Unless space elevators make it, and make it in a really big way, I can't really see that happening; the environmental cost of launching every man, woman and child off of the earth is rather prohibitive.
Atleast I assume you are talking about moving them, and not doing something more drastic;-).
The prize money is just at $5 million, so to make it economically viable to enter this competition your vehicle must be developed for less than that...
Nope. The teams intend to sell flights to the general public. I mean, that's what the prize is trying to encourage, right? So they can borrow/invest money as well towards their expected income.
However I just can't ignore the incredible amount of resources this 'fun' is going to cost
No.
The fuel cost is very, very low actually; less than $10/lb of payload.
I worked out that if I was to go into space, I'd have to spend about as much fuel putting me there, as my car burns in a year. But unlike my car I ain't doing this every week or even every year. The number of people going into space for the forseeable future is only a few thousand; the number of cars out there are incredibly high, in the hundreds of millions, so the relative environmental impact of rocketry is quite, quite negligible.
And there are plenty of space technologies that have a positive environmental impact. Would the ozone layer hole have been found without satellites? I actually believe that overall, space will have a very significant net positive environmental impact.
I've been running a Naive Bayesian filter for about 3 weeks now, and it's misclassified NO good email as spam, but it has marked about 10% of the spam as normal mail. As I understand it, my experience is entirely typical.
You still have to eyeball the subjects of the spam messages just in case, but the fact that you don't have to manually delete them is a very good thing- it does save quite a bit of time that they are already sorted; and as I said it hasn't fucked up once so far in that sense.
Also, I spend almost no time dealing with any filters. Once a week I take the pile of spam that it missed and tell it that it was in fact spam; it takes about 2 minutes and any similar spam will get spotted in future.
It's definitely a far more pleasant way to deal with the issue, and it does save time. It seems to be almost as good a scheme as any so far, and at the moment it looks unlikely that any scheme will outperform it by much; so it may well be 'good enough'.
For solar system exploration, tho, LOX-liquid hydrogen is king for two reasons. One, it IS the lowest mass alternative when it's done right, and on planetary missions "lowest possible weight" is a BIG deal.
If you're worried about weight; then ion drives do much better (particularly Hall effect thrusters, ISP about 1500s). I think long term VASIMR is the way to go though (ISP 20000s); but its a waste of time right now IMHO.
Two, if you take along a small nuclear reactor to generate electricity for hydrolosis (sp?), you can refuel a LOX-liquid hydrogen engine anywhere in the solar system you can find water ice - the poles of the Moon or Mars, Europa, comets, lots of places. There ain't no kerosene out there.
That's not a small reactor that's a large one; and generating electricity is hard because getting rid of the waste heat is awkward in a vacuum. If you get off the Earth, the ISP needed goes down considerably. You should check out www.neofuel.com he talks about a nuclear/solar powered stean rocket, ISP is only about 190s but the system mass is orders of magnitude lower; you don't need such high ISP if you can refuel.
Yeah well, the fact that NASA didn't have an air reprocessing plant and would have had to spend more than a billion (plus overruns) designing one doesn't exactly inspire confidence that America could have gone it alone. The Russians had one from off the shelf they could use.
Don't forget the Russians have been in space continuously for 30 years. NASA haven't. There's plenty of things that the Russians have realised that NASA haven't (like it's a bad idea to toss liquids overboard in space cos it condenses and jams the docking ports).
And the Russians probably could have launched their entire section on one Energia if they had been allowed to. America has nothing that big.
The SSME burns liquid oxygen and liquid hydrogen which is MUCH more chemically efficient - you get LOTS more energy out of much LESS fuel. In fact, the liquid oxygen / liquid hydrogen combination, and the way the SSME burns it at an almost theoretically perfect specific impulse of 480 seconds, is the BEST chemical propulsion engine that is EVER going to be built.
