Ares and Ares

Dayton Kitchens · 2006-08-27 19:09:11

If the current Ares is too small for Mars Direct just do one of two things.

1) Build a bigger booster. Not hard. Just a matter of funding.

2) Go Mars Semi-Direct. Use three Ares launches to send the necessary equipment and crew for each Mars mission.

No show stoppers.

dicktice · 2006-08-27 20:14:25

I only tried to average out all of the ideas, to see if anything would come of it. The assembly space station was a last ditch suggestion, which I didn't think would survive a concerted reply. No, placing reactors of any kind in orbit is asking for atmospheric fallout, and eventual cessation by the popular acclaim of space launchings of any sort, period.

GCNRevenger · 2006-08-27 21:19:58

As long as the reactor is in orbit before startup, then its just fine. The majority of the radioactivity will dissapate on the order of a few decades; so as long as the thing is an orbit that won't decay over that time span then even if the core does melt down it won't come down on us until the radiaiton is mostly gone. Its activating the reactor before you reach orbit, as in the case of a nuclear upper stage, which is the problem.

Dayton has it basically right though. If your plan requires a relatively whimpy solid core nuclear engine, then your rocket is too small.

Even funding wise, a small rocket with a nuclear engine is going to cost about the same as a big rocket with chemical engines.

RobertDyck · 2006-08-27 22:22:24

NASA is currently looking at nuclear-electric propulsion. That means a nuclear reactor to produce electricity, then the electricity powers an electric engine. Electric engines could be ion, hall effect, Magneto-Plasma Dynamic (MPD), or VAriable Specific Impulse Magneto-plasma Rocket (VASIMR). The last two (MPD and VASIMR) have the advantage they use liquid hydrogen as propellant, the first two use heavy noble gasses: xenon or krypton. There isn't much xenon or krypton in Earth's atmosphere, and asteroids or the Moon don't have enough gravity to hold onto those gasses. Noble gasses are fine for small unmanned probes, but you need a lot of propellant for a manned vehicle; hydrogen is plentiful.

JIMO is the Jupiter Icy Moons Orbiter, also known as Jupiter Icy Moons Explorer. The plan was to send a multi-megawatt nuclear reactor to power an electric engine. It wouldn't be big enough for a manned vehicle, but a major step in development. It has encountered political opposition resulting in delays. Although Timberwind achieved 1000 second Isp, the Glenn Research Center has already tested in the lab an ion engine with over 8000 second Isp, and hopes to achieve 10,000 seconds. They're working on an improved MHD they hope will also have 10,000 seconds Isp, and the guy at Johnson Space Center working on VASIMR now got private funding to work on it outside NASA. He had hoped VASIMR would achieve 9000 second ISP. Although NASA had previously thought hall effect could only achieve 1,700 to 1,800 second Isp, they hired the Russians to tell them everything they did and learned the Russians had developed hall thrusters to equal NASA's ion thrusters. Thruster Anode Layer (TAL) hall thrusters had over 3,000 second Isp just before NASA launched Deep Space One. DS1 had slightly over 3,000 second Isp. GRS has increased Isp to 8,000 second by using a hell of a lot of power, you could do the same with hall thrusters to achieve the same result. Since ion and hall use the same propellant, they're effectively the same thing. Use different principles, but operationally the same.

This shows the direction NASA is now taking. Instead of using nuclear thermal rockets (NERVA or Timberwind) to go from Earth orbit to Mars, they intend to use weak thrusters that fire a long time but have extremely high fuel efficiency. But it still requires a nuclear reactor. To keep the reactor small and light you still have to use highly enriched uranium; read "bomb grade".

Tom Kalbfus · 2006-08-27 23:25:49

I only tried to average out all of the ideas, to see if anything would come of it. The assembly space station was a last ditch suggestion, which I didn't think would survive a concerted reply. No, placing reactors of any kind in orbit is asking for atmospheric fallout, and eventual cessation by the popular acclaim of space launchings of any sort, period.

