Space race seems to be heating up again

Metakron, Billy T pwns you, so shut up about nuke launches from the Moon.

 

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Thanks for the moral support, but I did make an insignificant error* in my post: The warning time with an ICBM launch is only 40 minutes at the max, not the 80 I implied*. I knew that the orbital period of the lowest circular Earth orbit possible is about 90 minutes and that the the ICBM, being lower would be less so I quickly, without thought, said "80 minutes," but the ICBM needs to do only "half an orbit," or less depending on the locations of the launch point "C" and the target point "A."
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*technically it is not even an error as I said "less than 80 minutes" and 40 is less than 80.

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BTW, more on subject: Yesterday S.Korea announced that it will send a spaceship to orbit the moon. China has aready done this, India and Japan both will in about a year, so it is now a four way race with China clearly in the lead. The US economy is in such sad shape and there are so many higher priority demands upon on it, like paying for its "oil wars," stupid alcohol from corn project (projected to have cost the taxpayers 92 billion by 2012), tax relief for the rich, etc. that the US is probably effectively "out of the race" for more moon or greater developments, but was the first to get to the moon (with men). USSR was first to get there with machines, photographing the back side and naming most of the features there after dead Russians, etc..

 

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I glanced at my post with the math analysis again and did notice a slight algebraic error in the following:

"...Hence the energy ratio of Moon to ICBM launches is greater than:

(rSs - Rrs + RSs - RrS) / (rSs/3) = 3(1 - R/S + R/r -R/s) = 3 + R{(1/r) - (1/S) - (1/s)} ..."

The last (right side) algebraic reduction is not correct (the factor of 3 applies to all terms, not just the first). But as before the two negative terms are very small compared to the (R/r) term, so again the cost of the moon launch is essentially 3(1+R/r) OR MORE times greater, still falsely assuming that it could be done with rail guns only.

R/r still is 11/3 so the correct answer for the "only rail guns" system is:
3(1 + 11/3) = 14, not the 6.666 times more expensive previously stated.

Hence for a realistic launch with chemical rockets, MetaKorn's suggestion is at least 14 million times more expensive than an ICBM attack.

(I guess that is a "pwn," but my intention was and is just to correct nonsense.)

 

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Grow up.

 

Billy, I am not even going to try to figure out exactly how you screwed up your math, but most likely you have something backwards. The energy cost of leaving the moon is a little bit more than the cost of accelerating to 5000 mph. The energy cost of launching an ICBM is the energy cost of accelerating to 18,000 mph, plus accelerating against higher gravity, plus expending fuel to propel fuel. Even going with the ratio of the squares of these two velocities, it takes ten times the energy to launch an ICBM. It actually takes a lot more than that because of the increased fuel rate, friction with the atmosphere, and a heavier rocket to hold more fuel.

 

Go read a physics book.

 

Leaving the Moon, ... but here is what you fail to consider, the energy cost of getting the missile, and it's launchpad there in the first place!

It's simple, an Earth launched ICBM does not break free of the Earth's gravity, that's the BALLISTIC part. An ICBM and launcher sent to the Moon do, so you have to supply the extra energy to break two objects free from the Earths's gravity, then slow them, and land them on the Moon in a controlled landing, and then have enough fuel to send the Missile back.

Also, like Billy pointed out, what is the journey time for a missile launched from the Moon? (I'll give you a clue, DAYS) And as the Earth is a rotating target wrt the Moon, how convenient are your launch Windows? (er DAILY) Or are you going to launch from the Moon, go into Earth orbit, and then de-orbit over your target? (more energy and control required).

So, like I said, you got PWNED, noob. Go read a physics book.

 

Pow, right to the Moon....

I have to say the answer to "why" is, to explore is the nature of man. Why the moon? The moon base was part of the original space plan made by NASA and championed by a man named Motts Who did much for the program. Motts said that if we did not make a base on the moon or at the very least a space station that America would get bored with space and the moon "trip" would be just that a trip, not a journey.

