To safely explore the solar system and beyond, spaceships need to go faster—nuclear-powered rockets may be the answer

Jun 14, 2020
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As long as there is a fear of a rocket launch that has any risk of radioactive debris falling on the ground, no one will stand for nuclear rockets.
 
Jun 1, 2020
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It would seem more likely that some sort of fusion system would be the far better idea. Several kilograms of hydrogen could be scooped from the space travelled to minimize their hull impact and be used as fuel. Some of the helium produced could be used for the children's balloons as well. :)
 
Feb 14, 2020
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Response to Comment 1
If we design aerodynamic shape of reentry of Nuclear Power reactor then less chance that it would break as Radioisotope Thermal Generator on Apollo 13 Lunar module did enter safely and fell in Mariana Trench off east of Japan or south.
 
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Feb 14, 2020
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Response to Comment 2
Yes excellent idea, we have toget them working on earth then space.
If our congress had not adhoc terminated Tokomac and other related Fusion research 50 years ago, we would be in great shape today and not lose as we are losing in lot of other important areas where we have leadership.
 
May 4, 2020
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A desirable feature of nuclear reactors is that they are not radioactive until you start the chain reaction by turning them on. A launch accident wouldn't spread radioactive debris, because the reactor would be launched cold.
 
Feb 14, 2020
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Today we have better options

  • Wait for fusion to mature for rocket engines
  • Robotic assembly of fission reactor and making it critical remotely in space
  • Better shielding
  • Ion engine alternatives to chemical fuel
  • We had NERVA and other nuclear rocket programs at NASA during 1968-72 when I participated in Human Space Flight Program and also received NASA Apollo Achievement Award.
 
Jun 28, 2020
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Orion Project has been existed for quite sometime...

However, public fears of nuclear radioactive did halted it... which is, i think the biggest problem when it comes to anything to do with the word "Nuclear"/N-word

Heck even there is still to this days, people that fears of nuclear energy reactor...
 
Dec 11, 2019
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Thought this was interesting:

In the Sanskrit Samarangana Sutradhara (Literally, "controller of the battlefield"), it is written:


  • "Strong and durable must the body of the Vimana be made, like a great flying bird of light material. Inside one must put the mercury engine with its iron heating apparatus underneath. By means of the power latent in the mercury which sets the driving whirlwind in motion, a man sitting inside may travel a great distance in the sky. The movements of the Vimana are such that it can vertically ascend, vertically descend, move slanting forwards and backwards. With the help of the machines human beings can fly in the air and heavenly beings can come down to earth."
 
Oct 21, 2019
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Orion Project has been existed for quite sometime...

However, public fears of nuclear radioactive did halted it... which is, i think the biggest problem when it comes to anything to do with the word "Nuclear"/N-word

Heck even there is still to this days, people that fears of nuclear energy reactor...
Yeah but nobody is seriously suggesting using the Orion Project approach (letting off a series of miniature explosions against a "pusher plate" on the base of the vehicle to launch it from the ground through the atmosphere into Space), the resultant level of radioactive fallout would (rightly) prevent it being used. The Nuclear Thermal Propulsion approach being advocated would use a Uranium fuelled reactor which is only switched on once it has been been successfully launched by a conventional chemical rocket into Space.

And as regards the first comment on this thread from SDelMonte "As long as there is a fear of a rocket launch that has any risk of radioactive debris falling on the ground, no one will stand for nuclear rockets. " I don't know if the objectors realise that the Uranium fuel in a reactor which hasn't yet been switched on has negligible radioactivity (you can hold an unused Uranium fuel element safely in your hands), much less than that of the Plutonium 238 Radioisotope Thermal Generators on board numerous robotic spacecraft that have been safely launched and most people accept those. :)
 
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Jan 21, 2020
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Assuming the video clips of UFO declassified by Pentagon were real. Those clips have shed some light into the future of transport to mankind. The "Tic Tac" shaped transport vehicles were flying with instantaneous acceleration and deceleration. They could make 90 degree turn instantaneously. They could fly at a speed of 28,000 ft in 0.7 seconds, with neither hot spots nor emission detected. Their motions broke all Newton's law of motions. One speculation is, they are not governed by Gravity. Imagine a moving body that does not interact with Higgs Field. A moving body that does not have mass in the space it is travelling. If a vehicle can become "massless", it does not have to obey Newton's law, it can go at superluminal speed. Those 'Tic Tac' shaped transport vehicles has provided a glimpse into the far future of our technology, which we may or may never comprehend one day.
 
Feb 14, 2020
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Still fusion is preferred or the ion engines - safer
For nuclear thermal (Isotope generators) or electric power as in Apollo Lunar Expt Package (ALSEP) we generated power for lunar expts e.g. seismo-meters etc, for several years on Apollo flights.
I believe these types of generators were also carried on planetary satellite missions?
we need abundant non-solar power for outer planet missions.

Dr. Ravi Sharma
 
Jun 28, 2020
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the resultant level of radioactive fallout would (rightly) prevent it being used
No, im not a nuclear pyhsicst, but i've read paper about nuclear pulse rocket that did mention it's fallout could reduce close to safe levels by launch it from earth poles or design more effcient bombs that burnt most of its radioactive isotopes and so on....

