Project Orion Revisited. - Why not an Earth Launch?

soph · 2002-12-11 21:27:08

nuclearspace, you speak of nuclear energy in only positive terms. i agree that nuclear power is a key part of our future in space; however, we must remember that radiation is dangerous. im not off hugging any trees or anything, but i do think that blowing up atomic weapons in our atmosphere is a bad idea. in outer space, sure, who are you hurting?

if there are alternatives that are safer, and nearly as effective, why not use them? just because it is not "the worst beast out there" doesnt mean that its perfectly ok. nuclear pulse propulsion i dont agree with, at least near earth. i support the use of fission, but with care. remember, when many of those tests were done, we had war fever, and the government did a lot of things that would be very controversial today. not to mention the higher than usual rate of cancer around atomic test sites.

like i said, theres nothing wrong with nuclear energy. but its not perfect, and we have to be careful with it.

Phobos · 2002-12-11 22:17:25

I agree with soph. Even though I used to support the idea of using Orions for ground launch the problems with fallout and emp blasts seem insurmountable. I think Orion type propulsion would be ok once your safely away from Earth but I'd be wary of using it for ground launches.

RobertDyck · 2002-12-12 01:07:58

Orion really has 2 problems: you are detonating a nuclear explosive right behind the spacecraft and you are exposing the crew to intense radiation.

I could agree with you about the minimized impact of radioactive fallout, if the launch was timed with weather so that fallout fell into the ocean. But the crew are within the blast zone of the explosion, otherwise it wouldn't produce thrust. US Army experiments with soldiers in trenches within the blast zone of a nuclear detonation produced extreme rates of cancer; and those soldiers had how many tons of dirt to shield them? Now add the mass of shielding to make that intensity of radiation safe for the crew, and how much mass do you have left for payload?

Now examine the fact that you are detonating a nuclear explosive. If any faults occur in the concussion plate the ship will literally blow itself up in a nuclear explosion. If any debris is chipped off the concussion plate, the next nuclear explosion will throw that debris into the ship with the force of a nuclear explosion.

Then you have to worry about detonating your fuel. Remember the fuel is a series of nuclear bombs. A small nuke is a fission bomb, shaped pieces of uranium or plutonium with chemical explosives shaped to crush the fissile material into critical mass quickly. Could concussive shock detonate the chemical explosive? If all the chemical explosive of one small bomb detonated at once, that would detonate the nuclear explosion. If the chemical explosive detonated asymmetrically that would not detonate the nuke, but it would still be a significant chemical explosive and it could detonate the chemical explosive of all the bombs in the magazine. That could destroy the ship. You could argue that the fuel tank of a chemical rocket could also explode, but a chemical rocket does not have explosions going off just feet away from its fuel tank.

Now don't get me wrong. Don't call me anti-nuclear. I still think a Nuclear Thermal Rocket is a great idea, and we could have gotten to Mars in the late 1970s if we continued with Nerva. Call me a strong advocate of NTR. Today we have a few choices. Timberwind is a NTR with Isp of 1000 seconds in vacuum and Timberwind 250 has a thrust of 250,000kgf (kilogram force). The Timberwind launch vehicle was designed by DARPA in 1992 to launch from the surface with 2 Titan solid rocket boosters. The other choice is Nuclear Electric Propulsion. Electric thrusters with Isp in the 8000-9000 second range are in development now. If specific impulse is the goal, NEP is the most efficient.

TJohn · 2002-12-12 08:15:16

How large would Orion be? What is the estimated crew size? Does it have steerable engines? I have heard of Orion before since that was our closest nuclear propulsion spaceship. It's a shame when it died.

People will always complain about fallout and radiation. Well, standing next to a microwave gives you radiation. If launching from the ocean proves to the scientists, and more importantly the general public, that a 0.1 KT detonation is harmless to propel a ship into space, then IT SHOULD HAPPEN! How else are we going to test applications without testing first? Computer programs can only do so much.

soph · 2002-12-12 14:11:32

we have enough information on all variables that computer simulations can tell us enough to sway the issue one way or another.

soph · 2002-12-12 21:50:26

i still dont like the idea of exploding nuclear bombs in earth atmosphere. is there any way to get the ship into space before using the bombs?

maybe the pulses could be combined with another type of nuclear power, where the pulses could be used to provide short periods of high acceleration. but you seem to be the expert on the issue, nuclearspace. could this work?

soph · 2002-12-12 22:03:42

well, let me ask this: is there any method of propulsion available in the near future that could provide the same benefits as nuclear pulse propulsion, but with less safety risk (at least, less psychological risk...to be honest, im still not sold on blowing up hydrogen bombs in the atmosphere ??? )?