The latest studies have show that for a first stage- LOX/Kerosene outperforms LOX/LH. There are lots of reasons for this:
a) the density of LH is really very poor indeed
b) (consequently) the thrust to weight ratio of LH engines is worse, kerosene gives much more thrust for the same weight
c) the weight of the vehicle goes down more slowly with LH, this increases 'gravity losses'
d) the density of Kerosene is very high
Anyway, bottom line is: LOX/Kero needs less delta-v than LOX/LH to get to orbit by about 6%. However, it doesn't give as much thrust per unit weight. But the density is 5x higher, which means that it is much easier to pack more fuel into the tanks to compensate. Once you realise that LH is more than 5x more expensive, and many, many times harder to handle then you start to seriously wonder why the Space Shuttle uses LH.
LH is good for upper stages though- the reduction in stage weight makes the lower stages smaller.
They will still be using SSMEs in Star Trek time - Scotty would sing their praises.
They may be good for deep space work. They're not as good as LOX/Kero for launching however.
No, my analysis has nothing to do with optimisation- all rockets are pretty highly optimised.
The issue is more to do with flight rate. Reusables are several times more expensive to design, and tend to have less payload, (everything else being equal, because they have to be stronger to survive being reused).
Therefore to make them cost effective you have to reuse them many times to recoup the extra investment.
The offset for this is that the cost of the hardware itself is amortised over each reuse. So if the hardware costs $10 million, then if you reuse it 100 times, it only costs $100,000 per launch. Likewise the development costs.
But typically most launchers only launch 5-10 times per year, so the flightrate isn't there right now- it would take 10 years to recoup the extra development cost, and then there is interest on top...
In contrast, a cheap expendable can be knocked out very cheaply, and at these launch rates it's a win to do that, alas.
While the Neanderthal / Cro-Magnon stuff is probably true (I was under the impression that the question had been decided years ago - they both were around at the same time, Neanderthals died out)
That is the working theory. However I am not aware of any proof; and I fail to see how a few thousand year old mummy in a glacier could have resolved a question about Neanderthals which died out tens of thousands of years ago.
Whatever this article implies, I'm pretty sure that no samples of Neanderthal DNA are known to science, so until we have some, the question seems open.
As an example, suppose all the white skinned people in the world were killed off [n.b. I'm not recommending this, I'm white!]. Would that mean that the remaining population were not descended from whites? Of course not. So the question is whether Neanderthals and human ancestors could interbreed. I don't know, and I don't think anyone has any evidence either way, but one thing is for sure, I bet they tried;-)
mmmm. More like $5000 per kg ballpark for cheap launch vehicles. (which is still much less than shuttle)
No. Russian Proton is about $2500/kg right now to LEO. Sea Launch is about the same. Ariane is nearer to Space Shuttle costs per kg, but that's a geosynchronous launcher whereas Shuttle can only make LEO.
My rule of thumb is that Geosynchronous is about 3x more expensive than LEO; since you need more than 3 the payload at LEO to be fuel for a kick motor to push you up the last bit into GEO (an additional 3.8 km/s).
No. You've missed the point really. The point isn't that Saturn V is cheaper, it was about mid-priced, it's that expendables, at todays launch rates, are cheaper.
The cheapest expendables designed use, strangely enough, ship-building skills. So the skills are out there, for constructing these vehicles.
That's not much more than the Space Shuttle; in fact the Space Shuttle is arguably more expensive. But the Saturn V payload to LEO was 100 tonnes compared to 25 tonnes that the space shuttle manages.
Yeah, well the reusable idea has been a resounding success. The vehicles are cheaper, less maintenance, quicker turnaround and totally reliable and are able to reach amazingly high orbits.
He, he he. Who am I kidding? Actually none of the above. Saturn V was actually 4x cheaper than the Shuttle per kg; and that was expendable. The Russian vehicles launch for about 1/20 of the cost of the Shuttle, and they're expendable.
Studies have shown that cheap expendables can cost as little as $500/kg, cf $20000/kg with the Shuttle.
And its not high tech, its the money stoopid, that is holding back Moon and Mars. We have the technology.
No, no, no. IQ tests doesn't measure intelligence at all. They measure your ability to perform well in IQ tests. It's just a number.
Actually that isn't entirely correct. The idea behind IQ tests was to predict who would do well in higher education, and hence who it is worth letting in. As that, it succeeds pretty well- the correlation coefficient between IQ and academic success is something like 60% IRC.
