceship that ran into that stuff at that speed? That is less than one percent c. Insignificant as a heating issue with the low densities and low masses of what makes up a nebula. Even at that low speed, a whole percent of C is a lot of speed... the problem wouldn't be one of friction but of the fact that hydrogen would behave like cosmic radiation... Esplain, please? Are you talking about alpha? Read more science fiction, specifically Larry Niven. |
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Posted: 9/16/2010 4:34:04 AM EDT
[#15]
Quoted: Quoted: Quoted: Quoted: Quoted: SR-71 travels 2,000 mph and frictional heating requires titanium skin. I was looking at this morning's APOD picture of the Veil Nebula, and calculated that the supernova remnants that make it up are traveling around 4,700,000 mph. What would happen to a spaceship that ran into that stuff at that speed? That is less than one percent c. Insignificant as a heating issue with the low densities and low masses of what makes up a nebula. Even at that low speed, a whole percent of C is a lot of speed... the problem wouldn't be one of friction but of the fact that hydrogen would behave like cosmic radiation... Esplain, please? Are you talking about alpha? Read more science fiction, specifically Larry Niven. No Cliff Notes for me? Oh well... |
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Posted: 9/16/2010 4:34:17 AM EDT
[#16]
Quoted: Quoted: I don't think that friction is why aircraft/spacecraft heat up. It's the compression of gases. Don't you know how magnets work? |
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Posted: 9/16/2010 4:35:18 AM EDT
[#17]
Quoted:
Quoted:
There is no air in space so friction is a non issue, as far as running into space rocks I would avoid that. YMMV Not exactly true. It's just that the density of the gas is extremely low. There would be friction, but I have no idea how much of a problem it would be. Interstellar space has ~1 molecule per cm^3. Some sort of electronic field that would block (or if you new what the particle charge was) / repel gaseous particles would be the answer. |
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Posted: 9/16/2010 4:36:52 AM EDT
[#18]
Quoted: The Veil nebula is 70 light-years across, and is made up of much of the oxygen, iron, helium, etc. from the original star. So there is a decent amount of matter there that's traveling at 4.7 million mph. I guess it's a question of density. Is there enough matter there to cause significant frictional heating if you hit at that relative velocity? I don't think the radiation from the pulsar would be a problem at 70 light-years, but maybe it would. I know a direct GRB from 3,000 light-years would pretty much fry our atmosphere, but a GRB is many orders of magnitude stronger than a pulsar. http://antwrp.gsfc.nasa.gov/apod/astropix.html http://antwrp.gsfc.nasa.gov/apod/image/1009/Veil_pugh_900c.jpg Oops my mistake, I thought you were asking what would happen if a spacecraft were to enter a newly formed nova event. From what I understand, the particulate matter in such an event as the one you've described above would be so disperse as to not cause a friction issue. Now, micrometeorites, debris and (back to radiation) would be an issue, especially as nova events tend to fling out all sorts of gunk in a big damn hurry. It's almost like dropping a rock in a pond and watching the ripples form, but at a 360deg plane rather than 90. |
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Posted: 9/16/2010 4:40:48 AM EDT
[#19]
Quoted: Quoted: The Veil nebula is 70 light-years across, and is made up of much of the oxygen, iron, helium, etc. from the original star. So there is a decent amount of matter there that's traveling at 4.7 million mph. I guess it's a question of density. Is there enough matter there to cause significant frictional heating if you hit at that relative velocity? I don't think the radiation from the pulsar would be a problem at 70 light-years, but maybe it would. I know a direct GRB from 3,000 light-years would pretty much fry our atmosphere, but a GRB is many orders of magnitude stronger than a pulsar. http://antwrp.gsfc.nasa.gov/apod/astropix.html http://antwrp.gsfc.nasa.gov/apod/image/1009/Veil_pugh_900c.jpg Oops my mistake, I thought you were asking what would happen if a spacecraft were to enter a newly formed nova event. From what I understand, the particulate matter in such an event as the one you've described above would be so disperse as to not cause a friction issue. Now, micrometeorites, debris and (back to radiation) would be an issue, especially as nova events tend to fling out all sorts of gunk in a big damn hurry. It's almost like dropping a rock in a pond and watching the ripples form, but at a 360deg plane rather than 90. I would think that the energy release from a supernova would instantly turn everything in its solar system into their atoms and plasma. No rocky material (or even dust) would remain. After all, a supernova outshines an entire galaxy when it goes off. And I don't think there's any rocky debris in intersteller space. |