Oh, that's great! All we have to do is launch a nuclear rocket and have an accident spilling radioactive contamination into the atmosphere and suddenly a World Government forms that is democratically elected, all the worlds dictators will fall and popular acclaim will matter and they'll say no more space flights. :twisted:

If that were only true, then it would be worth the nuclear accident, but its not. the world is not completely run by democratic countries. If we give up on space, their are dictatorships in China, and Russia that would only be glad to conquer space instead of us, using whatever technology is available. If we cede the space race, someone else will win. I'm glad the Chinese have got an astronaut program, not because I want them to beat us to Mars, but because we need them to drive us to pick up our pace or lose the race. Do you think it all depends on the US Congress and who gets elected there? Not anymore, NASA is not the World Space Agency, and I think the rest of the World is no longer going to take a back seat to it, if it slacks off. Our time for fiddling around and going in circles in space is over. If their is an avenue we could try to get into space more cheaply, we should try it. in short, we should think outside the box, that's how scaled composites got into space after all. I think for the last 30 years, NASA has had a bad case of conventionalitis we need ways to get to Mars cheaply. Billion dollar footprints are not acceptable, this is the 21st century, and some people are prepared to remain stuck on this planet for the next 100 years, and I think we need to get off this planet for our own safety. Look at the world today, religious fanatics, terrorism, the spreading of nuclear bomb technology. Seems like Russia and China are no longer interested in preventing nuclear proliferation, so the cat's out of the bag, we might as well build Orion spaceships since more and more countries are going to get nuclear weapons anyway, and the more that have them the more likely they'll be used. So long as nukes threaten our very existance, I think we should try to get some positive use out of them while we still can.

I think it will not matter if we have not used Orion spaceships to spread radioactive contamination in the atmosphere if we then have a nuclear war. I think its only a matter of time, no one's stopping North Korea, no one's stopping Iran, or Venuzualia, no one wants to help the United States in curbing proliferation, because they want to give us a "black eye" by letting a few of our enemies gain nuclear weapons to threaten us with, that of course means more countries will have nukes and nuclear war will be more likely. if we just fiddle and let thing go on as they are, we will all be sorry.

Chemical rockets have not gotten off this planet in signifiant numbers, the have instead made billion dollar foot prints on the Moon, and we need to do more than this, even Stephen Hawking thinks this is so.

GCNRevenger · 2006-08-28 06:04:25

NASA is currently looking at nuclear-electric propulsion. That means a nuclear reactor to produce electricity, then the electricity powers an electric engine. Electric engines could be ion, hall effect, Magneto-Plasma Dynamic (MPD), or VAriable Specific Impulse Magneto-plasma Rocket (VASIMR). The last two (MPD and VASIMR) have the advantage they use liquid hydrogen as propellant, the first two use heavy noble gasses: xenon or krypton. There isn't much xenon or krypton in Earth's atmosphere, and asteroids or the Moon don't have enough gravity to hold onto those gasses. Noble gasses are fine for small unmanned probes, but you need a lot of propellant for a manned vehicle; hydrogen is plentiful.
JIMO is the Jupiter Icy Moons Orbiter, also known as Jupiter Icy Moons Explorer. The plan was to send a multi-megawatt nuclear reactor to power an electric engine. It wouldn't be big enough for a manned vehicle, but a major step in development. It has encountered political opposition resulting in delays. Although Timberwind achieved 1000 second Isp, the Glenn Research Center has already tested in the lab an ion engine with over 8000 second Isp, and hopes to achieve 10,000 seconds. They're working on an improved MHD they hope will also have 10,000 seconds Isp, and the guy at Johnson Space Center working on VASIMR now got private funding to work on it outside NASA. He had hoped VASIMR would achieve 9000 second ISP. Although NASA had previously thought hall effect could only achieve 1,700 to 1,800 second Isp, they hired the Russians to tell them everything they did and learned the Russians had developed hall thrusters to equal NASA's ion thrusters. Thruster Anode Layer (TAL) hall thrusters had over 3,000 second Isp just before NASA launched Deep Space One. DS1 had slightly over 3,000 second Isp. GRS has increased Isp to 8,000 second by using a hell of a lot of power, you could do the same with hall thrusters to achieve the same result. Since ion and hall use the same propellant, they're effectively the same thing. Use different principles, but operationally the same.
This shows the direction NASA is now taking. Instead of using nuclear thermal rockets (NERVA or Timberwind) to go from Earth orbit to Mars, they intend to use weak thrusters that fire a long time but have extremely high fuel efficiency. But it still requires a nuclear reactor. To keep the reactor small and light you still have to use highly enriched uranium; read "bomb grade".

