I thought they had evidence of blowby and damage to the O-rings even before that flight. Is that not correct?
I didn’t think that was the case. I thought almost every new flight for the first 100 flights or so was doing some form of envelope expansion. Possibly not the orbiter itself, though. It could have been systems inside, or the MMU, the Canadarm, etc. Maybe that’s why they felt it was safe to send a teacher.
In other words, political decisions overriding engineering judgement. Typical.
Uh, you’re wrong. Challenger exploded in 1986, and the teacher selection process had been going on for quite some time before that, and Christa had been selected to fly NASA some time (I forget the exact date) in 1985.
There was evidence of blowby past the first O-ring on previous flights, yes - that’s what the redundant second one was for; to hold pressure for the remaining portion of the burn. The overall design was proven adequate for the temperature envelope it was designed and qualified for. The problem came when both O-rings became inelastic at low temps, allowing blowby past both.
Feynman’s book, btw, makes it clear that the committee’s USAF Gen. Donald Kutyna had pretty much smoked the problem out before the hearings even started, based on his knowledge of similar Titan IIIC failures. Feynman freely admitted that Kutyna used him as a front man as part of political face-saving on Kutyna’s part - as a space program outsider, Feynman was free to say what needed to be said without the blame game and other repercussions that an insider would have to deal with. Kutyna practically told Feynman to do the ice-water demo, he says, and if someone with Feynman’s ego was willing to say that, it had to be true.
tuckerfan, I meant, perhaps too cynically, that McAuliffe would have made a fine campaign surrogate for BHWB so soon after her flight, and that GHWB and Sununu doubtless knew it. My phrasing was clumsy, though.
The originaly design of the joint didn’t allow for any blow-through of propellant past the o-rings. It was later decided, because the damage wasn’t a “critical failure” that it was acceptable, and then this line of reasoning quickly went to measuring the allowable in terms of the amount of o-ring left; i.e. if the o-ring was 70% intact, they had a 233% “margin” (over complete degradation of the ring).
This totally ignored the fact that the o-ring wasn’t supposed to see any degredation, and in fact shouldn’t have been subjected to any blow-through. That they were seeing damage should have been a clue that the o-rings or the joint was not behaving as expected (in particular, that the o-rings lost the specified resilience at low temperatures) and should have been subject to an FMEA even if it wasn’t resulting in a catastrophic failure. That NASA and Thiokol did not do so (even after notification by engineers in both organizations) was a part of the push to make sure that design problems didn’t delay the Shuttle schedule or dispute the facade that the Shuttle was a flawless, well-developed and tested workhorse rather than a test platform pressed into service as NASA’s only manned launch platform.
Stranger
To return to subject of asteroid mining for a second, I found this site which provides the following interesting info:
The only problem is that such a wealth of commodities would actually make them pretty “worthless”, from a supply & demand standpoint. They’d still have their intrinsic worth as materials, of course, but they’d destroy the commodities exchange, so if you’re considering your payoff for such a venture to be in dollars, marks, or euros, you’re going to cut your own rope. Quoting out the value of the metals in today’s dollars doesn’t address the impact that enormous quanties would have on those markets.
In other words, in order to justify such a venture, you’d have to have plans to use the material for your own purposes, rather than sell them on the market, unless you are prepared to cartel them, as with DeBeers and the diamond market.
Stranger
Oh, I agree, and if you’ll scroll up to one of my earlier posts, you’ll see a hypothetical scenerio of just such a situation, wherein I admit that it’d depress the market to almost nothing as far as costs go. Thus making it impossible for you to recoup your investment, unless you planned to make your money back in other ways.
Nitpick: you’ve got your timelines wrong.
While I don’t know whether Bush was instrumental in choosing Christa McAuliffe, I do know that the Challenger exploded in early 1986 (it was the only thing on every TV is my Freshman dorm), the middle of Reagan’s second term, and too early for 1988 election season primaries. Perhaps a stunt for the congressional mid-terms, but not for Bush I’s presidential bid.
Whoops! Scrolled right by Tuckerfan’s earlier post. Sorry.
Aorry I didn’t address these earlier
Point taken. However, you’re going to spend a whole lot more time, IMO, figuring out how design an unmanned mission to move an asteroid than to figure out how to keep a guy alive while he sets everything up.