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Posted: 9/16/2010 4:44:26 AM EDT
[#20]
Quoted: The close material sure, but if there's nothing substantial to slow the energy wave down, it'll shove surrounding meteors/planets/comets/gasses and material around violently. Quoted: Quoted: The Veil nebula is 70 light-years across, and is made up of much of the oxygen, iron, helium, etc. from the original star. So there is a decent amount of matter there that's traveling at 4.7 million mph. I guess it's a question of density. Is there enough matter there to cause significant frictional heating if you hit at that relative velocity? I don't think the radiation from the pulsar would be a problem at 70 light-years, but maybe it would. I know a direct GRB from 3,000 light-years would pretty much fry our atmosphere, but a GRB is many orders of magnitude stronger than a pulsar. http://antwrp.gsfc.nasa.gov/apod/astropix.html http://antwrp.gsfc.nasa.gov/apod/image/1009/Veil_pugh_900c.jpg Oops my mistake, I thought you were asking what would happen if a spacecraft were to enter a newly formed nova event. From what I understand, the particulate matter in such an event as the one you've described above would be so disperse as to not cause a friction issue. Now, micrometeorites, debris and (back to radiation) would be an issue, especially as nova events tend to fling out all sorts of gunk in a big damn hurry. It's almost like dropping a rock in a pond and watching the ripples form, but at a 360deg plane rather than 90. I would think that the energy release from a supernova would instantly turn everything in its solar system into their atoms and plasma. No rocky material (or even dust) would remain. After all, a supernova outshines an entire galaxy when it goes off. And I don't think there's any rocky debris in intersteller space. |
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Posted: 9/16/2010 4:50:02 AM EDT
[#21]
Quoted: Quoted: The close material sure, but if there's nothing substantial to slow the energy wave down, it'll shove surrounding meteors/planets/comets/gasses and material around violently. Quoted: Quoted: The Veil nebula is 70 light-years across, and is made up of much of the oxygen, iron, helium, etc. from the original star. So there is a decent amount of matter there that's traveling at 4.7 million mph. I guess it's a question of density. Is there enough matter there to cause significant frictional heating if you hit at that relative velocity? I don't think the radiation from the pulsar would be a problem at 70 light-years, but maybe it would. I know a direct GRB from 3,000 light-years would pretty much fry our atmosphere, but a GRB is many orders of magnitude stronger than a pulsar. http://antwrp.gsfc.nasa.gov/apod/astropix.html http://antwrp.gsfc.nasa.gov/apod/image/1009/Veil_pugh_900c.jpg Oops my mistake, I thought you were asking what would happen if a spacecraft were to enter a newly formed nova event. From what I understand, the particulate matter in such an event as the one you've described above would be so disperse as to not cause a friction issue. Now, micrometeorites, debris and (back to radiation) would be an issue, especially as nova events tend to fling out all sorts of gunk in a big damn hurry. It's almost like dropping a rock in a pond and watching the ripples form, but at a 360deg plane rather than 90. I would think that the energy release from a supernova would instantly turn everything in its solar system into their atoms and plasma. No rocky material (or even dust) would remain. After all, a supernova outshines an entire galaxy when it goes off. And I don't think there's any rocky debris in intersteller space. I wonder. Is enough energy released to instantly 'de-construct' (can't come up with the right word...vaporize? annihilate?) all the material in the local system? I'll have to look that up. |
