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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?"
Space Elevator. Everything else is too dangerous and expensive.
Now, I'm no rocket scientist, but I think you get the idea..
If you can read this sig - the bitch fell off.
One of the biggest problems with anything Nulcear, be it power, subs, or rockets, there is a very negative public perception. You can tell people that it is safe all you want but there will always be that paranoia. It doesn't help that people don't neccesarily trust the government.
"Is derriere REALLY that f'ing difficult to spell?"
Is fucking really that fucking difficult to spell?
"Derp de derp."
on Gas Core Nuclear Rockets
those have been around for years, and i have been fortunate enough to work with them for much of my life. they are called bean burritos. there is more explosive energy in one of those bad boys than most realize, especially when the chemistry behind the force is just right...granted, the fallout is pretty terrible too...
xao
http://TheHillforum.hopto.org
A few years back, I remember there being some amazingly loud protests from some anti-nuclear power folks about the dangers of a deep space probe going up with a nuclear power source. Those folks were worried about the danger if the rocket blew up on the pad or the 1 in 100,000 or so chance the probe would hit the earth on one of its acceleration orbits.
Just imagine how happy these folks will be with a nuclear powered rocket, even if the scientific community claims that they are safe. After all, it's nuclear related, so it's gotta be bad!! (tongue firmly in cheek)
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.
(article text, minus pictures)
Opening the Next Frontier
by Anthony Tate
Part 1: The Frontier Spirit
America loves its legends. George Washington in Valley Forge. The Wild West. World War II. The Man on the Moon.
But lately, it seems the legends have stopped.
Sure, we have the Internet to play with now, and computers are changing the world in ways we can scarcely grasp as of yet. The Soviet Union is no more, and despite our current travails with terrorism, a certain comfortable familiarity has us in its grip.
Where is the next legend? Where is the next frontier? Or are we just going to go comfortably off into retirement?
If the 'entertainments' of the kids these days are any indication, no way.
Extreme sports, fun little things like 'base jumping' and other diversions indicate that the next generation of Americans are harkening back to their roots in a big way. America is ready for the next challenge, refreshed, revitalized, and shaking off old fears and inhibitions.
But what could have caused our recent doldrums?
Why have we not gone back to deep space, that logical 'Final Frontier,' for so many years after Apollo? I believe it was a confluence of several factors, most of which have now passed, that caused us to huddle close to the bosom of Mother Earth for these past decades.
Part 2: What went wrong.
To be blunt, it was the 70's.
After the turbulent change of the 60's, the 70's were just a hard time for America. The Cold War dragged on and on, no end in sight. Vietnam was a horrible, bloody mess, deeply misunderstood to this day, and bitterly divisive even in the aftermath. Watergate destroyed the faith of millions in their own government. The Oil Embargo shocked the economy as well, causing the nightmarish condition of 'stagflation.' Cultural upheaval became the norm as gains in civil rights were cemented into place.
With that litany of bad news, there is little wonder that the public lost interest in space. When you are scared for your job, your children, and whether or not your paycheck next year will still cover the rent, idealism and exploration goes out the window.
Also, lets be honest, landing on the Moon in the 1960's was an incredible feat. That entire rocket, the whole plan, was designed, built, and flown using less computing power than you have in your PC. Genius level effort was used to make that program possible, and the chance of disaster was perilously high, even by the comparatively relaxed standards of the day. In other words, Saturn was ahead of its time, by many years.
If it wasn't for the Cold War imperative to beat the Soviets, we'd probably be looking to go to the Moon right about now, all things considered.
Add in the fact that science itself was throwing up massive roadblocks, and there is little surprise to be had from the seeming 'retreat from space.' The rocket fuel used in the Saturn V moon rocket at launch was BETTER than the rocket fuel used to launch the Space Shuttle today. Why is that? Well, it's simple: The chemical fuels used in the Saturn V are among the best fuels that chemistry allows. Science is remarkably inflexible: unlike in the movies we can't just 'whip up' better rocket fuels. Chemistry is pretty stubborn that way.
So, exploring further in space was not important to the country while we had other problems to deal with, and making rockets better than the SaturnV was pretty much impossible.
So, NASA went sideways for a while. The Space Shuttle is a remarkable system, but it is at its core a compromise. So while it is good at many things, it is great at nothing. But nonetheless, the Space Shuttle kept America in space, and slowly we were building momentum to move forward once again away from the Earth.
Then Challenger blew up (and now we've lost Columbia and her crew as well).
Now, to the doughty folks who made Apollo fly, that disaster would have been a learning experience, and development would have continue
My understanding is that the clean nuclear propulsion systems presently under serious consideration don't provide a high enough thrust/weight ratio to actually lift a spacecraft off the surface of the Earth. Rather, their primary use would be for entirely space-born craft, which would be assembled in orbit and zip around the solar system without actually ever touching down anywhere.