The Mars guys linked to JPL that I’ve talked with, the ones interested in the science end of things, would love to get a human up there to collect data, but they regard it as unsafe. As it was put in a lecture I attended a few years ago: You build a lander that looks around the landscape and see a hill you’d like to explore. So later you have to send a lander with a Rover that can reach it. The rover discovers a deep fissure of interest at the top of the hill but can;'t climb down. Soa later flight has to have a climbing rover, etc.
JPL has a two-year freeze policy: The technology for a flight is frozen two years before launch. Some criticized them for not using the successful 1996 Pathfinder balloon-bounce landing plan on the failed 1998 Mars Polar Lander. Unfortunately, it had been frozen before Pathfinder’s test flight even landed. The 2001 Odyssey technology was frozen in 1999, too soon to add Pathfinder landing gear, so its lander was scrapped. Thus, we don’t see an application of the successfully tested technology until 7 years after its success. Combine that with a scenario like the one in the previous paragraph, and progress slows to a crawl.
Asteroid mining, near or far, is going to be done most economically using humans, at least using forseeable technology.
And again, this rotating habitat is going to have to be tested somewhere close at hand before deployment on Cruithne or whatever other NEA you want to put it on.
That means a moon base, which means a space station with a centrifuge, which means a shuttle of one variety or another as I outlined earlier.
Good point.
Again, not according to those who would like to get their results in less than 3 decades. Don’t get me wrong, I love the JPL and unmanned craft. I have their MER screensaver on this very computer. But exploratory manned vehicles are being hailed, in this thread and elsewhere, as the only viable direction of the US space program because of their relatively cheaper cost. Just wait till one of them finds something profitable. People will be calling for the heads of those who obliterated the manned program in favor of a slow-as-molasses series of unmanned craft.
The other problem with that analysis is that it ignores the fact that we may already have supplies of these metals in the quantities we need at much lower cost.
For instance, it might be cheaper to simply dig into the mantle of the Earth for nickel and iron than to go out and drag an asteroid back.
True, but some of the rare Earth’s might be available in larger amounts in the asteroids than they are on Earth. Certainly, for getting plain old iron, there’s no point in it.
On the other hand, any mining activities on the planet have an environmental impact. You probably aren’t going to be doing any deep mantle boring while Greenpeace and Friends of Earth are around throwing injunction after injunction at you. Don’t underestimate the difficulty of retrieving materials just because they’re on the planet, either. For instance, several companies have worked for years on ways of recovering maganese nodules from the ocean floor. Despite the fact that they’re just sitting there, no one has come up with an economic way of collecting them, though it did make a good cover for Project Jennifer (to recover a wrecked Soviet Golf-class submarine).
But the real reason to go out there, and engage in mining and exploration is, well, 'cause it’s there. It never really made sense to sail to China…until a wealth of gold undreamed of by European kings was found (well, stolen) on the way. The results were something no one could have predicted; the end of monarchy, the rise of a dominant European merchant class, the colonization of the Americas and (arguably) the first real chance at democratic government since Greece. Of course, there was also the bad; the subjugation and virtual annihilation of the native peoples, overdevelpment and destruction of habitat, Brittany Spears, et cetera. But, on the whole, mankind is healther, lives longer, and has more intellectual wealth and freedom than before, and hopefully, the wisdom to manage future exploitation more ethically and measuredly (though, when we eat at the Mongol buffet, we sometimes doubt it.)
Stranger
Extracting platinum from somewhere in the asteroid belt is going to be, well, astronomically more difficult and expensive than harvesting manganese nodules from the deep ocean floor, or finding the Western Passage to the Indies, for that matter. I find it straining all credibility to imagine such a scheme would ever be even remotely worth the trouble unless a significant human presence were already there. But then you’ve got the chicken-and-egg problem of figuring out how and why such an enormous population of humans would happen to find themselves in the vicinity and in need of a mass of raw materials justifying such an mind-bogglingly gigantic project. Yeah, all these goodies are “out there” but they’re useless to anyone who isn’t also “out there” more-or-less permanently, and why in the blazes would they be?