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Posted: 9/16/2010 7:27:33 AM EDT
[#22]
Quoted: Quoted: Quoted: The close material sure, but if there's nothing substantial to slow the energy wave down, it'll shove surrounding meteors/planets/comets/gasses and material around violently. Quoted: Quoted: The Veil nebula is 70 light-years across, and is made up of much of the oxygen, iron, helium, etc. from the original star. So there is a decent amount of matter there that's traveling at 4.7 million mph. I guess it's a question of density. Is there enough matter there to cause significant frictional heating if you hit at that relative velocity? I don't think the radiation from the pulsar would be a problem at 70 light-years, but maybe it would. I know a direct GRB from 3,000 light-years would pretty much fry our atmosphere, but a GRB is many orders of magnitude stronger than a pulsar. http://antwrp.gsfc.nasa.gov/apod/astropix.html http://antwrp.gsfc.nasa.gov/apod/image/1009/Veil_pugh_900c.jpg Oops my mistake, I thought you were asking what would happen if a spacecraft were to enter a newly formed nova event. From what I understand, the particulate matter in such an event as the one you've described above would be so disperse as to not cause a friction issue. Now, micrometeorites, debris and (back to radiation) would be an issue, especially as nova events tend to fling out all sorts of gunk in a big damn hurry. It's almost like dropping a rock in a pond and watching the ripples form, but at a 360deg plane rather than 90. I would think that the energy release from a supernova would instantly turn everything in its solar system into their atoms and plasma. No rocky material (or even dust) would remain. After all, a supernova outshines an entire galaxy when it goes off. And I don't think there's any rocky debris in intersteller space. I wonder. Is enough energy released to instantly 'de-construct' (can't come up with the right word...vaporize? annihilate?) all the material in the local system? I'll have to look that up. Atomize and yes, absolutely. |
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Posted: 9/16/2010 7:53:49 AM EDT
[#23]
At low, low speeds particle interaction is low due to the density in space, but once you start speeding up, it starts to become an issue.
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Posted: 9/16/2010 9:00:24 AM EDT
[#24]
Quoted: Quoted: Nothing. The shields would protect the ship. captain kirk would know. Deflector shields FTW.  |
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Posted: 9/16/2010 9:02:28 AM EDT
[#25]
Quoted:
Quoted:
Quoted:
Nothing. The shields would protect the ship. captain kirk would know. Deflector shields FTW. http://img.photobucket.com/albums/v374/qwertyup/Star%20Trek/1701a-2.gif Plus if you don't have them what are you going to reverse to produce an inverse tachyon beam? |
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Posted: 9/16/2010 9:05:23 AM EDT
[#26]
E=1/2mv^2
do the math yourself |
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Posted: 9/16/2010 9:18:18 AM EDT
[#27]
Avoiding the original question, supernovas are where the material that forms planets comes from.
The Hydrogen fluoresces beautifully in time-lapse photos, but the silicon and carbon particles will sand blast you far more. |
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Posted: 9/16/2010 9:21:13 AM EDT
[#28]
friction isn't an issue in space, as long as there is no space dust or anything like that.
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Posted: 9/16/2010 9:21:14 AM EDT
[#29]
Its not the friction but that little speck of space dust that will ruin your day
Shields will be needed Or jump ship type moves |
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Posted: 9/16/2010 9:31:23 AM EDT
[#30]
E.E. "Doc" Smith used interstellar matter as way to determine the top speed of his Lensman series ships which flew inertialess ... so it wasn't really the same as friction at all, the impact of a single atom with inertia would effect an inertialess object that did not have thrusters ... yeah, sorry I typed all this but since I did you're stuck with it.
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Posted: 9/16/2010 10:05:36 AM EDT
[#31]
This is an interesting question. Sure, there are fewer particles to create friction heating, compared to Earth atmosphere. But an interstellar ship is also travelling a long way, giving heat more time to build up.
