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#76 2006-09-02 07:30:42

GCNRevenger
Member
From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: Ares and Ares

A more practical Orion would be one that used pure fusion bombs. I think the only find of fusion rocket that would work in Earth's atmosphere would be the pulse fusion variety. So the main trick here is to create a fusion trigger without fissionables. I think a good candidate would be stored antimatter. If you could get a small amount of antimatter to trigger a cascade fusion reaction that detonates all the fusion fuel within the bomb, then you would have no radioactives heavy elements left over, The antimatter is completely gone afterwards and the best thing about it is that antimatter/matter reactions have no critical mass requirements, you can annhilate any small amount.

No. Antimatter by itself can't initiate the reaction in a practical way. You throw some antimatter at a container of fusion fuel, and all you get is a container of fusion fuel blown to bits without accomplishing anything. Remember, for a bomb to detonate, it has to remain together as a single piece for a little while for the fuel to "burn" efficiently. Blasting antimatter into the middle of a fusion bomb will just make it explode outward immediatly. Fusion bombs work by compressing the fuel, todays' weapons are thought to work by X-Rays from the fission primary trapped within the radiation case heating the tamper thats surrounding the fusion fuel secondary from every direction. You'd need an awful lot of antimatter to start such a reaction anyway.

Nor is antimatter and fusion totally clean either; antimatter generates large amounts of very high energy gamma rays that will be difficult to protect Orion's crew/cargo from, then you have the antimatter inducing fission of the non-fuel part of the bombs that will leave fallout too, and lastly the large amounts of neutron radiation generated by the fusion bombs themselves would make anything nearby radioactive.

Producing or storing antimatter in the quantities required would not be easy, and this difficulty combined with the deveopment of the fusion bombs (even if they did work) plus building some kind of nuclear-bomb-proof Cape Canaveral for Orions replete with antimatter storage facilities, would still cost alot more than just building & flying three or four Sea Dragons or NOVA's for every Orion and developing one of the other nuclear thermal rockets.

And then you have the safety issues with antimatter, that atomic bombs you can trust not to accidently detonate because it is such a delicate thing to make them detonate in the first place, so it isn't really a safety hazard. Antimatter on the other hand, is just itching to get loose and blow up. If Orion springs a leak, then it would probably blow a nice hole in the side of your ship and deprive you of maneuverability.

Nor does this really solve the issue that it would still make a really nice weapon, since those bombs still make ionizing radiation, they could still lay down a hugely powerful EMP effect over an enemy country in minutes, sending them back to the stone age militarily and economically. In fact, that would increase the likelyhood someone would want it for a weapon and how much international political resistance it would encounter, not reduce it.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#77 2006-09-02 08:56:48

Tom Kalbfus
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Posts: 4,401

Re: Ares and Ares

Any spaceship with science fiction properties of being able to take off from a planet's surface and then land on a planet's surface and then take off again would make a nice weapon in any case, as we don't have stuff like that. Seems to me the most efficient way to get into space is to use a conveyor-like system such as a space elevator or a space fountian requiring massive fixed infrastructure. The idea of a single space ship that can take off from earth's surface and head to orbit  while remaining in one piece and yet still have plenty of fuel for maneuvering is a science fiction staple, any way you cut it, its going to make a good weapons platform. Also the energy requirements for it to do so while concerving reaction mass in a rocket are quite high, what you really need is a high thrust fusion rocket to do that stuff.

Magnetic confinement, I afraid doesn't work in Earth's atmosphere. You can have a magnetic bottle in a vacuum chamber and initiate fusion within, but in order for it to be a rocket, you need fusion and also for that magnetic bottle to leak out some of that plasma, but if you do that, the atmosphere will rush in and cool the plasma to below fusion temperatures. What you really need is a pulse fusion rocket, that at one time undergoes fusion and at another time leaks out pushing the rocket forward. Inertial confinement fusion seems the best candidate for this and bombs are the most readily available means for doing it. :aser pellets might do it, but the lasers are massive and the pellet explosions are small, I'm not sure sufficient acceleration can be achieved to get such a rocket off the ground. What you really need is a self-contained fusion device, or in otherwords a bomb. If you can somehow get rid of the fission trigger or use an element whose critical mass is much less than plutonium, then you don't have the plutonium bottleneck to contend with.