Phobos · 2002-12-12 22:44:26

It would be hard to beat an orion type ship for sheer lifting ability and power. Mauk2's concept of a gas core nuke rocket seemed like an interesting alternative even though I have to admit that I'm still sold on the idea of building giant space elevators. It would take longer to put big payloads into space but they would still get there and cheaper nonetheless. There are chemical rockets like the Sea Dragon that are designed to be cheap and could lift 500 tons into LEO. A far cry from the thousands of tons of cargo an orion could theoretically carry but still no small amount to sneeze at.

Shaun Barrett · 2002-12-13 02:53:59

If Soph's attitude were typical of most people, then the political obstacles to Orion would be insurmountable.
It seems there's an entirely visceral response that automatically arises in some people when nuclear explosions in the atmosphere are mentioned - perhaps understandably because of 'little boy' and 'fat man' in 1945.

What's worrying for any serious attempt at resurrecting Orion is that it might prove impossible to overcome this irrational fear of nuclear power used in this way. Even though NuclearSpace went to great lengths to emphasise the condition that careful testing would be a prerequisite, that extremely 'clean' devices might be developed, that atmospheric pollution would be extrtemely limited and very short-lived, still Soph remains nervous!! And Soph, just by being part of these forums, has shown he (? ) is probably more likely to be of a scientific mindset than the average person!
If the average person is going to simply close his or her mind the minute someone says "nuclear-pulse inside the atmosphere", without ever examining the facts, then Orion has no hope at all of ever getting off the drawing-board!

If a completely safe Orion could be built, it would be a major boon for space exploration. It's such a pity to think that an irrational fear born of ignorance could kill it stone dead before it even starts!

AltToWar · 2002-12-13 05:28:56

If Soph's attitude were typical of most people, then the political obstacles to Orion would be insurmountable.
It seems there's an entirely visceral response that automatically arises in some people when nuclear explosions in the atmosphere are mentioned - perhaps understandably because of 'little boy' and 'fat man' in 1945.
What's worrying for any serious attempt at resurrecting Orion is that it might prove impossible to overcome this irrational fear of nuclear power used in this way. Even though NuclearSpace went to great lengths to emphasise the condition that careful testing would be a prerequisite, that extremely 'clean' devices might be developed, that atmospheric pollution would be extrtemely limited and very short-lived, still Soph remains nervous!! And Soph, just by being part of these forums, has shown he (? ) is probably more likely to be of a scientific mindset than the average person!
If the average person is going to simply close his or her mind the minute someone says "nuclear-pulse inside the atmosphere", without ever examining the facts, then Orion has no hope at all of ever getting off the drawing-board!
If a completely safe Orion could be built, it would be a major boon for space exploration. It's such a pity to think that an irrational fear born of ignorance could kill it stone dead before it even starts!

Are you sure it is irrational fear?

How many times have we been told by the scientific community that somthing it totally safe, ony to find a few decades later that a statistic increase of Ailment X is in direct proportion to exposure to Safe-Science-Y.

In this day and age, anyone can buy a 'scientific study' that can prove safe anything.

Scientists have proven that smoking is safe. Scientitsts have proven Depleated Uranium is safe. Scientists have proven that Small doses of mercury are ok to put in infant vaccines. Scientists have shown that global warming is nothing to worry about.

How can the public trust the scientific community when it can so easily be bought?

TJohn · 2002-12-13 07:22:22

I agree Shaun. People are more aware of things scientific than they were 40-50 yrs ago but still have that 1950s mind set of anything nuclear or "atomic" is bad. I've said it before and I'll say it again. With the current administration and a majority Republican House and Senate, there needs to be a push on the nuclear movement!

Just imagine having a crew exploring our solar system within our lifetimes. It's only going to happen with nuclear propulsion.

soph · 2002-12-13 07:57:36

i dont fear everything nuclear, thats totally off base. but blowing up hydrogen bombs in earths atmosphere is another story. nuclear energy is the future of space exploration--but not every nuclear energy source is as risky as nuclear weapons.

i support nuclear power. but there are two sides to everything. you should know that shaun. just because one person has provided numbers to prove a point, doesnt mean somebody else couldnt provide numbers that show that the opposite is true.