For probes and way-down-the-road missions perhaps, but NASA would be a fool not to use chemical propulsion for early missions. Replace the J-2 with a cluster of RL-60 on Ares-V, stretch the EDS tank and eliminate the LSAM, perhaps use a much smaller shroud to cover a much smaller docking bus... viola', send it up, stick an 80-90MT vehicle on the front launched seperatly, and we're on the way to Mars.

GCNRevenger · 2006-08-28 06:34:25

Or another option... launch the no-lander EDS with stretch oxygen tank but leave the Hydrogen alone except for a valve that would isolate the empty Hydrogen tank. Then launch your Mars ship on a second flight with a 25MT Hydrogen tank on the back, mate the EDS and the ship, and use the fresh Hydrogen instead. This gives you about 155MT of total cryogenic propellant, and would make up for the lower efficiency of the J-2X versus other engines (eg RL-60), reducing the need to modify the EDS stage. Perhaps increase the payload a little bit too, and greatly reduces the boiloff problem as LOX is about six times as stable.

dicktice · 2006-08-28 07:19:26

Re. "... stick an 80-90MT vehicle on the front launched seperatly, and we're on the way to Mars."

Where are you when you stick it on? In LEO, alongside the ISS, or ...?

GCNRevenger · 2006-08-28 07:21:45

Just like the Lunar missions, launch the EDS with extra oxygen into equitorial low earth orbit, then launch the Mars ship with the Hydrogen seperatly on a second standard Ares-V. Mate the two in orbit and off you go, of course no ISS involvement, there is no reason to.

dicktice · 2006-08-28 08:08:23

Heh, heh, I knew that!

Great, to get off the subject of atomic threats in the atmosphere. I've read and re-read Nevil Shute's "On the Beach" which I claim to have prevented nuclear back in the 1950's when we were all working flat out on ICBM warheads, just before Sputnik went up. Things really turned around, then!

Your second option went right over my head, what with all the acronyms: They certainly proliferate! Mind going over that gain, in a little more detail?

I just heard a local radio interview with Bigelow, visiting here, on the CBC (meaning it was broadcast nationally). He sounded quite congenial and open, and young enough to be into commercial space for the long haul. We're quite space oriented, up here in Nova Scotia on the 45th parallel. Also just reported, the Atlantis is being taken out harm's way, down there in Florida where the winds blow and the lightning strikes tend to hold up the space effort.

Also, the latest air transport crash down south has been attributed to using the wrong runway. I've flown in that plane in the past, a Canadian type, between Atlanta and Toronto. It was a typical Murphy's Law situation, which shows how easy it is to get yourself killed when your mind isn't on the job, even without the @#$&* terrorists to help Murphy along, eh?

RobertDyck · 2006-08-29 07:01:10

And, how far up does the atmosphere, not to mention the ionosphere, "end." I can remember when the distribution of radioactive dust (or whatever, I'm too busy to look it up just now) in the upper atmosphere, surprised scientists by how long lasting the damage (to what, communications?) lasted.

You're talking about a test in the 1962 that exploded a 1.4 megaton thermonuclear bomb at 400km altitude, the same altitude as ISS. At that time they bounced radio off the ionosphere, permitting over-the-horizon communication. Their test disturbed the ionosphere, it was intended to disrupt communication, but the effect spread globally rather than regional, and it lasted much longer than anyone expected. Today we don't count on the ionosphere, that effect would have little impact on high frequency communication to satellites and no impact on undersea cables or terrestrial fibre optics. That test created an EMP that knocked out street lights, radio stations, telephones for a time in a vast region beneath the blast. Everywhere in the Pacific VHF was disrupted for half a minute. Intense radiation belts lasted months and crippled satellites in LEO.

A hot reactor falling to Earth would not create EMP. It wouldn't spread radiation unless it burnt up in the atmosphere, which means the radiation wouldn't stay in orbit. The fallout would have to be compared to Chernobyl, not Starfish Prime.

Tom Kalbfus · 2006-08-29 08:25:02

What about the atomic fission bombs used in an Orion spaceship? I think they were supposed to have a yield of about one tenth of the Hiroshima bomb.. Say you have a conventional stage that lifts it up to a 400 mile altitude and detatched then it starts using its pulse units to go higher and to achieve orbit.

RobertDyck · 2006-08-29 11:27:51

Orion will never happen. The countries of the world will not let anyone lift nuclear bombs into space no matter what the reason, no matter who does it, no matter what the controls. It's far too easy for someone to deliberately drop one of those bombs onto a city.