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#78 2006-09-02 12:29:53

GCNRevenger
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Posts: 6,056

Re: Ares and Ares

Orion is still unique though, because:

  • ~Fire rate, it will be able to despense 100s of warheads in a single orbit
    ~Responsiveness, VASIMR and GCNR engines take a little time to power up, but bombs are immediate
    ~Invunerability, due to the above and the thermal properties of the pusher plate, no Earth-based weapon could harm Orion unlike other options
    ~Excuse, to build a large arsenal of tactical nukes

I'm not sure sufficient acceleration can be achieved to get such a rocket off the ground

No pellet-fusion engine would have enough thrust to support its own weight, much less take off.

What you really need is a self-contained fusion device, or in otherwords a bomb. If you can somehow get rid of the fission trigger or use an element whose critical mass is much less than plutonium, then you don't have the plutonium bottleneck to contend with.

There is no such thing as a pure fusion bomb with no fission trigger, and such a thing might not be possible.

Plutonum-239 is already about the best there is, and its the only economical one anyway. No other element would be much better, and no other element is available in quantity either.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#79 2006-09-02 12:52:31

RedStreak
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Posts: 541

Re: Ares and Ares

WHAT THE HECK DO NUCLEAR ENGINES HAVE TO DO WITH THE ARES ROCKET FOR CRYING OUT LOUD?!  I HATE TO BE A FREAKING FORUM NAZI OVER THIS BUT THIS ISN'T THE RIGHT FORUM!!

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#80 2006-09-02 13:14:53

RedStreak
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Posts: 541

Re: Ares and Ares

If you're talking about nuclear propulsion with the Ares stick to what Zubrin originally talked about: a nuclear stage for Mars Direct, and I am glad a few of you have made mention of this.

I don't approve of even Zubrin's idea of using such a stage.  Nuclear material...is not disposable.  We're talking abou a rocket engine loaded with radioactive material that could kill a human being.  Yes space itself is loaded with radiation and we could shield the crew from it but what happens if one of these spent stages, empty of fuel but damn-well loaded up on still-simmering uranium rods finds its way hurtling back toward Earth?

The Galileo spacecraft which also carried nuclear material in its RTGs was intentionally burned up in Jupiter's atmosphere to prevent any contamination of Jupiter's moons, and there are talks of the same fate happening to Cassini for the same reasons.

Can any of the deep space tracking systems keep an eye on a spent interplanetary stage constantly?  If the answer is no then there's no way we can put nuclear material into an expendable stage or even should.

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#81 2006-09-02 17:01:36

Tom Kalbfus
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Re: Ares and Ares

If you're talking about nuclear propulsion with the Ares stick to what Zubrin originally talked about: a nuclear stage for Mars Direct, and I am glad a few of you have made mention of this.

I don't approve of even Zubrin's idea of using such a stage.  Nuclear material...is not disposable.  We're talking abou a rocket engine loaded with radioactive material that could kill a human being.  Yes space itself is loaded with radiation and we could shield the crew from it but what happens if one of these spent stages, empty of fuel but damn-well loaded up on still-simmering uranium rods finds its way hurtling back toward Earth?

It won't be, it will be hurling away from Earth instead. The nuclear stage won't be fired up until after orbit is achieved and it that case it will be leaving Earth orbit. If it somehow fails in the outbound leg it will be in an elliptical orbit around the sun or in an elliptical orbit around Earth, its low point will be in low Earth orbit if the later, it the former it will become one of the Near Earth Objects, chances are, when in comes back to 1 AU from the Sun, the Earth won't be there and there are many other near Earth asteroids that will be likely to hit Earth before that stage does. The Earth isn't the biggest thing in the Solar System after all, and if a little bit of plutonium reenters the atmosphere after thousands of years of orbiting the Sun so what? I think you exagerate the effects of a little plutonium in the atmosphere, it doesn't spell doom for all life on Earth. One of the Near Earth asteroids is likely to cause more harm if it hits the Earth than a spent nuclear stage.