Phobos · 2002-12-13 13:48:13

Soph seems open to the possibilities of nuclear power but I share his cautious outlook on using orions for ground launches. If we could build nukes that could explode without producing any fallout that would solve a lot of the environmental problems but I still worry about things like emp pulses.

Shaun Barrett · 2002-12-13 20:07:39

I fear AltToWar may suffer from terminal paranoia. It appears everything is bad in his book: Right-wing governments are out to enslave us and now the scientific community is corrupt to the point of selling us all down the river for 30 pieces of silver. Nobody can be trusted .. they're all out to get us! Hell ... some scientists even have the audacity to state their conclusions that global warming mightn't be as dangerous as we're led to believe!! Can you conceive of that ... people having the gall to express an opinion other than the politically correct one?! My God! At this rate we'll have an outbreak of independence of thought!!

Soph, my comments were never meant to be derogatory towards you personally. I was simply trying to utilise your attitude towards atmospheric nuclear rocketry as part of my argument about public opinion and how difficult, if not impossible, it will be to change it.
What I was at pains to point out was that NuclearSpace was putting forward a hypothetical situation. He very carefully indicated he was talking about a scenario wherein new types of extremely clean low-yield bombs, fully tested and approved, might be used. What little radiation such bombs might produce would be so attenuated over such vast volumes of air and such enormous areas of, say, the Pacific Ocean, that the contribution to Earth's natural background radiation would be much too small to measure.
NuclearSpace wasn't saying 'to hell with the biosphere, let's just go ahead and detonate hundreds of filthy radioactive devices because I want to get us into space at any cost and I'm a right-wing lunatic who couldn't care less if the Earth I leave my children is a wasteland of pollution and poisonous isotopes'!
I feel this subtle point has been overlooked ... and that's what worries me.

Technology advances all the time. There's a constant stream of new data and new innovations. Things don't remain the same.
Just because a certain suggested means of getting 10,000 tonnes into Low Earth Orbit involves atmospheric nuclear explosions, that shouldn't result in a knee-jerk reaction of dismissal. Every proposal ought to be examined on its individual merits before a verdict is reached.
If the new proposal proves unsatisfactory after fair, transparent, and rational analysis, then by all means reject it.

All I was saying is that we're becoming almost superstitious about nuclear applications. I'm not interested in anything which is going to damage our beautiful planet and neither, I'm sure, is NuclearSpace. But for heaven's sake, let's put away the crucifixes, amulets, and necklaces of garlic and look at Orion critically but reasonably!
???

P.S. What's the range of an electro-magnetic-pulse from,
say, a 0.1 kiloton nuke? If we launch from a floating
platform a thousand kilometres from the nearest land, is
e.m.p. still going to be a problem? It seems most unlikely
to me but I'm ready to be proved wrong.

Shaun Barrett · 2002-12-13 20:10:12

Oops!
NuclearSpace and I have posted almost together on this. I hadn't read his post when I launched into mine.

soph · 2002-12-13 20:18:55

if there is a way to contain most of the radiation so that the fallout is very low, im all for it. 2 million tons is like a space carrier. almost like a mining town. 2 of those could be a permanent asteroid mining base. if it works, its beautiful. we could have thousands of people living in space, mining asteroids, harvesting helium 3, whatever.

but safety is the big issue. all that i care about is a level of containment. how effective would lead shielding be?

soph · 2002-12-13 20:47:21

thats some interesting information. price tag?

RobertDyck · 2002-12-13 21:28:25

Hello NuclearSpace. I would like your opinion of the idea of fission combustion. I posted a topic entitled "Liquid Fission Rocket" in "Interplanetary transportation". I could quote the topic starter, but it would be easier for you to read it there.

The idea is to take the advantages of Orion without the danger of explosions, or the inefficiency caused by most of the force being wasted into space. Contain the nuclear reaction, but create a continuous reaction rather than a pulse detonation. Chemical explosives create a pulse detonation from a chemical reaction, and an internal combustion engine contains a series of small fuel-air explosions to push the pistons; however a jet engine uses continuous combustion. Likewise I am suggesting creating a continuous nuclear fission reaction within a rocket engine. Containing the reaction would be more efficient so a less reaction rate should produce less radiation and less EMP. In fact, electromagnetic emission should be continuous rather than a pulse. Lower radiation and lower peaks should be better for both crew and onboard electronics.