GCNRevenger · 2006-08-29 12:21:59

Orion has unusual performance characteristics, cheifly that in order to obtain really superior efficiencies and thrust the vehicle has to be really big, especially the heavy pusher plate. If you can't use the bombs to lift off, which would obliterate the the launch facilities so it could not be reused, then you have to launch the thing by conventional rockets first. This severely limits the size of a practical pusher plate, and thusly limits its performance to no better than other fission engines of comperable difficulty (GCNR, NSWR).

Also, building atomic bombs is a difficult and expensive business, the cost of all those warheads would be utterly ruinous if you ever intended to use Orion on a regular basis. Plus, these bombs would have to be new, with a directed radiation case design, and more reliable than any modern weapon, since the consequences of premature detonation would be catastrophic. Also, if one or more bombs is a "dud" or the feeder mechanism fails during use, the ocillatory motion of the shock absorber without bomb blasts to push against could wreck the ship.

All this adds up to an extremely expensive vehicle with little or no performance edge versus other engines that you could not use on a regular basis. And oh yes, the "its a nuclear howitzer" problem.

Tom Kalbfus · 2006-08-29 13:13:02

Yes, but could China build one? China has nuclear weapons and is in the process of expanding its nuclear arsenal. Seems to me that China sould easily have an expanding supply of fission bombs because it is building the factories to make them anyway Orion is not a long term solution, but it does get a longerm space transportation system out the door. You say that Orion has to be very big to get out the door. Doesn't that also mean that it would be very good at delivering a mass driver to the Moon's surface? A Mass Driver is very big and if there is one ship that could get one to the Moon's surface, it would be the Orion. Nuclear weapons are dangerous, and you don't want to rely on them long term. In another threat I mentioned using a mass driver as a means to propel suborbiters in space up to orbital velocities using a mass driver hurtling lunar material to just above the Earth's atmosphere. If the suborbiter can get above the low point and has a means of vaporizing the incomming pellet stream, the gases produced can propel the suborbiter into orbit, but this sceme requires that first massive infrastructure be placed on the Moon first, and to do that, you need a heavy robust lifter and mover such as the bomb propeller Orion spaceship.

As for being expensive, China has the worlds fastest growing economy, if that trend continues, it will shortly be one of the World's leading superpowers, I'm sure it will be able to afford to build an Orion. If the Orion fails, the the Chinese build another one. The Chinese have expended more human life in the Korean War, I doubt it would make such a fuss about an Orion spaceship that fails, it will most likely learn from that failure and build another one if its determined to get ahead of the US in a space transportation system.

China is also good in public private partnerships, the nature of Orion virtually requires that it be operated by the government. China has a number of public owned companies that are run as if they were capitalistic enterprises, these engage in joint projects with foreign companies and are used to acquire western technology that it otherwise not have access to. The Chinese People's Army also engages in manufacturing work and makes items for sale to places like Walmart. I'm sure with that experience, the Chinese would be well prepared to operate the Orion efficiently and profitably while keeping the nuclear weapons it uses under tight military control.

There are many schemes for cheap access to space that first require lifting massive infrastructure there, Orion seems like a good spaceship to get the ball rolling.

Orion will never happen. The countries of the world will not let anyone lift nuclear bombs into space no matter what the reason, no matter who does it, no matter what the controls. It's far too easy for someone to deliberately drop one of those bombs onto a city.

The countries of the world don't seem too concerned about Iran getting nuclear weapons do they. If anyone is crazy enough to use nuclear weapons in a terrorist attack, it would be Iran, yet the nations of the world aren't doing much to stop them except calling for more negotiation. If Iran can aquire nuclear weapons and the world is mostly concerned about the US invading them to stop them, won't that lead the Chinese to believe that they could also get away with building an Orion spaceship as well? Why should the world suddenly develop backbone in this case where it hasn't in the case of Iran or North Korea. I think the most China would have to worry about is the world sending out negotiators while at the same time ruling out the use of force and the imposition of sanctions, they will want to give negotiations a chance to work, and they negotiate and negotiate and negotiate, and China will stall and stall and stall until it builds and launches its Orion Spaceship, I can easily envision China getting away with that, can't you?

If the worlds western democracies are too timid to conquer the Solar System, then China will conquer it instead.

dicktice · 2006-08-29 17:05:36

I can't tell if you're bragging or complaining about China.