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#82 2006-09-02 18:59:09

RedStreak
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Posts: 541

Re: Ares and Ares

It won't be, it will be hurling away from Earth instead. The nuclear stage won't be fired up until after orbit is achieved and it that case it will be leaving Earth orbit. If it somehow fails in the outbound leg it will be in an elliptical orbit around the sun or in an elliptical orbit around Earth, its low point will be in low Earth orbit if the later, it the former it will become one of the Near Earth Objects, chances are, when in comes back to 1 AU from the Sun, the Earth won't be there

Small problem.  There are cases of Saturn V stages also entering solar orbit and reutrning.  If that's not an example you want to consider the TV show Futurama made a comical note of a giant garbage ball launched into space and then threatening to destroy New New York City a thouand years later.  Even if it's a thousand years into the future I'd rather not have my descendents spitting on my grave after a nuclear stage crashes into their municipal public pool.


The Earth isn't the biggest thing in the Solar System after all, and if a little bit of plutonium reenters the atmosphere after thousands of years of orbiting the Sun so what?

I think you're missing my point.  We need to be responsible with what we take out there.  The easiest way to get ride of any risk is not to take it.  We only dispose of rocket stages because it is safe and cost-effective.  Working with a nuclear rocket stage is neither.

I think you exagerate the effects of a little plutonium in the atmosphere, it doesn't spell doom for all life on Earth.

So did Chernobyl and Hiroshima and Nagasaki beforehand.  A little goes a long ways.  Plutonium isn't even a naturally occuring element - it has to be refined from Uranium.

I can't deny that using a nuclear rocket would boost paylod capacity and might cut speed, but if we use one of these things we should not jettison it like random garbage, because it isn't random garbage.  We are talking about a nuclear reactor core modified into a rocket.

........

Hell, just the sound of it isn't good: nuclear reactor AS a rocket?!

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#83 2006-09-02 21:15:08

GCNRevenger
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Posts: 6,056

Re: Ares and Ares

Nuclear material...is not disposable

False. There are two all-important facts about radioactive material that environmentalists have sucessfully convinced everyone are not true.

  • -There is a such thing as a safe dose
    -The intensity and longevity of radioactivity are inversely proportional

These things are true.

The two practical nuclear fuels, Uranium 235 and Plutonium 239, have extremely extremely long longevities. Note that these are not Plutonum 238 nor Uranium 233 and 238 which are not nuclear fission fuel and have much shorter longevities. Pu 239 and U 235 have longevities in the tens of thousands of years. Because the length of time and intensity of radioactivity are inversely proportional, this means - and this is by all measures and meanings of anything scientific fact - that they are not appreciably radioactive. This means that if a substance is radioactive for a very long time, then its radioactivity has such weak intensity that it is negligable.

Fresh fuel is not radioactive. The Canadian CAN-DU reactor fuel rods are loaded with Uranium powder by hand with kitchen gloves. French MOX (Uranium and Plutonium) fuel assemblies are shielded with plastic wrap, and thats mostly to keep them clean. You can walk right up and hug a fresh fuel assembly even. Again, fresh nuclear fuel is not dangerously radioactive. You could take an entire reactor full of fresh fuel, grind it into dust, and intentionally throw it into the atmosphere from orbit... and it wouldn't hurt anybody.

So whence comes all the hazard? Dangerous radiation is produced two ways, first during the process of splitting the Uranium or Plutonium atoms: gamma, X-Ray, and neutron radiations are released while the reaction occurs, but this stops when the reactor is shut off. The second source is the real problem, that while Uranium and Plutonium's radiation is a non-issue, the atoms they split into are different. This is the real hazard, that these waste products are extremely radioactive, and persist even if you shut the reactor down. Since these waste products are extremely radioactive, thousands and millions of times more than the original fuel, it is a scientific fact that they will not be radioactive for very long.