We are way short of where Pres. Kennedy said we would be in his address to the nation regarding NASA and human space exploration. We should be getting ready to colonize Mars not make a moon base. I figure we are about 20 years behind were we should be.

Some of the main reasons we are now going to the moon.

1. we found ice. ice means water and water means we can stay on the moon with out the added cost of transporting it.

2. we found a substance known as HELIUM-3 which is the perfect fuel source: extremely potent, nonpolluting, with virtually no radioactive byproduct. So we now have water AND fuel. This reduces the cost in a massive way. and since HELIUM-3 makes all known fuel on earth seem weak it makes going to the moon a money maker rather then a money pit.

3. All other nations on Earth also know about H-3 so who ever gets there first has a huge hand up over everyone else. So think of H-3 as the new gold and the RUSH is on!

 

Pissing contest, lol

Even if it were possible, there would be some other obstacles such as debris in space.

I wonder if it would be possible to intercept the missile by detonating nukes in space, or creating minefields in space to protect from missiles.

What could china hope to achieve by doing this?

 

Well, no. At present, \(^3H\) is useless. It's not a fuel, it's a potential fuel for a fission process we don't have yet.

It's not 'extremely potent' either, to harvest it terrestrially to use a fuel source would consume more energy that it would produce.

So, to the Moon, where it is more abundant. Whoop de doop, a whopping 0.01 ppm. You'd have to mine a lot of Moon to get a little \(^3H\). That means a massive operation on the Moon, and that means a lot of chemical rockets taking equipment there. Anyone got any good numbers, to validate cost/benefit?

On non-polluting, well, only certain reactions, and sadly the one that takes the highest temperature to initiate. Easier combinations of tritium and deuterium isotopes release a neutron.

 

Easy. The Soviet 'Galosh' ABM solution does not attempt a precise intercept, because that is really hard to do (hence the mixed 'success' of the US GBI's and Aegis ABM solutions) but rather detonates a small nuke in the upper atmosphere to destroy an incoming missile. This is a very pragmatic approach, it is better to have a small nuke detonate in the upper atmosphere than a large one over Moscow.

The very same system could defend from missiles launched from the Moon, should Metakron ever become president of the USA and find a way to waste all that money. Of Course, with a few DAYS notice, rather than tens of minutes, the Galosh system would be even more effective!

 

Please accuse me of something that I actually did, Phlog. Earlier in this thread I did consider the energy cost of sending things to the moon. A Saturn V type of rocket can put roughly 1 percent of its own mass on the moon, soft-landing. China mass-produces heavy lifters, and in case you didn't notice, that program is paying for itself. What is the cost of a space program when you have positive cash flow? That's right, it's profit. When you can make a profit doing something it's a hell of a lot easier. We're starting to see the possibility that China can put 100,000 pounds at a time on the moon.

The plan is to actually hit the Earth's atmosphere at the speed that the projectile has built up. This is why I say make it spherical, coat it with enough ablatives to survive reentry, and let the rest of the missile burn away. The payload needs only to know when its acceleration returns to a value just above one Gee, and maybe they could get fancy and rig some kind altimeter. It's not going to skip around the atmosphere once it's deep enough to burn its shroud off.

The trip time makes it possible to adjust the targeting using very little in maneuvering fuel. The engines would have to be able to be throttled to be able to do both sides of the Earth, or the missiles would have to be launched at different times. One of the benefits of the scheme is that the missiles could use cheap stable chemicals for propellants instead of cryogenics, just like the lunar lander. The engines would be a lot cheaper because they wouldn't need to produce as much thrust.