Pretty much. Perhaps one day it will make sense to mine the asteroids, but that would be a LONG time from now. Certainly beyond any of our lifetimes. The scale of engineering we’re talking about is so far beyond what we are technically and economically capable of right now that it’s almost useless to talk about it. By the time we have the ability to do things like this, we have no idea what our real industrial needs will be.
The pace of advancement in space is glacial, and it’s not all just because it’s government. I’m as big a fan of space and private space flight as you’re going to find, but we can’t ignore the fact that space travel is enormously difficult, energy intensive, and dangerous. I’ve heard people make comparisons to air travel and how rapidly it advanced once people knew it could be done. But the difference is that people really could build airplanes in their garages. Once the basic engineering was understood, it kicked off a huge effort by thousands of people.
Space flight is not like that. Even in private industry it will take millions of dollars to build even simple sub-orbital shipe, and multi-year development efforts to expand the envelope. It just isn’t going to change quickly.
I hope to live long enough to perhaps get a ride in a rocket. I hope I live long enough to see us telescopically explore rocky planets around other stars with big interferometry telescopes in space. I hope to see a permanent moonbase, and maybe public orbital flight for big money. Maybe by the time I die we’ll have humans on Mars, and we will have bored down into the ocean on Europa.
Other than that, I don’t expect much more in my lifetime, and I’m 41 now. When things get this complex, it just takes a long time to go through the hardware generations required to see really spectacular changes. Add to that the long flight times to get out to the asteroids and outer planets, and we’re talking about maybe a decade per generation of hardware, at best. At that rate, we won’t be harvesting asteroids for a long, long time.
Yeah, but in just getting there, there’s benefits to the project. Spin off technologies, strange random discoveries that nobody ever predicted. Those things benefit all of us, not just the guys lucky enough to be floating around on the ISS.
Oh and Sam, I can’t find a cite at the moment, but someone did a costs breakdown on Rutan’s project. They found that if something like half the people who are currently signed up to fly on VirginGalactic actually do, that not only will VG be in the black, but they’ll be so far in the black that the next available seats on the VG will be selling for prices that the average person can afford. Of course, by that time Rutan will be building his orbital space planes.
I can remember people saying in the 1970s when Salvage 1 was on, that no one would be able to build their own spaceship, that it would be too expensive for anyone but governments to do. 30 years later, someone did. Rutan’s a smart cookie, and he was weeping when he talked about his plans for future exploration. Now, either he’s the best damn actor the world’s ever seen, or he’s so wrapped up in the idea of humanity setting foot permanently in space that he’ll do everything in his power to make it happen. Given that he’s got Paul Allen’s deep pockets behind him, my money’s on him doing it.
Hell, there were scientists on the eve of the Apollo 11 launch saying that we’d never be able to pull it off! Damned naysayers are just pissed because they quit the patent office and now have to work for a living.
I’m not sure what you’re arguing here. I never said that spaceflight was impossible, or that you couldn’t make a profit on it. I’ve been a fan of Rutan’s since the Varieze days. He IS a bleemin’ genius, and I give him good odds of creating some spectacular spacecraft.
My point is this: Even if we get a robust private space program, you STILL aren’t going to see asteroid mining in your lifetime. I’d be surprised if you see a private orbital ship by 2010, and maybe not by 2015. The first ‘space hotel’ might consist of a couple of transhab modules that you can fly up to and spend a night, and we might see those in a decade or two if we’re lucky.
As far as NASA goes, they’re barely planning on getting to the moon again by 2025. The CEV isn’t even supposed to fly until 2014. So NASA is out of this game. Their timelines are already drawn out for the next thirty years, and asteroid mining isn’t on the list. Hell, they recently scrapped the Jupiter Icy Moons Orbiter mission because they decided they couldn’t make the technology work in a 10-year timeframe.
Now think about all the technology we’d have to have in place to mine or move asteroids around. Think of how much power would be required. The technical challenges would be immense. Hell, they’ve got serious problems now with the Prometheus reactors, and those are like AA batteries compared to the scale we’re talking about. Then you need some way to move the things, we’d have to prove out all kinds of methods for doing heavy construction in space, we’d have to build and test the tools themselves, there would be many precursor missions to test out methods and technologies. And, before you go to the effort of mining these things you’d have to do a bunch of sample missions to ‘prospect’ them. The list goes on. This is orders of magnitude beyond anything we’re currently even contemplating doing in space.