These waste substances are not stable, which is why they are so radioactive, and they will all decay and break down to safe compounds in the space of a few decades to a hundred years or so. Therefore, so long as it can be guaranteed that a spent reactor will not encounter the Earth in this time frame, there is no danger. The entire premise about nuclear waste being this eternal boogeyman is an environmentalist lie. Give waste a century or two to decay, and it will not be a problem anymore.

There are cases of Saturn V stages also entering solar orbit and reutrning

Yes, within a few million miles, in their orbit around the Sun! And thats for Earth-Moon rockets, not Earth-Mars rockets that will be going much further away. We are good enough at predicting the pathes of spent stages to ensure beyond any doubt that it will not hit the Earth during the time needed for the waste particles to decay.

The easiest way to get ride of any risk is not to take it.

Ah, the mission statement of the anti-rational, anti-scientific, anti-human precautionary principle.

So did Chernobyl and Hiroshima and Nagasaki beforehand

...None of which were harmed one iota by the fresh nuclear fuel. The entire fallout from  was due to the waste generated by the breakdown of the fuel, and the neutron bombardment of the area during the reaction. Also, both these Japanese cities are inhabitable today, probably Chernobyl too with concerted cleanup, 50 years following the  bombings. We can make sure no spent reactors fall within hundreds of years easily.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#84 2006-09-02 21:31:59

GCNRevenger
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From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: Ares and Ares

Oh, and about Galileo and Cassini, the notion that they were crash-landed to protect the moons/rings from the Pu238 fueled RTGs is absurd. Jupiter's main moons are utterly bathed in radiation thanks to the massive magnetic field capturing ionizing particle radiation. The capsules and fuel element composition ensure that it would never spread  if it did crash, and even if it did Pu238 is a whimpy Alpha radiation emitter. Plus its only radioactive for a couple of hundred years, which is nothing on any kind of time scale microbial life evolves over.

They just did that to appease the wailing man-hating environmentalists, at least indirectly.

Also note that real reactors, as opposed to RTG "nuclear batteries," would use Uranium 235 or Plutonium 239, and not Plutonium 238 which is a different kind of Plutonium. Full fledged nuclear reactors with fresh Uranium are far, far less dangerous than the RTGs we've been shooting into space for decades, even to the Martian surface (abord Viking).


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#85 2006-09-03 00:23:10

RobertDyck
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From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,935
Website

Re: Ares and Ares

The two practical nuclear fuels, Uranium 235 and Plutonium 239, have extremely extremely long longevities. Note that these are not Plutonum 238 nor Uranium 233 and 238 which are not nuclear fission fuel and have much shorter longevities.

I agree with most of what you said, but have to point out a mistake. It's true practical fuels are Uranium 235 and Plutonium 239, but it's not true that Uranium 233 is not fissionable. U-233 will fission, in fact it has a slightly shorter half-life than U-235 and slightly smaller critical mass. The shorter half-life doesn't increase radioactivity a lot, but it is fissionable. The reason it isn't used as fuel is that it has to be made from thorium 232. The reactor that makes U-233 from Th-232 will consume U-233 faster than it's made. Well, you can't consume something unless it's there so it will reach a low equilibrium with thorium and not rise above that. You could expose Th-232 to radiation from a U-235 reactor, but why? You can also expose U-238 to radiation, which forms Plutonium 239. Since 99.2745% by weight of uranium is U-238, processing uranium for U-235 will produce U-238 as a by-product. Since you have it anyway, you might as well use that for fuel. And plutonium produces more energy than either U-235 or U-233 and has a smaller critical mass than either. So as long as you have a source of U-235, either that or Pu-239 are practical fuels. If you have abundant thorium and a shortage of uranium, then any reactor design will consume U-233 as it's produced. I know, a picky detail, but accuracy is necessary. It would be more accurate to say U-234 is not a fission fuel, because it isn't fissionable and only 0.0055% of naturally occurring uranium is U-234. Everything else you said is true.