Extrapolating this index further to other areas works less well; I believe that high IQ scores correspond to only about a 5% increase in earnings. Probably other factors like so called 'EQ' correlate better with the other 'success' metrics.
The problem is that P2P is an inefficient use of bandwidth. Lots of traffic for little "gain".
P2P has been with us since the very earliest days of the internet. P2P is NOT inherently inefficient. However a lot of implementations of P2P are inherently inefficient.
Trust me, you do not want the ISP fiddling with your traffic in some nefarious way in their network.
On the one side, they're rocket engines, and they achieve maybe 97% of the theoretical maximum performance you can get from liquid hydrogen/liquid oxygen from these propellents. Cool!
On the other, they're expensive as hell, after 30 years of flying they're only just now looking like they're even close to getting them fully reusable (does it count if you have to remove them and tear them apart after each and every mission 'just to check'), and contrary to what NASA will tell you they aren't the only reusable engine out there (other engines aren't classed as such, mainly by NASA, but have had >2,000 seconds on them during testing, and that's about the same as most of the shuttle engines have, only the other engines probably need less maintenance.)
Oh yeah and they burn hydrogen. Hydrogen gives great exhaust velocity, but it's really seriously not very dense. This makes the tanks, fuel lines, and pumps much heavier, (that external tank costs $100 million, oh yeah and they throw it away each time).
Current thinking is that LOX/LH is about 6% worse overall than LOX/Kerosene for getting to orbit- the rocket needs more delta-v due to the extra vehicle weight and other technical issues and that swamps the extra performance of the hydrogen; oh yeah and LOX/Kerosene may not have needed an external tank to be thrown away because Kerosene is much denser.
All in all. Hey, it works! Anyway, pass the popcorn someone; it's still a rocket engine, and it makes a loud noise.;-)
You left out a;-) which makes me think you are worryingly serious.
No, it will be unfair on the rest of us. They'll come out of prison with huge debts, and have to commit more crimes to avoid going back in for lack of payment. Insurance premiums would go up massively; and the thieves will get less money on the item once they have fenced it than the item is worth, so non criminals lose out all the more.
In the film Brazil, after your arrest you have to pay for your own interrogations, your stay in prison and so forth; they send you a bill afterwards for the Governmental services you 'used'; or if you don't survive the interogation, they present the bill to your next of kin.
Sounds to me like the Germans just sent the bill a bit early; they should have sent it after the investigation was complete.
So how do you convince someone to buy something without using words like "buy" "purchase" "special" "deal" "unique" etc? How do you convince people to come to your porn site without describing the pics you'll find there? Care to post an example spiel?
I don't know you from Adam; you may be a spammer for all I know, or a spammer may read this. Either would be bad. So no, I don't care to.
Um. As I understand it all of the manned Apollo missions went through the worst of the Van Allen belts- these belts are really nasty; the astronauts received about 1% of a lethal dose in the short time they traversed it; and they went through it twice; once on the way out, once on the way back.
Really? No. Not really. There's no way to know this was caused by him going into space. Lots of people get cancer anyway. The doctors or coroners sometimes say otherwise, but it's mostly just a best guess in nearly all cases, and it's frequently not terribly scientific.
Yes, maybe more, maybe less. What's wrong with that? Even if one of them dies of cancer we won't know whether that was caused by the radiation- there is no test for radiation induced cancer- cancer is cancer (pretty much.)
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What on earth do you think he's been doing all this time? Those aren't games- they're training simulators. ;-)
Atleast I assume you are talking about moving them, and not doing something more drastic ;-).
Nope. The teams intend to sell flights to the general public. I mean, that's what the prize is trying to encourage, right? So they can borrow/invest money as well towards their expected income.
No.
The fuel cost is very, very low actually; less than $10/lb of payload.
I worked out that if I was to go into space, I'd have to spend about as much fuel putting me there, as my car burns in a year. But unlike my car I ain't doing this every week or even every year. The number of people going into space for the forseeable future is only a few thousand; the number of cars out there are incredibly high, in the hundreds of millions, so the relative environmental impact of rocketry is quite, quite negligible.
And there are plenty of space technologies that have a positive environmental impact. Would the ozone layer hole have been found without satellites? I actually believe that overall, space will have a very significant net positive environmental impact.