I was a big space nut in the 1970’s, ad I remember all the breathless talk about how far we’d go by 2000. Remember space colonies? Gerark K. O’Neill thought we’d have 100,000 people living in space by 2000. I was too young then to understand just how insanely optimistic this was. Now that I understand more about how large-scale engineering works, I realize just how many devils lurk in the details.
Well, “because it’s there” is very romantic, but when projects start racking up price tags on the order of tens-of-billions, or even hundreds-of-billions of dollars, I think it behooves us to be wary of romanticism. The Moon shots were amazing technical achievements, but there’s little point in glossing over the propagandist rationale behind them, nor what is arguably their astounding lack of utility given the investment. I remain highly sceptical of the real benefits in “spinoff” technologies realized during the Apollo program, despite their being aggressively touted by admiring technophiles. As for science, there appears to anything but a consensus on the project’s overall worth, as wonderful as returning samples from the lunar surface unquestionably was. Anyway, I don’t want to open up that particular can of worms.
I’ve always most admired, for sheer bang-to-buck ratios, NASA’s and the JPL’s robotic missions, like Pioneer, Viking, Voyager, Galileo, Soujourner, Sprit&Opportunity, Cassini, Hubble, and so on. I suspect all of those put together cost less than the Apollo program (adjusting for inflation, etc.); maybe even less than the Shuttle program. The Shuttle Program especially has been such a disaster I have come to seriously doubt our government’s ability to responsibly implement and manage a manned space program. Perhaps it’s just not something government-run administrations should do. Robotic missions have clear scientific justifications and goals. What I am struck by over and over again is how our manned missions have been nothing if not projects in perpetual search of a clear justification for their vast expense. With this problem to tackle, enter the politicians, with their concern for such intagibles like “national prestige”, and pretty soon you’ve got…well, you’ve got the Shuttle. Perhaps their sheer delineatedness makes robotic missions intrinsically resistant to the kinds of rhetorical and bureaucratic madness that rendered boondoggles like the Shuttle, or the ISS.
Maybe missions with nothing but science objectives are the only projects NASA should be entrusted to embark on. Without a fundamentally, self-evidently sound reasons for going there, I predict more extravagance, waste, and pointless failure out of our manned space program, and if something fundamental about NASA and those who direct it doesn’t change, I suspect we’ll be having this debate over and over again for the forseable future.
Sam, you and I are old enough to remember what life was like before PCs became more common than toasters. The first home computer was introduced, IIRC, in 1974, but not too many people had them. Even when the Apple ][ was introduced, it was still basically a curiosity for most people. PCs didn’t start becoming commonplace until the 1990s, finally exploding in the late 1990s and turning into toasters (i.e. everywhere). What happened? The technology hit a critical mass, thanks, in part, to the internet. Now, suborbital flight seems to have hit a bit of a critical mass thanks to the X-Prize. After all, Rutan’s claimed the prize, so what’s the point in continuing? Plenty, judging by the partial list of folks you mentioned above. Now, we’ve got America’s Space Prize which aims to do the same thing for orbital flight that the X-Prize did for suborbital. We’ve gone from the Wright brothers at Kitty Hawk to “Lucky Lindy” in a couple of freakin’ years. It took decades to get aircraft that far. How many people would have predicted in 1974 that we’d have the kind of computer networks that we’ve got now? How many more people would have believed those predictions?
Yeah, engineering a spaceship is a helluvalot more complex than engineering a PC, but remember, the hard part is figuring out how to do it the first time. Once you do that, anyone with the tools, the money, and the desire can do it. Rutan’s not only got all three, but he’s got more brains than half the folks at NASA. For me to say it can’t be done, means I think I’m smarter than Rutan, and I ain’t going there.
Loopydude, I never said I was putting my money on NASA. Rutan himself said that they either need to get their act together or get the hell out of his way. I’m betting that Rutan’s gonna run all over them.
Then we are probably in full agreement. I’m mighty gung-ho about these aerospace entrepreneurs. For one thing, they’re not wasting my money.