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#86 2006-09-03 05:40:34

GCNRevenger
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Posts: 6,056

Re: Ares and Ares

Frankly I left out U-233 because it isn't used as a fuel, not because you can't.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#87 2006-09-03 20:42:48

Martin_Tristar
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From: Earth, Region : Australia
Registered: 2004-12-07
Posts: 305

Re: Ares and Ares

All the technologies to date about nuclear propulsion 1950's - to today (including the NERVA) are based on the either combustion system and heating the propellant through a nuclear reactor or the explosive power of fusion bomblets exploding using shockwave for thrust. We need to look beyond the simple explosive engine systems and look for a quantum leap of tehnologies into the realm of hyperspace / hyper veolcity drive systems. There is a difference between Intra-solar system  missions and Interstellar Missions outside our solar system to beyond.

The development of Plasma drive and Ion Drive are the best hopes for Intra-solar system missions where the development of Hyperspace and Hypervolicty Drive is the best hope for interstellar missions.  Nuclear Reactors will be required to power the drive systems and onboard electrical systems but not drive the vessels in space.  So lets development the intra-solar system vehicles before thinking about the interstellar vehicles.

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#88 2006-09-03 21:52:18

RedStreak
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Registered: 2006-05-12
Posts: 541

Re: Ares and Ares

The easiest way to get ride of any risk is not to take it.

Ah, the mission statement of the anti-rational, anti-scientific, anti-human precautionary principle.

As much as I enjoy hearing another person's POV I am hardly anti-rational and anti-scientific.  If I truly were any of those things I'd be taking this commentairy personally and demanding an appology, but I am not.

Keeping this topic related to Ares and not nuclear-anti-nuke propoganda, Zuberin nuclear engineer or not intended it as a side-option.  If the nuclear stage were a requirement for the upcoming Ares in the VSE I fear it'd delay the project.

If I had to chose what might make a better alternative to nuclear propulsion initially I'd vote for ion propulsion but it is almost as notoriously slow as a solar sail.  Something like a plasma drive, which would give off exhaust not unlike a nuclear rocket minus the plutonium and radiation, might make a good compromise as long as it offers strong thrust that can be maintaned over a solid period of time.

Has anyone given thought to what might be required of the CaCLV's EDS?  Would it be as large as the Saturn V third stage or about the same as a Centaur stage?

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#89 2006-09-03 23:06:04

Tom Kalbfus
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Posts: 4,401

Re: Ares and Ares

All the technologies to date about nuclear propulsion 1950's - to today (including the NERVA) are based on the either combustion system and heating the propellant through a nuclear reactor or the explosive power of fusion bomblets exploding using shockwave for thrust. We need to look beyond the simple explosive engine systems and look for a quantum leap of tehnologies into the realm of hyperspace / hyper veolcity drive systems. There is a difference between Intra-solar system  missions and Interstellar Missions outside our solar system to beyond.

The development of Plasma drive and Ion Drive are the best hopes for Intra-solar system missions where the development of Hyperspace and Hypervolicty Drive is the best hope for interstellar missions.  Nuclear Reactors will be required to power the drive systems and onboard electrical systems but not drive the vessels in space.  So lets development the intra-solar system vehicles before thinking about the interstellar vehicles.

You know, if we could develop FTL technology, I think time travel would be the more attractive option than interstellar travel. I mean, all we have to do is colonize a past Earth. A lot of people say that FTL means time travel, the only thing we don't know is what time travel means. If you could wormhole into the past and mine the past for minerals whose location you already know about, then what happens to the same mineral deposits you've already mined in the present? If the universe duplicates itself by this time travel, you could do this endlessly. Sounds an awlful lot like a free lunch to me. Perhaps but perhaps not. If FTL travel was possible by time travel was not, there would have to be an absolute now, time would have to tick the same for the entire universe somehow. There would have to be an instant that was the same for the whole universe all at once. I'm not sure that this is possible.

