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Clean Nuclear Launches?
AKAImBatman writes "When it comes to launching millions of pounds of material into space, nearly everyone knows about the Orion Project. Blow up a series of nuclear bombs under your dairy-aire and ride the explosion on up. Unfortunately, the Orion spewed out so much radiation that it just wasn't a feasible launch option. If we want commuter trips to space, we're going to have to find another way. Well, it turns out that NASA's been doing quite a bit of research on Gas Core Nuclear Rockets, an ultra-powerful nuclear rocket that puts out almost no radiation. This research has spurred a fascinating new generation of ideas on reaching the cosmos. Could inexpensive cruises to the moon happen within our lifetimes?"
Could inexpensive cruises to the moon happen within our lifetimes?
I highly doubt it. As the last twenty years have shown, it's not the level of technology that determines how easily we get into space, it's the cost. And concepts such as these, while interesting to think about and develop, are ultimately going to take that many more decades to become proven.
Add to all this that the public would need a near-100% safety record in order to buy into a space tourism industry, and we're looking at more decades added onto the R&D and testing.
However, this kind of engine if developed properly COULD lower costs for putting satellites in orbit. So what's our benefit in the end? Lower satellite TV, telephone, and internet costs perhaps... But that's being optomistic.
But the design itself? Neat.
The environmental whackos go nuts (and let slip the lawyers of war) when you launch a totally sealed reactor, can you imagine what they would do if you wanted to launch something that *gasp* released radioactive gasses into the atmosphere?
Why is it that the proponents of "one nation under God" are so eager to get rid of "liberty and justice for all"?
There's a genuine safety issue with space elevators that ought to mentioned though, which is that if the elevator breaks, the part between Earth and the break point would act as a whip. A few thousand miles probably wouldn't be a big issue, but the closer to the end the cable breaks, the bigger, exponentially, the whiplash. A shockwave that destroys significant amounts of life on Earth isn't impossible.
You are not alone. This is not normal. None of this is normal.
Where the reaction begins has no bearing on the danger the reactor poses; again, it's an education issue.
The danger in the event of catastrophic failure comes solely from a possible dispersal of the fissile material.
We have reactor designs now that simply can not result in the reaction going critical. It'd actually be much safer now than it was in the 70s.
The only reason you're not allowed to talk about these things, even to educate the public, is the same reason you're not allowed to promote nuclear power generation. It's simply career suicide for any public official to broach the subject.
Provided the radiation from their rocket stays at what the specs suggest, this is no more inherently dangerous than the operation of any of the dozens of nuclear reactors currently commissioned in the united states. (not counting nuclear naval craft)
The public's irrational fear of all things nuclear is the only opponent that killed nuclear technology. It has nothing to do with actual science or statistical risk.
// "Can't clowns and pirates just -try- to get along?"
You're quite wrong. :-) The Orion was originally intended for launches from some remote area. The nuclear pulsing could blast just about any weight into orbit, then take that same weight around the solar system. When various treaties banned the use of nuclear weapons on the ground, Orion switched to space only mode. Then they banned space-based bombs and Orion became a dead-duck.
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The space elevator needs equal pull on both sides of the point where it would be at the same distance from Earth as objects in geosynchronous orbit. You can either do that using a counterwieght such as a large asteroid, or by making the elevator exceedingly long, about the same length on either side of that geosync orbit position.
Admittedly, the basic ground-to-counterweight-above-sync-orbit design has great potential. But there are other designs with less cost, extreme materials, and risk.
For instance: A section of cable in low orbit, spinning end-over-end so that each end periodically dips into the stratosphere at approximately the average local wind speed. Fly up to it, hook on as it goes by, and get lifted into orbit. Balance the momentum by bringing back a payload of space-mined material on the other end.
Build it so that if the orbit decays it will break up on reentry rather than crashing, keeping its own mass low enough that it won't create another Cretaceous event by spreading tons of red-hot debris throught the upper atmosphere if it comes in. (But if you get your spin right you can design it so that it tends to be pushed UP if the active guidance fails.)
Use a near-circular orbit if you want to lift a lot of payloads to near orbit (where you can use slower engines - like ion or light-sail - to achieve high orbit or escape), or an eliptical orbit for fewer payloads to a higher initial launch.
Lots of ways to do the active guidance:
- Control the spin with currents through the cable to electron guns and collectors at the ends working against the earth's mag field.