You still have to eyeball the subjects of the spam messages just in case, but the fact that you don't have to manually delete them is a very good thing- it does save quite a bit of time that they are already sorted; and as I said it hasn't fucked up once so far in that sense.
Also, I spend almost no time dealing with any filters. Once a week I take the pile of spam that it missed and tell it that it was in fact spam; it takes about 2 minutes and any similar spam will get spotted in future.
It's definitely a far more pleasant way to deal with the issue, and it does save time. It seems to be almost as good a scheme as any so far, and at the moment it looks unlikely that any scheme will outperform it by much; so it may well be 'good enough'.
You can turn that off though; and I recommend you do that.
If you're worried about weight; then ion drives do much better (particularly Hall effect thrusters, ISP about 1500s). I think long term VASIMR is the way to go though (ISP 20000s); but its a waste of time right now IMHO.
Two, if you take along a small nuclear reactor to generate electricity for hydrolosis (sp?), you can refuel a LOX-liquid hydrogen engine anywhere in the solar system you can find water ice - the poles of the Moon or Mars, Europa, comets, lots of places. There ain't no kerosene out there.
That's not a small reactor that's a large one; and generating electricity is hard because getting rid of the waste heat is awkward in a vacuum. If you get off the Earth, the ISP needed goes down considerably. You should check out www.neofuel.com he talks about a nuclear/solar powered stean rocket, ISP is only about 190s but the system mass is orders of magnitude lower; you don't need such high ISP if you can refuel.
Yeah well, the fact that NASA didn't have an air reprocessing plant and would have had to spend more than a billion (plus overruns) designing one doesn't exactly inspire confidence that America could have gone it alone. The Russians had one from off the shelf they could use. Don't forget the Russians have been in space continuously for 30 years. NASA haven't. There's plenty of things that the Russians have realised that NASA haven't (like it's a bad idea to toss liquids overboard in space cos it condenses and jams the docking ports). And the Russians probably could have launched their entire section on one Energia if they had been allowed to. America has nothing that big.
The latest studies have show that for a first stage- LOX/Kerosene outperforms LOX/LH. There are lots of reasons for this:
a) the density of LH is really very poor indeed
b) (consequently) the thrust to weight ratio of LH engines is worse, kerosene gives much more thrust for the same weight
c) the weight of the vehicle goes down more slowly with LH, this increases 'gravity losses'
d) the density of Kerosene is very high
Anyway, bottom line is: LOX/Kero needs less delta-v than LOX/LH to get to orbit by about 6%. However, it doesn't give as much thrust per unit weight. But the density is 5x higher, which means that it is much easier to pack more fuel into the tanks to compensate. Once you realise that LH is more than 5x more expensive, and many, many times harder to handle then you start to seriously wonder why the Space Shuttle uses LH.
LH is good for upper stages though- the reduction in stage weight makes the lower stages smaller.
They will still be using SSMEs in Star Trek time - Scotty would sing their praises.
They may be good for deep space work. They're not as good as LOX/Kero for launching however.
The issue is more to do with flight rate. Reusables are several times more expensive to design, and tend to have less payload, (everything else being equal, because they have to be stronger to survive being reused).
Therefore to make them cost effective you have to reuse them many times to recoup the extra investment.
The offset for this is that the cost of the hardware itself is amortised over each reuse. So if the hardware costs $10 million, then if you reuse it 100 times, it only costs $100,000 per launch. Likewise the development costs.
But typically most launchers only launch 5-10 times per year, so the flightrate isn't there right now- it would take 10 years to recoup the extra development cost, and then there is interest on top...
In contrast, a cheap expendable can be knocked out very cheaply, and at these launch rates it's a win to do that, alas.
That is the working theory. However I am not aware of any proof; and I fail to see how a few thousand year old mummy in a glacier could have resolved a question about Neanderthals which died out tens of thousands of years ago.
Whatever this article implies, I'm pretty sure that no samples of Neanderthal DNA are known to science, so until we have some, the question seems open.