This would operate similar to a gas core nuclear thermal rocket, but with greater reaction rate and greater emphasis on the nuclear reaction itself rather than heat generation. The fuel would primarily be fissile material stored in liquid form rather than reaction mass.

AltToWar · 2002-12-14 10:21:53

I fear AltToWar may suffer from terminal paranoia. It appears everything is bad in his book: Right-wing governments are out to enslave us and now the scientific community is corrupt to the point of selling us all down the river for 30 pieces of silver. Nobody can be trusted .. they're all out to get us! Hell ... some scientists even have the audacity to state their conclusions that global warming mightn't be as dangerous as we're led to believe!! Can you conceive of that ... people having the gall to express an opinion other than the politically correct one?! My God! At this rate we'll have an outbreak of independence of thought!!

If your not worried about our modern times, your not paying attention.

I am not worried about independant thought. It will always be here. I am worried about the suppression of thought. I am concerned when science conforms to politics.
http://www.guardian.co.uk/bush/story/0, … 50,00.html

Even trace amounts of radioactive materials that fall under the backround level of radiation accumulate to dangerous levels in biological organisims.

Insignifigant amounts of radioactive fallout were accumulated by lichens in the north pole. Lichens get their minerals from the air as opposed to the soil. Beause of this, trace amounts of radioactive materials were accumulated within lichens.

Caribu eat many times their weight in lichens.

When you come to the end of this food chain, Eskimoes diet is primarily made up of caribu. By this level of biological accumulation eskimos accumulate dangerous amounts of radiation within their bodies.

During nuke tests in Utah, a small cloud of fallout in the form of radioactive Iodine fell over some land populated by dairy farms. The amount of radiation in the open air was triviakl and hardly measurable over normal background levels.

Milk cows graze over this land. Another occurance of biological magnification took place. Even though the amount of radioactive iodine that fell on the grasses was insignifigant to cause any alarm, cows consume a very large amount of grass daily.

The iodine was passed on to children within utah. Another biological magnification took place, as Iodine within the humabn boy accumulates within the thyroid.

9 Children in this reletively unpopulated area were diagnosed with thyroid cancer 15 years after the fallout.

Phisicists are not biologists.

In a pond near Oak Ridge, the nuke lab there dumped some of it's low level waistes. The amount of radioactivty in this waiste was much much too low to be of any concern.

A study had found that the bones of the fish of this pond contained 10,000 times the amount found in the water.

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#1 2002-12-11 21:27:08

Re: Project Orion Revisited. - Why not an Earth Launch?

#2 2002-12-11 22:17:25

Re: Project Orion Revisited. - Why not an Earth Launch?

#3 2002-12-12 01:07:58

Re: Project Orion Revisited. - Why not an Earth Launch?

#4 2002-12-12 08:15:16

Re: Project Orion Revisited. - Why not an Earth Launch?

#5 2002-12-12 14:11:32

Re: Project Orion Revisited. - Why not an Earth Launch?

#6 2002-12-12 21:50:26

Re: Project Orion Revisited. - Why not an Earth Launch?

#7 2002-12-12 22:03:42

Re: Project Orion Revisited. - Why not an Earth Launch?

#8 2002-12-12 22:44:26

Re: Project Orion Revisited. - Why not an Earth Launch?

#9 2002-12-13 02:53:59

Re: Project Orion Revisited. - Why not an Earth Launch?

#10 2002-12-13 05:28:56

Re: Project Orion Revisited. - Why not an Earth Launch?

#11 2002-12-13 07:22:22

Re: Project Orion Revisited. - Why not an Earth Launch?

#12 2002-12-13 07:57:36

Re: Project Orion Revisited. - Why not an Earth Launch?

#13 2002-12-13 13:48:13

Re: Project Orion Revisited. - Why not an Earth Launch?

#14 2002-12-13 20:07:39

Re: Project Orion Revisited. - Why not an Earth Launch?

#15 2002-12-13 20:10:12

Re: Project Orion Revisited. - Why not an Earth Launch?

#16 2002-12-13 20:18:55

Re: Project Orion Revisited. - Why not an Earth Launch?

#17 2002-12-13 20:47:21

Re: Project Orion Revisited. - Why not an Earth Launch?

#18 2002-12-13 21:28:25

Re: Project Orion Revisited. - Why not an Earth Launch?

#19 2002-12-14 10:21:53

Re: Project Orion Revisited. - Why not an Earth Launch?

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