I don't know that radar could detect these incoming missiles even if their stealth technology was of the least advanced type. Put a sharp nose on them and as long as they are pointed directly at Earth their radar profiles will be nearly nonexistent. All of the surfaces of the missile would reflect the radar signals other directions. I seriously doubt that we can detect the launch of a rocket from the moon when the whole rocket is smaller than the return vehicle from the Apollo missions. Even that flash of light against a dark background isn't that easy to detect. As long as no one spills the beans the first notice we will have will be the actual entry into the atmosphere, and we won't be certain until our eyeballs have already been burned out of our heads.

 

The other thing that some of us don't want to think about is that the Chinese can use a position like that to harass shipping. Much smaller missiles can destroy spaceships and those can simply be stood up somewhere and launched. Even on Earth a missile could potentially be launched from a built-in stand. Even maneuvering out of the way of a missile would cost a lot of fuel.

Colonies on the Moon and elsewhere will eventually become self-sustaining. There are a lot of ways to get volatiles.

 

H3 recap of cost/benefit

FIRST OFF>>>

The Artemis Project is whats the US has dubbed the power plant for H3. H3 is required for a fusion reactant not fission. Helium-3 itself is non-radioactive. The lone high-energy proton produced can be contained using electric and magnetic fields, which results in direct electricity generation.

Reactors that exploit the fusion of deuterium and tritium release 80 percent of their energy in the form of radioactive neutrons, which exponentially increase production and safety costs, states Gerald Kulcinski, Director of the Fusion Technology Institute (FTI) at the University of Wisconsin at Madison. A nuclear reactor based on the fusion of helium 3 and deuterium, which has a single nuclear proton and neutron, would produce very few neutrons -- about 1 percent of the number generated by the deuterium-tritium reaction. "You could safely build a helium 3 plant in the middle of a big city," Kulcinski said.

About 25 tonnes of He3 would power the United States for 1 year at our current rate of energy consumption. To put it in perspective: that's about the weight of a fully loaded railroad box car, or a maximum Space Shuttle payload.


The current value of pure gold as of today is around $25,500 per kilogram. H3 energy value in today's dollars is around $5.7 million per kilogram when compared to the value and energy potential of oil. At $40,000 to $60,000 per kilo for transporting materials from Earth to the Moon, it is not cost effective to go to the Moon even for pure gold, at today's price of <$25,500 per kilogram. He3 equivalent energy value in today’s dollars is $5.7 Million per kilogram making this venture for the He3 fusion reactant worth the effort and cost.

Just one years production of H3 is equal to about 10 to 30 times the energy we could get from mining all the fossil fuels on Earth, { depending on the information source you look at} without the smog and acid rain. If we torched all our uranium in liquid metal fast breeder reactors, we could generate about half this much energy, and have some interesting times storing the waste.

In the end this Project {if it works out } would make more then 300 billion a year and stop us from using our resources here on earth as fast as we now consume them.


Reference: Kulcinksi, Cameron, Santarius, Sviatoslavsky, and Wittenberg, "Fusion Energy from the Moon for the 21st Century." 1988. Fusion Technology Institute, University of Wisconsin.Wikipedia. Guy Cramer 2004.

 

We are talking about 40 year old technology when we are talking about the moon rockets, too. Once again, the Saturn V is man-rated, so its stuff weighs more, and the electronics from the 1960s are a nontrivial burden. Any payload percentage that they could do in 1969 we should be able to beat by quite a bit these days.

 

Hey Flint, a cut and paste that does not address my points is not productive in debate.

\(^3H\) is hard to obtain. It is not viable to obtain it terrestrially, and you have not shown that harvesting it from the Moon makes economic sense.

You do not seem to understand that the reactions that produce NEUTRONS make the containment vessel RADIOACTIVE. Protons can be trapped, sure, but not all Tritium reactions produce just protons.

So, do the maths, show me how much it would cost to get that 25tonnes of \(^3H\) back to the USA to use as fuel. Oh, and figure in the R&D costs of developing the plant, and building it please.

 

We can't even make a biosphere work on Earth.

 

They'll do fine.

 

We can't even make a Biosphere work on Earth. They will never be self sufficient.

 

They'll do fine.