Maybe light speed is the limit after all. I think in retrospect this wouldn't be so bad. If you want to travel into interstellar space, you don't have to go all the way to the nearest stars. What is likely to be waiting for you if you make the journey anyway. Basically what it is is another Sun with more planets orbiting it. We'll have more planets to land on, more asteroids to mine and exploit and from that material we can build more space colonies. I don't know what the chances of life modifying an atmosphere so we could breath it, would be. If we create our own earthlike environments such as terraforming Mars or building space colonies, we can do that anywhere, not just in the vicintity of stars, but literally anywhere their is matter to build from and an energy source we can exploit. It could be a star, or it might be a brown dwarf or even a gas giant. if we have fusion it could even be a frozen comet.

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#90 2006-09-04 06:34:34

GCNRevenger
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Posts: 6,056

Re: Ares and Ares

Zubrin knows that MarsDirect won't work without the nuclear engine, but he also knows that a nuclear engine would be a political and some extent a logistical barrier to the project being approved, so he's lying about chemical engines doing the job. You just can't fit the crew, equipment, and so on in vehicles & rockets that small, of all engineering endeavours space is the one where things are cut as close to the bone as possible, and Zubrin went too far. It isn't an inherint flaw with the arcitecture, but rather a problem of degree, that Zubrin cut too many corners which puts MarsDirect beyond a threshold of practical.

An ion engine presents problems, that the best way to use such a thing would be to spiral your Mars ship to the upper limit of Earth orbit, just below escape velocity, then use chemical engines for the final push. Issues with this include the fuel used for said push boiling off during the slow acent, and that the ship would be bathed in the Van Allen belts for some time. The ion stage wouldn't be readily reuseable most likely due to the latter issue, and that you'd still need tonnes of ion drive fuel.

A plasma engine is so voracious in power consumption that you would absolutely need a nuclear reactor - a very advanced one - to really get a performance boost out of this type of drive. If you double your payload but need 40 tonnes of old low-efficiency reactor, you aren't getting anywhere.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#91 2006-09-04 07:19:28

RobS
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Posts: 1,701
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Re: Ares and Ares

Oh, and about Galileo and Cassini, the notion that they were crash-landed to protect the moons/rings from the Pu238 fueled RTGs is absurd. Jupiter's main moons are utterly bathed in radiation thanks to the massive magnetic field capturing ionizing particle radiation. The capsules and fuel element composition ensure that it would never spread if it did crash, and even if it did Pu238 is a whimpy Alpha radiation emitter. Plus its only radioactive for a couple of hundred years, which is nothing on any kind of time scale microbial life evolves over.

They just did that to appease the wailing man-hating environmentalists, at least indirectly.

What I remember reading was that Galileo was never sterilized to planetary protection standards, so it was burned up in Jupiter's atmosphere so it would never crash into Europa and possible seed it with microorganisms. Jupiter could have microorganisms as well; that is, if enough of them can avoid the vertical air currents in the atmosphere that would take them high or low enough to freeze or incinerate them. Burning up Galileo would probably protect Jupiter from terrestrial microorganisms, but wouldn't protect them from radioactives. To do that, they should have used a gravity assist to eject Galileo from the solar system.

                    -- RobS

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#92 2006-09-04 07:29:43

Tom Kalbfus
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Posts: 4,401

Re: Ares and Ares

I doubt radioactives would spend much time floating in Jupiter's atmosphere, and Jupiter is made out of hydrogen, an excelent shield from radioactivity. Most of that heavy stuff is going right to the bottom, probably is going to sink in an ocean of liquid metallic hydrogen, there is probably no substance better for blocking radiation than metalic hydrogen.