As an example, suppose all the white skinned people in the world were killed off [n.b. I'm not recommending this, I'm white!]. Would that mean that the remaining population were not descended from whites? Of course not. So the question is whether Neanderthals and human ancestors could interbreed. I don't know, and I don't think anyone has any evidence either way, but one thing is for sure, I bet they tried ;-)
No. Russian Proton is about $2500/kg right now to LEO. Sea Launch is about the same. Ariane is nearer to Space Shuttle costs per kg, but that's a geosynchronous launcher whereas Shuttle can only make LEO.
My rule of thumb is that Geosynchronous is about 3x more expensive than LEO; since you need more than 3 the payload at LEO to be fuel for a kick motor to push you up the last bit into GEO (an additional 3.8 km/s).
The cheapest expendables designed use, strangely enough, ship-building skills. So the skills are out there, for constructing these vehicles.
So it's 4x cheaper in fact.
He, he he. Who am I kidding? Actually none of the above. Saturn V was actually 4x cheaper than the Shuttle per kg; and that was expendable. The Russian vehicles launch for about 1/20 of the cost of the Shuttle, and they're expendable.
Studies have shown that cheap expendables can cost as little as $500/kg, cf $20000/kg with the Shuttle.
And its not high tech, its the money stoopid, that is holding back Moon and Mars. We have the technology.
Actually that isn't entirely correct. The idea behind IQ tests was to predict who would do well in higher education, and hence who it is worth letting in. As that, it succeeds pretty well- the correlation coefficient between IQ and academic success is something like 60% IRC.
Extrapolating this index further to other areas works less well; I believe that high IQ scores correspond to only about a 5% increase in earnings. Probably other factors like so called 'EQ' correlate better with the other 'success' metrics.
P2P has been with us since the very earliest days of the internet. P2P is NOT inherently inefficient. However a lot of implementations of P2P are inherently inefficient.
Trust me, you do not want the ISP fiddling with your traffic in some nefarious way in their network.
The design/look of their consumer webwatch website is much too poor for me to ever buy their conclusion. ;-)
On the other, they're expensive as hell, after 30 years of flying they're only just now looking like they're even close to getting them fully reusable (does it count if you have to remove them and tear them apart after each and every mission 'just to check'), and contrary to what NASA will tell you they aren't the only reusable engine out there (other engines aren't classed as such, mainly by NASA, but have had >2,000 seconds on them during testing, and that's about the same as most of the shuttle engines have, only the other engines probably need less maintenance.)
Oh yeah and they burn hydrogen. Hydrogen gives great exhaust velocity, but it's really seriously not very dense. This makes the tanks, fuel lines, and pumps much heavier, (that external tank costs $100 million, oh yeah and they throw it away each time).
Current thinking is that LOX/LH is about 6% worse overall than LOX/Kerosene for getting to orbit- the rocket needs more delta-v due to the extra vehicle weight and other technical issues and that swamps the extra performance of the hydrogen; oh yeah and LOX/Kerosene may not have needed an external tank to be thrown away because Kerosene is much denser.
All in all. Hey, it works! Anyway, pass the popcorn someone; it's still a rocket engine, and it makes a loud noise. ;-)
No, it will be unfair on the rest of us. They'll come out of prison with huge debts, and have to commit more crimes to avoid going back in for lack of payment. Insurance premiums would go up massively; and the thieves will get less money on the item once they have fenced it than the item is worth, so non criminals lose out all the more.
Sounds to me like the Germans just sent the bill a bit early; they should have sent it after the investigation was complete.
1984 came late it seems...
I don't know you from Adam; you may be a spammer for all I know, or a spammer may read this. Either would be bad. So no, I don't care to.
Um. As I understand it all of the manned Apollo missions went through the worst of the Van Allen belts- these belts are really nasty; the astronauts received about 1% of a lethal dose in the short time they traversed it; and they went through it twice; once on the way out, once on the way back.
Really? No. Not really. There's no way to know this was caused by him going into space. Lots of people get cancer anyway. The doctors or coroners sometimes say otherwise, but it's mostly just a best guess in nearly all cases, and it's frequently not terribly scientific.
Yes, maybe more, maybe less. What's wrong with that? Even if one of them dies of cancer we won't know whether that was caused by the radiation- there is no test for radiation induced cancer- cancer is cancer (pretty much.)