John Creighton · 2006-08-29 20:32:27

China building an Orion type space ship? If anything would start a space race that certainly would. Probably at an economically devastating scale. Could China build such a ship? Could the US build such a ship? I don’t see this happening tomorrow. I think the first steps into space will be much more modest and sure footed then a thermal nuclear explosive leap. We haven’t even learned how to use space resources that well. Do we really want to start hurling up thousands of tons in one shot spewing radiation in our exhaust. Don’t forget an Orion ship can’t land and we know how good we are at building space stations

Tom Kalbfus · 2006-08-30 00:35:54

Economically Devastating eh? You think their will be no return on the investment which allows easier access to the Solar System. You know the Orion, can not only reach the Moon and Mars, it can also reach Titan, it would open up the whole Solar System more or less! There is alot of material in the Whole Solar System. Investing in a way to get off of Earth is not money down the drain. I don't see those timid steps into space as sure footed, I just seem them as a lack of progress. I think the way to get into space has been before our eyes all along, but we just refused to look at it because of the anti-nuclear taboo. Instead of trying to deal with the problems that nuclear propulsive systems would cause and try to solve them, se simply refuse to deal with them period and have been using the much more expensive throw-away high performance chemical rockets instead. The Venture Star was to be made out of Carbon Composites, so 90% of its mass could be fuel, and we ran into problems with making fuel tanks out of such composites to hold liquid oxygen. By contrast, the upperstage of the Orion wouldn't hold cryogentic liquid fuels, but would hold a magazine of minature atomic bombs instead in the 1 kiloton range of explosive yield. The Orion would have been made out of ordinary steel.

Tom Kalbfus · 2006-08-30 00:47:21

I can't tell if you're bragging or complaining about China.

I am stating what China might do. Why should I complain about China, its part of the nature of Empires to want to expand. All the territory outside of Earth is uncontested, their are no armies to defeat out their, you merely need to develop the transportation system and get there first and in great numbers, China is not hindered as much by public opinion as we are. If we have a carefully plodding space program, I believe China will try to leap over us. Prior to China's entry into the space race, NASA was pretty much alone is manned space efforts, Russia was bankrupt and was basically selling launch services rather than doing anything on its own. NASA was in the driver's seat as far as Manned space is concerned. With China's launch of astronauts into orbit, now that is no longer true. China likes to do big things, it is building huge dams, it has built the first commerically operated Maglev train, I think it very much would like to get to Mars ahead of the USA, all this has much to do with the ego of China's leaders rather than specifically what the Chinese people want, althought they are very patriotic. Their is no opposition leader to say that manned space is a waste of money that could be better spent elsewhere, the Chinese leadership doesn't face that competiton. The nation that seizes the Space bull by the horns will have lasting influence in the Solar System from that point on.

RobertDyck · 2006-08-30 05:15:44

Land on celestial bodies is contested; that was the point of the Outer Space Treaty of 1967.

Article II
Outer space, including the moon and other celestial bodies, is not subject to national appropriation by claim of sovereignty, by means of use or occupation, or by any other means.

China and USA are signatory nations.

References:
Out Space Treaty breaf description including map of nations that signed and ratified or just signed it.
Outer Space Treaty of 1967 full text with bookmark to article II.

Grypd · 2006-08-30 05:41:45

There is two problems that come from China trying an Orion project approach.

1) China would have to invest heavily on the research needed to create such a vehicle and it would be politically and financially expensive. They would have to research the use of small nuclear devices and this would not be that popular in there goverment. Especially when this would have to come from there military build up.

2) What would it gain them to make such a vehicle they cannot access the riches of the solar system since they do not have the skills to utilise the materials nor have an economical way to return to Earth with these. They cannot claim ownership of any of the bodies they land on and they would have a lot of research to do just to survive out there. In short they are far from being able to do what you have stated.