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#93 2006-09-04 11:20:47

GCNRevenger
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From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: Ares and Ares

Oh, and about Galileo and Cassini, the notion that they were crash-landed to protect the moons/rings from the Pu238 fueled RTGs is absurd. Jupiter's main moons are utterly bathed in radiation thanks to the massive magnetic field capturing ionizing particle radiation. The capsules and fuel element composition ensure that it would never spread if it did crash, and even if it did Pu238 is a whimpy Alpha radiation emitter. Plus its only radioactive for a couple of hundred years, which is nothing on any kind of time scale microbial life evolves over.

They just did that to appease the wailing man-hating environmentalists, at least indirectly.

What I remember reading was that Galileo was never sterilized to planetary protection standards, so it was burned up in Jupiter's atmosphere so it would never crash into Europa and possible seed it with microorganisms. Jupiter could have microorganisms as well; that is, if enough of them can avoid the vertical air currents in the atmosphere that would take them high or low enough to freeze or incinerate them. Burning up Galileo would probably protect Jupiter from terrestrial microorganisms, but wouldn't protect them from radioactives. To do that, they should have used a gravity assist to eject Galileo from the solar system.

Bingo. Not RTG fallout.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#94 2006-09-04 23:44:18

Martin_Tristar
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From: Earth, Region : Australia
Registered: 2004-12-07
Posts: 305

Re: Ares and Ares

GCNRevenger,

Space provides a unique environment for power system that normally couldn't do on earth. because of the gravity differences , temperature difference we could use tecnologies not common on earth.  We need to development power systems that could generate energy up to several megawatts without the use of solar for spacecrafts, I have an idea that doesn't use nuclear reactors neither. For larger space vessels will require nuclear energy --- probably fusion power but that's in the future.

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#95 2006-09-05 06:29:44

GCNRevenger
Member
From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: Ares and Ares

Well, in space you have exactly three ways to get power:

  • -Use energy transmitted from someplace else (solar power, beamed power)
    -Carry all your power (nuclear, fuel cell, battery)
    -Convert your momentum into power (magneto/electrodynamic)

If it doesn't fall under these three catagories, then its snake oil.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#96 2006-09-05 10:37:52

Mars_B4_Moon
Member
Registered: 2006-03-23
Posts: 9,776

Re: Ares and Ares

Chemical is good.

Some nice images:

http://www.nasa.gov/pdf/151420main_aresV_factsheet.pdf
http://www.astronautix.com/lvs/magnum.htm

other options?
http://forum.nasaspaceflight.com/forums … 5&start=76
http://forum.nasaspaceflight.com/forums … ntid=10222
http://forum.nasaspaceflight.com/forums … entid=9638
http://forum.nasaspaceflight.com/forums … ntid=10621
http://forum.nasaspaceflight.com/forums … ntid=10617
http://forum.nasaspaceflight.com/forums … ntid=10582
http://forum.nasaspaceflight.com/forums … ntid=10583  HLLV paths
http://forum.nasaspaceflight.com/forums … 5&start=61
http://forum.nasaspaceflight.com/forums … 25&start=1
http://forum.nasaspaceflight.com/forums … &start=121
http://forum.nasaspaceflight.com/forums … 37&start=1
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http://forum.nasaspaceflight.com/forums … ntid=10708 Missions
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From http://forum.nasaspaceflight.com/forums … 45&start=1
http://simcosmos.planetaclix.pt/


Space Vehicles: A History in Patents
http://www.dataviewbooks.com/sapcecover.jpg
http://www.dataviewbooks.com/space-a.jpg
http://www.dataviewbooks.com/space-b.jpg
http://www.dataviewbooks.com/space-c.jpg

Over 260 pages of spacecraft designs from US government patent documents.

http://forum.nasaspaceflight.com/forums … entid=6541
http://forum.nasaspaceflight.com/forums … 6&posts=52

The main differences between Doc Zub's Ares and NASA's Ares is that Zubrin would have backed the use of a somewhat risky nuclear powered mission to get Americans to Mars,
NASA is going to use a less risky chemical version to not to go to Mars but the Moon and mark the  anniversary of apollo however majority of our un-educated US public will be asking why are we watching re-runs,  didn't we see this moon tv episode before ? and like others have pointed out a huge some of money will be wasted on the Moon before we ever get near Mars.