One of the major difficulties in satellite design is figuring a way to get rid of excess heat, since there is no air to carry away that heat. Surprising, since space is generally considered to be at absolute zero; but you have to have some way to conduct the heat away, because heat radiation is pretty slow. |
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Posted: 9/16/2010 10:13:20 AM EDT
[#32]
Quoted:
Quoted:
There is no air in space so friction is a non issue, as far as running into space rocks I would avoid that. YMMV Not exactly true. It's just that the density of the gas is extremely low. There would be friction, but I have no idea how much of a problem it would be. Interstellar space has ~1 molecule per cm^3. Now figure you're moving at a large fraction of the speed of light, say 1*10^10 cm/s. Now, you've suddenly got 10 billion collisions per cm squared every second, all at extremely high velocity. ETA: It's been awhile since I did the calculation, but IIRC that is actually a larger rate of collisions than atmospheric pressure/temperature cause, and at a much, much higher velocity. ETAA: Nope, atmospheric temp/pressure nets about 10^23 collisions/cm^2*s. Still, that v^2 term in the kinetic energy equation will be a bitch. |
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Posted: 9/16/2010 11:05:43 AM EDT
[#33]
Quoted: Quoted: Quoted: There is no air in space so friction is a non issue, as far as running into space rocks I would avoid that. YMMV Not exactly true. It's just that the density of the gas is extremely low. There would be friction, but I have no idea how much of a problem it would be. Interstellar space has ~1 molecule per cm^3. Now figure you're moving at a large fraction of the speed of light, say 1*10^10 cm/s. Now, you've suddenly got 10 billion collisions per cm squared every second, all at extremely high velocity. ETA: It's been awhile since I did the calculation, but IIRC that is actually a larger rate of collisions than atmospheric pressure/temperature cause, and at a much, much higher velocity. ETAA: Nope, atmospheric temp/pressure nets about 10^23 collisions/cm^2*s. Still, that v^2 term in the kinetic energy equation will be a bitch. Alright, say you're moving along at a significant fraction of c and you hit the nebula. What happens is the vast magnetic fields funneling hydrogen into your fusion reactor (and at the same time protecting your hull) get overwhelmed. The particles eat away at your forward hull enough to damage the structure of your reverse fusion engine. Now you can't slow down. Moving that fast means you can't just flip a bitch and stand on your tail to slow down either - a few moments sideways in space with no shielding and ambient gas and particles impacting your hull like so many antimatter annihilation explosions will tear your ship apart. Your only option is to keep accelerating, and seek an area of space with a low enough gas concentration to make repairs. If you can't find it, you're doomed to keep accelerating, and might have to ride out the Big Crunch. |
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Posted: 9/16/2010 11:25:10 AM EDT
[#34]
plus even if there was friction the temperature in space is very low and would cool everything down to perfect operating temp..... now back to my room at the holiday in express
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Posted: 9/16/2010 11:30:27 AM EDT
[#35]
Quoted:
plus even if there was friction the temperature in space is very low and would cool everything down to perfect operating temp..... now back to my room at the holiday in express No, as already stated there isn't much in the way of conductive/convective cooling in space. Only radiative, which isn't very effective until you start to get really, really hot. Think of how a thermos works...the insulating "material" is actually a vacuum. |
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Posted: 9/16/2010 11:33:43 AM EDT
[#36]
Heat from friction isn't the issue; lack of ability to dispose heat is.
All internal equipment generate heat, and the problem isn't just heating the interior, it's disposing of waste heat since radiant cooling as would be done in a normal atmospheric environment can't be done. |
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Posted: 9/16/2010 11:34:02 AM EDT
[#37]
In interstellar space, at high fractions of the speed of light, friction is not an issue.