- Small attached light sails - For orbital elements, spin, attitude, AND killing vibrations.
- Ion thrusters ditto - and you can collect reaction mass each time an end dips into the atmosphere.
- Control, solar power plant, etc. at the center, which never enters the atmosphere. (Elevator/cable-crawler to get there from the ends.)
Lots of other systems are possible, too.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Actually, a SE makes a significantly better, safer and cheaper inter-solar-system-transportaion-system than dirty bombs. It's not just a tool to escape orbit - it can take us to other planets. That's what's so genious about the idea.
There are two reasons for making it 91000km long when all you technically need is 35000km.
One: because you need a very large and unfeasible mass at the top if you want to balance 35000km of cable hanging below GEO with a weight located, say, 1 meter above it. You need a significantly smaller weight at the top if you want to balance it at 91000km.
Two: (which brings us back to our point of discussion) If you go as far as 91000km, you can slingshot payloads as far as jupiter and its moons. If you build even higher, at 140000km you can get as far as pluto.
Of course, the first thing you'd want to send to your destination is a pre-fabricated and spooled SE to deploy there, so you can send stuff back...
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The kind of stuff we have to deal with from nuclear power plants is nasty. WAY nastier than anything which comes out of a traditional power plant.
Which is why we have to figure out how to get the stuff into space cheaply so we can jettison it into the sun. No geology to think about. No tectonics or water flow, just pure fusion energy cooking the bejesus out of our toxic waste.
"Not to mention the fact that your average coal burning plant simply doesn't have the potential to cause a catastrophe on the scale of Chernobyl"
Not all at once in one place.
Coal and Petrochemical based air pollution has killed tens of thousands to hundreds of thousands at younger ages than they would have otherwise died, and cars and tobacco have killed TENS OF MILLIONS of people this century, and yet you think that the HUNDREDS of reactors in current operation in North America whom haven't killed a SINGLE HUMAN BEING yet - are a bigger badder threat.
Stupid dumb public. And they bitch like hell when we try and keep their asses in High School all the way through until grade 12.
Actually, going critical and melt-down are two different, yet slightly related events.
"going" critical: All nuclear reactions (not nuclear decay) are critical. In order for a self sustaing nuclear to occur, a critical mass of fissible material must be present. If the mass falls below critical the reaction will extinguish. Decay will still occur and generate heat, abliet much less.
Melt-down: A melt-down happens when a reaction goes out of control and produces sufficient amounts of heat to cause the core the liquify (melt down). When a core melt-down happens, there is not a damn thing on this planet (that I know of) that can the molten (and getting hotter by the second) glob that used to be the core.
It has been theorized that if this happens, the molten core will burn through the earth until it reaches water. Upon contact with the core the water will turn into steam and create what is in effect a steam cannon, blasing the core back up the hole and showering bits of the core for miles around.
Sometimes. Sometimes not. On my college campus there was a small (6 MW IIRC) nuclear reactor, used for instruction in the Nuclear Engineering courses. I took a tour of it once (I was in Chem E, not Nuc. E, so I never got to do any actual work with it) and heard an interesting story from one of the professors there.
They were doing a scheduled test one weekend of some of the safety systems, so they were expecting some alarms going off. One of the students walked in the door, and suddenly all of the radiation alarms went off. They got out their gear and traced it down to the student who had just walked in. Specifically, they tracked it down to his head. So they got a 55 gallon drum of water and started washing his head. After a little bit of that, the water was radioactive, but his head wasn't. After they were finished, he told them what he had done. He had gone to WalMart and bought a wick for a coleman propane lantern. He took some scisors and cut it up into fine pieces, and sprinkled it on his head (The wicks are coated with a chemical which gives it a cleaner, whiter light, and also happens to be slightly radioactive).
The amusing thing about all of this is the contrast between normal use and a nuclear power plant. 99.99999% of the coleman wicks that are sold are thrown away in the trash (or littered with near campsites) because they really are not a hazard to anyone, and no sane person would say they are. However, because he brought the one he bought into a nuclear power plant, the plant had to classify the whole 55 gallons of water as potentially dangerous nuclear waste, and they had to spend a fairly large amount of money to have it disposed of "properly". How much of the nuclear waste that's being encased in concrete and buried under miles of rock is more (or less) dangerous than what you can buy in the local WalMart?
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