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#97 2006-09-05 21:56:09

Robert M. Blevins
Banned
From: Seattle, Washington State, USA
Registered: 2005-05-04
Posts: 29
Website

Re: Ares and Ares

In my recent book, 'The 13th Day of Christmas,' NASA and the Canadian Space Agency combine forces to go to Mars. One of the components is a Magnum.

I agree...it's time to quit with this Moon crap and aim a bit higher! roll


Don't give up reaching for the stars...
just build yourself a bigger ladder.

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#98 2006-09-06 00:31:39

Tom Kalbfus
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Registered: 2006-08-16
Posts: 4,401

Re: Ares and Ares

Why go to the Moon? Why not? Going to Mars doesn't preclude going to the Moon. For one thing the launch window to the Moon is contiuously open, while the launch window to Mars appears only once every two years. What is NASA going to do on the off years when their is no opportunity to launch a mission to Mars. Well. the more Ares V boosters NASA orders, the cheaper the per unit cost of each booster is going to be. Anyway, why do all manned missions have to be targeted specifically for Mars? The objective should be to develop a transportation system that can be used for the inner solar system. Maybe one mission can be for the Moon, another for Mars, and a third for the asteroids. There are alot of near Earth asteroids that could be investigated, maybe some asteroid mining ideas could be tested.

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#99 2006-09-06 01:43:09

cIclops
Member
Registered: 2005-06-16
Posts: 3,230

Re: Ares and Ares

The main differences between Doc Zub's Ares and NASA's Ares is that Zubrin would have backed the use of a somewhat risky nuclear powered mission to get Americans to Mars,

Chemical rockets will be needed to lift a nuclear propulsion system off earth, so Ares V would be used anyway to launch a NTP (Nuclear Thermal Propulsion) based EDS. Note that NASA's current vision architecture as described in the ESAS includes NTP (Chapter 1, Figure eight). Furthermore NASA will produce a detailed Mars architecture next year, nuclear propulsion will surely be considered given its high ISP to save mass and reduce transit times. However, using NTP depends on the risk and cost of developing it. Note also that Prometheus Power and Propulsion is in the 2007 budget for 2007-2011, it's funded at $9m a year, enough to keep the technology alive. Nothing is excluding using NTP given the current Mars mission timescale that extends beyond 2020.


[color=darkred]Let's go to Mars and far beyond -  triple NASA's budget ![/color] [url=irc://freenode#space]  #space channel !! [/url] [url=http://www.youtube.com/user/c1cl0ps]   - videos !!![/url]

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#100 2006-09-06 01:47:01

Martin_Tristar
Member
From: Earth, Region : Australia
Registered: 2004-12-07
Posts: 305

Re: Ares and Ares

I agree with tom, we could build a viable Mars mission to the red planet without the endangerment of the existing human missions for the Moon , but provides evidence to the Public of the resolve to expand humanity into space.

We need to develop a modular approach to Mars, that could use the existing hardware of CEV to assembly a working outpost for humans on the surface of the red planet. We could launch Ares V rocket with a first stage ( about 80 tonnes ) of the mars vessel into orbit and a second Ares V bring the second and cargo stage ( another 60 tonnes ) for the Mars vessel and then linking them in orbit using a shuttle derived robotic arm on the first stage, we can dock remotely from the space station or on earth.

When the mission commences the first stage would move the vessel away from earth orbit towards Mars , once near completion the first stage separates and with thrusters places itself into a orbit that could be used for establishment of a larger space station or platform. ( over several missions we could supply many stages to eventually be linked into a space structure within or past earth - moon system orbit.)

The second stage provides the thrust to supply the cargo to Mars where its deposited on the surface providing the tools, shelter/s,  vehicles, equipment and other supplies for the Human missions to mars to commence.

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