GCNRevenger · 2006-08-30 07:28:48

Economically Devastating eh? You think their will be no return on the investment which allows easier access to the Solar System. You know the Orion, can not only reach the Moon and Mars, it can also reach Titan, it would open up the whole Solar System more or less! There is alot of material in the Whole Solar System. Investing in a way to get off of Earth is not money down the drain. I don't see those timid steps into space as sure footed, I just seem them as a lack of progress. I think the way to get into space has been before our eyes all along, but we just refused to look at it because of the anti-nuclear taboo. Instead of trying to deal with the problems that nuclear propulsive systems would cause and try to solve them

You aren't listening

Orion is not practical to do anything except visit, because you can't have a perminant launch site. You can't build a Cape Canaveral for Orions. The infrastructure required to support a space program that does more than visit will have to have such a support complex, but you can't if you detonate nukes to lift off or land, even small ones. That is assuming that you can land an Orion ship at all, where if the minimum separation between ship and bomb is greater than your altitude, then you'll never come back down even if you were permitted to. And how do you maneuver a vehicle of that size and mass?

Also, small bombs make comperable amounts of fallout as bigger ones. There is a minimum amount of fuel required to make any bomb explode, and small bombs are just big bombs that are intentionally inhibited to limit their yeild. There is still lots of radiation, this is not trivial.

The cost of small, ultrareliable bombs is also quite high, a magazine full of hundreds of them would easily cost several billions of dollars in production costs only, much less development. Is this really any cheaper than launch by large chemical rockets?

It would not "open up the solar system," even if it did work it would never be practical except the rare one-off flight. Orion never got anywhere between Orion would never get anywhere.

If you want a superhigh performance nuclear engine, look at the GCNR or NSWR rockets, or perhaps even VASIMR fed by a vapor-core reactor (VCR). The GCNR engine imparticular is my favorite, though relatively exotic it has performance roughly comperable to a small Orion ship with a minimum of nuclear fuel and risk.

Tom Kalbfus · 2006-08-30 10:43:23

Orion's can't land eh? What is required to land on Earth's surface, lets look at the Saturn V space craft for example. Saturn V had this huge stack of rocket stages to boost the vehicle to beyond Escape velocity to get them to the Moon, insert them into orbit, land on the Moon, take off again, and insert on a return to Earth trajectory. The Apollo capsule returned to Earth at about the same velocity that it left it at, only on return, it was just a command module and a capsule. What the apollo capsule needed to land was to reduce its incoming velocity to that of the surface of the Earth before it hit that surface, to do that, it didn't rely on a huge stack of rocket stages as it did for the outbound leg, instead, it relied on the Earth's atmosphere and parachutes to slow it down. Now why are you assuming that the Orion would uses a series of atomic bomb explosions to make a soft landing on Earth's surface, that assumption was never made that Saturn would use its rocket engines to land on Earth?

The trick to the Orion Spaceship is to get it down to Earth's surface so that it could be prepped for another mission, to do that it would not use its nukes, instead, it would rely on an areoshell and heat shield and use the atmosphere to do most of its braking, and then as it approached the ground, it would use chemical landing rockets to make the soft landing. I would think that would be obvious. The bottom chemical stage that lifted the Orion Rocket in the first place into space, would be recovered fueled and prepped for Launch, the Orion would be placed atop of this booster and given another load of atomic bombs to use and the Orion would then be ready for another mission. Landing is not really the hard part as the Earth has an atmosphere to do most of the braking, the fuel for the landing rockets is miniscule compared for the fuel required to reach space and the atomic bombs required to reach orbit and beyond. All that's really needed for landing on Earth is a heat shield, a parachute and/or landing rockets. The Orion is fairly massive, so it will probably rely on only landing rockets to slow its fall at terminal velocity to make a soft landing on the ground.

GCNRevenger · 2006-08-30 11:17:22

But if you were to launch Orion into orbit with chemical rockets, this limits the practical size of the pusher plate, and eliminates all its advantages over other nuclear rockets with far cheaper and less controvertial fuel. The NSWR engine could easily out-perform a "mini" Orion, and GCNR would match it. The former powerd by Uranium Nitrate or Bromide and water with the latter powerd by plain old liquid Hydrogen. Plus these options, particularly GCNR, would not have an extremely massive pusher plate and shock absorber, radically improving their payload versus Orion. Not to mention that if you could refuel either NSWR or GCNR rockets using water or Hydrogen from other planets, you could increase their payload even more. And did I mention that there would be no political "fallout" from putting a working nuclear bomb launcher in orbit?

Landing Orion is a bigger problem then you make it sound too, a steel pusher plate would literally melt from the heat of reentry, plus it is all the wrong shape if you intend to use it as a heat shield. Bringing a heat shield big enough to protect the whole vehicle, including the big wide pusher plate, would be quite heavy and eliminate even more of Orion's supposed efficiency.