Radiation is. However, when you're going that fast, the random gas and dust molecules act more like cosmic rays than kinetic impactors. Although "bigger" but still almost microscopically small bits of interstellar dust (and yes, there is some out there...) start impacting with the force of several kiloton atomic bombs on up. Barring fanciful force field technology, one way to deal with it would be to make a huge slug of ice or asteroid rock, accelerate it with your ship, then release it so it drifted a light-day or so ahead of you and your ship rides in the path it clears for you. Then, when you get ready for braking/turnaround at the destination star-system, you just let the shield go, and your ship's mass-fraction is also much, much, better. And if it wasn't a one-way colonization mission, then what you do is mine the local resources of that star-system to make another shield slug, and repeat the process on the next voyage, or the return trip, whichever it was to be. Quoted:
Heat from friction isn't the issue; lack of ability to dispose heat is. All internal equipment generate heat, and the problem isn't just heating the interior, it's disposing of waste heat since radiant cooling as would be done in a normal atmospheric environment can't be done. Indeed. All realistic starship designs even near-term interplanetary spacecraft for use in our own Solar System include MASSIVE radiators to get rid of waste heat. In fact, if you look at the International Space Station, half the things that LOOK like solar panels are actually radiators. |
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Posted: 9/16/2010 11:39:44 AM EDT
[#38]
Interstellar ships have repulsers in the front and rear of the ship that use gravitrons to move any matter in the direction of travel out of the way and the ship moves into that space. Thus there is always an area of total vacuum in front of the ship.
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Posted: 9/16/2010 11:46:12 AM EDT
[#39]
Quoted: E=1/2mv^2 do the math yourself I have house elves to do that shit for me. |
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Posted: 9/16/2010 12:33:05 PM EDT
[#40]
Quoted:
Quoted:
Quoted:
I don't think that friction is why aircraft/spacecraft heat up. It's the compression of gases. I'll quote you for LULZ when you educate yourself. Care to elucidate my addled mind? How can compression of gas = heat without friction? My understanding is that the heat of re-entry or high atmospheric velocity is due to the friction of the gas molecules on the surface of the vessel. A wave compression in front of the vessel only compounds the problem given that the density of the gas molecules is higher in the compression wave which makes more friction. Heat from compression of a gas is from friction. If I'm wrong, show me how. I don't think I am though. |
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Posted: 9/16/2010 1:03:36 PM EDT
[#41]
Quoted: As something like the space shuttle travels through the atmosphere it is continually compressing the air in front of it. Compressing a gas causes the gas to heat which in turn heats the craft. For an easier seen example, the compressor on a refrigerator or air conditioner gets hot from compressing the coolant gas, no friction involved.Quoted: Quoted: Quoted: I don't think that friction is why aircraft/spacecraft heat up. It's the compression of gases. I'll quote you for LULZ when you educate yourself. Care to elucidate my addled mind? How can compression of gas = heat without friction? My understanding is that the heat of re-entry or high atmospheric velocity is due to the friction of the gas molecules on the surface of the vessel. A wave compression in front of the vessel only compounds the problem given that the density of the gas molecules is higher in the compression wave which makes more friction. Heat from compression of a gas is from friction. If I'm wrong, show me how. I don't think I am though. |
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Posted: 9/16/2010 6:43:23 PM EDT
[#42]
Quoted:
Quoted:
As something like the space shuttle travels through the atmosphere it is continually compressing the air in front of it. Compressing a gas causes the gas to heat which in turn heats the craft. For an easier seen example, the compressor on a refrigerator or air conditioner gets hot from compressing the coolant gas, no friction involved.