So yeah, i still think that the public hysteric is unjustified....:rolleyes:
 
Oct 23, 2019
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I believe fusion is going to be the holy grail of space travel because reaction mass could be minimized; therefore reducing the mass of the entire spacecraft. If they can achieve a fusion engine that can deliver a constant acceleration of 1/3 g halfway to the target, say Mars for instance, then decelerate at 1/3 g for the remaining distance the trip would only take 60 days. Also the crew would spend minimal time in zero gravity. Accelerating for 1/3 g for 30 days would actually achieve a velocity of approximately 3% of the speed of light depending of the gain of relativistic mass. Laws of relativity suck though, so there is an upward limit of velocity due to the relativistic mass gained. I'll leave that for someone else to figure out as it would be dependent upon mass of the spacecraft, crew, rate of use of reaction mass and limit of available power.
 
Jul 2, 2020
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"such as hydrogen". Yes, certainly hydrogen. It has a lower atomic weight than any other propellant, so for a given temperature it gives the highest exhaust velocity. That's the only reason nuclear thermal gives a better specific impulse than chemical rockets. The relative energy density doesn't matter.
Nuclear electric gives an even better specific impulse, but requires a large radiator.
 
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Mar 19, 2020
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I believe fusion is going to be the holy grail of space travel because reaction mass could be minimized; therefore reducing the mass of the entire spacecraft.

Assuming cold fusion does not make a stunning recovery, how is a fusion rocket going to contain the multi-million K temperatures required from such a mechanism? I just don't see those break-even reactors outside Princeton etc. scaling up for spaceship propulsion.

The closest thing that comes to mind is the old concept of periodic detonation of "bombs" going off behind the space craft. But even that would be largely fission "propulsion" since those bombs, while called H-bombs in the press, are typically 90%+ fission.

It would seem a containment vessel would have some serious problems in shielding a fusion reactor by any technology made by humans. But I am certainly open to corrections.

Maybe we need to wait for more advances in particle physics. Perhaps propulsion by an antigraviton stream is just the ticket.
 
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Oct 23, 2019
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Assuming cold fusion does not make a stunning recovery, how is a fusion rocket going to contain the multi-million K temperatures required from such a mechanism? I just don't see those break-even reactors outside Princeton etc. scaling up for spaceship propulsion.
Fusion research is still in its infancy. I really don't see it happening in my lifetime or what's left of it. Inertial confinement or magnetic confinement right now seems to be the most promising, but will take years of development before it shows even a glimmer of scientific efficiency and years after that to achieve engineering efficiency. Do't much care for riding the shock wave of the H-bomb. I'll take nuclear-electric over that any day.
 
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Mar 19, 2020
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Fusion research is still in its infancy. I really don't see it happening in my lifetime or what's left of it. Inertial confinement or magnetic confinement right now seems to be the most promising, but will take years of development before it shows even a glimmer of scientific efficiency and years after that to achieve engineering efficiency. Don't much care for riding the shock wave of the H-bomb. I'll take nuclear-electric over that any day.
So, working with known physics and mechanics, let's assume we have a small enough fusion reactor, with confinement of a 15 million K plasma. You are getting a lot of power out a hydrogen feed into it. This in itself will not move a spaceship. Does the super hot product helium provide thrust? If so, how would that be conducted. These temperatures are way too high for anything, with the exception of confinement fields. Somehow, you must deal with the ultra-hot reactor product stream, and thrust seems a must, so to say.

Could "direct reactor product propulsion" be designed? It seems highly unlikely you could sustain such a mechanism. At least not in this century. It all seems to boil down to confinement technologies and power requirements. The more it is considered, the more it reminds me of Rube Goldberg's fabulous inventions........but perhaps not as fanciful. It certainly doesn't seem impossible with enough effort.

Short version : The power of fusion must somehow be converted into a mechanism of propulsion. This requires mass expulsion in the opposite direct you wish to move. And this might be a high temperature "ejecta" plasma for propulsion, but from what "fuel"? If not the product stream, something else?

Or do you resort to something more mechanical, like an "atomic electromagnetic rail-gun". perhaps throwing ionized atoms of some element down specialized "rails" at relativistic speeds. Not easy to see how you obtain a propulsion mechanism from fusion without throwing out mass in a major way to really get moving. Sacrificing parts of the ship as you go has unique benefits, especially for one-way trips!


 
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wikkid1show

Let's build a spaceship together
Apr 25, 2020
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I don't think so, my theory holds merit , let me explain it. Liek Myrabo gave us a lifting tool in which I understand how to incorporate more and make it subsequently the fastest ever . My list is extensive and all the technology is available as I write this . I just want help because I am an average Joe and don't have the income or the authority to gather the parts required. And furthermore like all the a list builders on the space program. I would go up on my first just because I know of its potential for the world and opening up an entire newly formed job description
 
Feb 14, 2020
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Assuming the video clips of UFO declassified by Pentagon were real. Those clips have shed some light into the future of transport to mankind. The "Tic Tac" shaped transport vehicles were flying with instantaneous acceleration and deceleration. They could make 90 degree turn instantaneously. They could fly at a speed of 28,000 ft in 0.7 seconds, with neither hot spots nor emission detected. Their motions broke all Newton's law of motions. One speculation is, they are not governed by Gravity. Imagine a moving body that does not interact with Higgs Field. A moving body that does not have mass in the space it is travelling. If a vehicle can become "massless", it does not have to obey Newton's law, it can go at superluminal speed. Those 'Tic Tac' shaped transport vehicles has provided a glimpse into the far future of our technology, which we may or may never comprehend one day.
the third clip with fan shaped structured occured and expanded many times on all human space flights whever gas or propellants (LH2, LO2 and H2O dumped in space and does not appear like UFO, it could be a rocket venting into space, just possibility to explore further.
 

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