If you intend to use the pusher plate as the heat shield, this has several more problems: it would probably have to be made with an ablative coating to protect it from the heat, but this coating would burn off from normal "operation" of the engine. Replacing and refurbishing this shield would be difficult as it would be quite radioactive from the neutron flux or embedded daughter particles from the bombs. X-33 managed to get away with a lighter reuseable shield because it was so light compared to its volume, the opposit of Orion.

It is also all the wrong shape, you would want a shield that is fairly convex as it faces the atmosphere, but to efficiently "catch" the plasma wave from the bombs it has to be concave. Making it concave would produce a "hot spot" in the middle that would melt through just about anything I bet, and increase the deceleration rate to dangerous levels.

Parachutes would also be a problem, as your speed drops from orbital the heat shield would be less effective at slowing you down, so you would need parachutes. Too bad the parachutes would have to be rediculously large to slow down something the weight of Orion. Certainly bigger than a sports stadium.

And thats just to get you down. Why should we bother with this again?

Mars_B4_Moon · 2006-08-30 11:23:43

Yes, but could China build one? China has nuclear weapons and is in the process of expanding its nuclear arsenal. Seems to me that China sould easily have an expanding supply of fission bombs because it is building the factories to make them anyway Orion is not a long term solution, but it does get a longerm space transportation system out the door. You say that Orion has to be very big to get out the door. Doesn't that also mean that it would be very good at delivering a mass driver to the Moon's surface? A Mass Driver is very big and if there is one ship that could get one to the Moon's surface, it would be the Orion. Nuclear weapons are dangerous, and you don't want to rely on them long term. In another threat I mentioned using a mass driver as a means to propel suborbiters in space up to orbital velocities using a mass driver hurtling lunar material to just above the Earth's atmosphere. If the suborbiter can get above the low point and has a means of vaporizing the incomming pellet stream, the gases produced can propel the suborbiter into orbit, but this sceme requires that first massive infrastructure be placed on the Moon first, and to do that, you need a heavy robust lifter and mover such as the bomb propeller Orion spaceship.
As for being expensive, China has the worlds fastest growing economy, if that trend continues, it will shortly be one of the World's leading superpowers, I'm sure it will be able to afford to build an Orion. If the Orion fails, the the Chinese build another one. The Chinese have expended more human life in the Korean War, I doubt it would make such a fuss about an Orion spaceship that fails, it will most likely learn from that failure and build another one if its determined to get ahead of the US in a space transportation system.
China is also good in public private partnerships, the nature of Orion virtually requires that it be operated by the government. China has a number of public owned companies that are run as if they were capitalistic enterprises, these engage in joint projects with foreign companies and are used to acquire western technology that it otherwise not have access to. The Chinese People's Army also engages in manufacturing work and makes items for sale to places like Walmart. I'm sure with that experience, the Chinese would be well prepared to operate the Orion efficiently and profitably while keeping the nuclear weapons it uses under tight military control.
There are many schemes for cheap access to space that first require lifting massive infrastructure there, Orion seems like a good spaceship to get the ball rolling.
Orion will never happen. The countries of the world will not let anyone lift nuclear bombs into space no matter what the reason, no matter who does it, no matter what the controls. It's far too easy for someone to deliberately drop one of those bombs onto a city.
The countries of the world don't seem too concerned about Iran getting nuclear weapons do they. If anyone is crazy enough to use nuclear weapons in a terrorist attack, it would be Iran, yet the nations of the world aren't doing much to stop them except calling for more negotiation. If Iran can aquire nuclear weapons and the world is mostly concerned about the US invading them to stop them, won't that lead the Chinese to believe that they could also get away with building an Orion spaceship as well? Why should the world suddenly develop backbone in this case where it hasn't in the case of Iran or North Korea. I think the most China would have to worry about is the world sending out negotiators while at the same time ruling out the use of force and the imposition of sanctions, they will want to give negotiations a chance to work, and they negotiate and negotiate and negotiate, and China will stall and stall and stall until it builds and launches its Orion Spaceship, I can easily envision China getting away with that, can't you?
If the worlds western democracies are too timid to conquer the Solar System, then China will conquer it instead.

I read this type article before
http://www.rattlesnake.com/notions/chinese-orion.html
I'm not sure how much is true and how much is alarmist hype

but a Chinese Project Orion would certainly get people's attention

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