Quoted:
Quoted:
Quoted:
I don't think that friction is why aircraft/spacecraft heat up. It's the compression of gases. I'll quote you for LULZ when you educate yourself. Care to elucidate my addled mind? How can compression of gas = heat without friction? My understanding is that the heat of re-entry or high atmospheric velocity is due to the friction of the gas molecules on the surface of the vessel. A wave compression in front of the vessel only compounds the problem given that the density of the gas molecules is higher in the compression wave which makes more friction. Heat from compression of a gas is from friction. If I'm wrong, show me how. I don't think I am though. Edited: Nevermind. You're right. I hate it when what I was taught in school is wrong. |
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Posted: 9/16/2010 6:54:54 PM EDT
[#43]
Quoted: No, it's not. If that were the case, it would heat again upon pressure release, because there is friction then, too. But what happens to your hand when you drip liquid butane on it? It freezes as the liquid boils off, that's what. That is also how refrigeration works: The compressor compresses the gaseous refrigerant, which gives off heat (gets hot) in the condenser as it becomes liquid, then the pressure is dropped across an orifice and the refrigerant picks up heat (gets cold) as it boils.Quoted: Quoted: Quoted: I don't think that friction is why aircraft/spacecraft heat up. It's the compression of gases. I'll quote you for LULZ when you educate yourself. Care to elucidate my addled mind? How can compression of gas = heat without friction? My understanding is that the heat of re-entry or high atmospheric velocity is due to the friction of the gas molecules on the surface of the vessel. A wave compression in front of the vessel only compounds the problem given that the density of the gas molecules is higher in the compression wave which makes more friction. Heat from compression of a gas is from friction. If I'm wrong, show me how. I don't think I am though. |
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Posted: 9/16/2010 7:03:04 PM EDT
[#44]
Quoted:
The Veil nebula is 70 light-years across, and is made up of much of the oxygen, iron, helium, etc. from the original star. So there is a decent amount of matter there that's traveling at 4.7 million mph. I guess it's a question of density. Is there enough matter there to cause significant frictional heating if you hit at that relative velocity? I don't think the radiation from the pulsar would be a problem at 70 light-years, but maybe it would. I know a direct GRB from 3,000 light-years would pretty much fry our atmosphere, but a GRB is many orders of magnitude stronger than a pulsar. http://antwrp.gsfc.nasa.gov/apod/astropix.html http://antwrp.gsfc.nasa.gov/apod/image/1009/Veil_pugh_900c.jpg This is what causes all the turbulence (shakey stuff) on the Enterprise. |
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Posted: 9/16/2010 7:13:06 PM EDT
[#45]
Quoted:
Quoted:
Nothing. The shields would protect the ship. captain kirk would know. CPT Kirk would be too busy figuring out how to fuck it to solve the problem. |
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Posted: 9/16/2010 7:14:48 PM EDT
[#46]
Quoted:
In interstellar space, at high fractions of the speed of light, friction is not an issue. Radiation is. However, when you're going that fast, the random gas and dust molecules act more like cosmic rays than kinetic impactors. Although "bigger" but still almost microscopically small bits of interstellar dust (and yes, there is some out there...) start impacting with the force of several kiloton atomic bombs on up. Barring fanciful force field technology, one way to deal with it would be to make a huge slug of ice or asteroid rock, accelerate it with your ship, then release it so it drifted a light-day or so ahead of you and your ship rides in the path it clears for you. Then, when you get ready for braking/turnaround at the destination star-system, you just let the shield go, and your ship's mass-fraction is also much, much, better. And if it wasn't a one-way colonization mission, then what you do is mine the local resources of that star-system to make another shield slug, and repeat the process on the next voyage, or the return trip, whichever it was to be. Quoted:
Heat from friction isn't the issue; lack of ability to dispose heat is. All internal equipment generate heat, and the problem isn't just heating the interior, it's disposing of waste heat since radiant cooling as would be done in a normal atmospheric environment can't be done. Indeed. All realistic starship designs even near-term interplanetary spacecraft for use in our own Solar System include MASSIVE radiators to get rid of waste heat. In fact, if you look at the International Space Station, half the things that LOOK like solar panels are actually radiators. I was completely unaware of the lack of heat dissipation, and trying to wrap my brain around the concept, has cause small bits of it to leak out my ear. |
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Posted: 9/17/2010 2:33:21 PM EDT
[#47]
Quoted: Alright, say you're moving along at a significant fraction of c and you hit the nebula. What happens is the vast magnetic fields funneling hydrogen into your fusion reactor (and at the same time protecting your hull) get overwhelmed. The particles eat away at your forward hull enough to damage the structure of your reverse fusion engine. Now you can't slow down. Moving that fast means you can't just flip a bitch and stand on your tail to slow down either - a few moments sideways in space with no shielding and ambient gas and particles impacting your hull like so many antimatter annihilation explosions will tear your ship apart. Your only option is to keep accelerating, and seek an area of space with a low enough gas concentration to make repairs. If you can't find it, you're doomed to keep accelerating, and might have to ride out the Big Crunch. I don't know - that sounds really, really cool... |
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