This space unintentionally left unblank.
Quick, someone ban the sun.
And stop people from living in Denver or flying on planes or going skiing in the mountains.
And let's not forget xray machines, cathode ray tubes (TVs and computer monitors to you non-engineers).
And what about that deadly substance known as "granite" that releases radioactive radon?
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"?
You are being bombared with deadly radiation right now! Coming from the ground, objects in your home, and worst, from mankind's eternal nemesis, the Sun itself. Please flee your home screaming and head for your nearest all-lead fallout shelter!
We'll call you out when it's safe.
The enemies of Democracy are
But unfortunately, the space elevator will be so obscenely expensive in terms of resources and labour to get going in the first place that though amortized over a large number of launches, the cost would indeed be low... they probably won't be willing to wait that long to recover their costs, so launches that way would be even more expensive than the methods we use currently.
File under 'M' for 'Manic ranting'
To prevent any sealed radio active capsule from possibly breaking on impact with the ground a malfunctioning rocket will have a 50Meg hydrogen bomb on it to destroy all the pieces in the air
..."almost no radiation"...
Drat, it seems to be getting harder and harder to realize my life long ambition of being exposed to massive quantities of harmful radition that will be the key to unlocking my secret mutant powers.
Magnetoplasmadynamic was actually a word? And why didn't Piccard ever use it?
VASIMR (Variable Specific Impulse magnetoplasmadynamic Rocket)- And I though telecom had too many acrynoms.
A gas core nuclear reactor has a high ISP (meaning it's very efficient), but it does not have a particularly high thrust. That means it's great for cruising and orbital work, but it's not a launch engine like Orion could be.
Could inexpensive cruises to the moon happen within our lifetimes?"
No.
See, here's the problem:
Nothing is permitted any more without a "business case" being made for it. No document, no invention, no idea, no presentation is countenanced unless it has 20% annual growth and the accountants and the management committee sign off on it.
Since it is impossible to get a bureaucracy to sign off on anything, nothing is permitted at all.
Small businesses and entrepreneurs are starved for capital. Large businesses and management committees have substantial capital, but refuse to invest it. Therefore, there is no capital; or, if there is, it is usually totally inadequate.
Middle management has a perfect series of questions for ideas like this. There is nothing in the world easier than criticizing an idea. Questions like "what do we need that for?" and "yeah, but how do you know it will work?" or "how can you be sure that will sell?" These questions are asked as if an answer is expected. The questions are followed by the comments: "It'll never work," and "sounds expensive" and "why can't we just use $OTHER_IDEA?"
But no answer is expected. The people asking the questions simply want to see how well the "idea person" can ad lib and how many bullshit one-liners and jokes they can reply with. After the middle managers have been entertained, a cocktail party laugh will circle the room, and the idea person will be escorted out of the building and into obscurity as the five-foot-wide-asses return to their bean salads.
As long as this continues, the rate of invention and "innovation" will be reduced to unmeasurably small levels. No vision, idea or invention can surmount well-funded cynicism. Brilliant, well-educated people's minds are being wasted because they report to lying, cheat fuck, greed-driven managers.
Middle management routinely turns its back on paying customers and competition-less markets. How the fuck are they ever going to accept a new "unproven" idea?
They won't.
Business isn't willing to pay for products, innovation and careers, so we get brands, mortgage commercials and layoffs.
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.
Javascript + Nintendo DSi = DSiCade
"Could inexpensive cruises to the moon happen within our lifetimes?"
My hope is that advances in medicine will extend my life to 150+ years so I can see more of these things come to pass.
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
Cassini, if I recall right, was to go inward to Venus for a gravitational assist, then fly by Earth again for another boost before leaving for the outer solar system. Because the trajectory was only marginally possible to begin with, they had to come rather deep in the gravitational well -- only 200 or 300 miles above the top of the Earth's atmosphere.
During that flyby, Cassini was traveling well above Earth's escape velocity of 10 km/sec. I never saw anyone seriously claim that the plutonium would have remained contained in case of impact.
NASA's response to that point was, essentially, "We don't hit planets by mistake". That was good enough to avoid the various court orders and injunctions that were being cooked up, but it might not suffice today. A few months after the Cassini flyby, NASA (or JPL or Lockheed, depending on whom you ask) did hit a planet by mistake, when the mars probe impacted instead of aerobraking.
On the other hand, the protestors' argument that there was enough plutonium on board to kill half of the Earth's population, if properly distributed, is sheer alarmism. Almost every Slashdot reader generates weekly enough of a certain other substance to, if properly distributed, impregnate half of the Earth's population. Yet only a tiny fraction of children are descended from slashdotters.