Nuclear Rocket Petition On White House Website 205
RocketAcademy writes "A petition on the White House website is calling for the United States to rapidly develop a nuclear thermal rocket engine. Nuclear rockets are a promising technology, but unless NASA develops a deep-space exploration ship such as Johnson Space Center's Nautilus X, a nuclear rocket would be wasted. Launching nuclear rockets may pose regulatory and political problems as well. Practical applications may depend on mining uranium or thorium on the Moon."
Why not have a petition for something USEFUL? (Score:5, Funny)
Like free hookers / pot?
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Like free hookers / pot?
Free hookers are called WIVES.
But in the end, they are pretty expensive.
Re:Why not have a petition for something USEFUL? (Score:4, Insightful)
Not so.
Hookers put out reliably when you pay them. Wives do not.
Re:Why not have a petition for something USEFUL? (Score:5, Insightful)
One step at a time. It's more useful than a Death Star.
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Don't forget the theme park and the blackjack!
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Like free hookers / pot?
If hookers were free wouldn't they then fail to meet the definition of hooker? I think they would transform into sluts.
Re:Why not have a petition for something USEFUL? (Score:4, Funny)
Re:Why not have a petition for something USEFUL? (Score:4, Insightful)
If hookers paid by the state existed, YOU would get screwed.
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So you are familiar with the nature of politics!
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Caution, political double speak present.
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Re:Why not have a petition for something USEFUL? (Score:5, Interesting)
I love the petition website as an attempt to get people a little more involved with public policy but (maybe because I read Slashdot too much) so many of the petitions seem to be nonsense like "I want a nuclear powered spaceship to Andromeda." Or "more funding for SETI." Addressing climate change is a better suggestion, but the president has attempted to address climate change in a few ways already. Doing more or something different isn't a bad idea, but you would need to be more specific - a requirement for city planners to implement some manner of public transportation, a plan for reduced dependance on beef, etc.
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No, it may also mean developing nuclear power more, or imposing efficiency standards on wares. Le's talk about standards.
As a European, one of the stricking thing about America is the absolutely dismal standards in housing construction, household applicances, cars, etc. Sure, things are a bit cheaper, but the TCO of all those things is really bad compared to euro stuff. It seems people only look at the sticker price, and don't think about the costs down the road.
So in fact, in the US there is quite a margin
Re:Why not have a petition for something USEFUL? (Score:5, Insightful)
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That's because in the US people are trained to always go with the lowest bidder and to only look at the short term return on an investment. My dad was a high-quality remodeler for many years, and it was always a challenge for him to make a customer understand that the guy with the lowest bid was not always the best choice.
Remember that the government "lowest bidder" laws were put into place in response to rampant and blatant contract-fixing. In the private sector, you get what you pay for usually.
Re:Why not have a petition for something USEFUL? (Score:5, Insightful)
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Indeed. Annoying as hell that they decided to fix one flawed process by instituting another even more flawed process.
If you think about some of the high money contracts it covers, it makes a lot of sense. You want to pave 100 miles of road, you put our specifications for asphalt depth, quality, etc. - all the parameters covering the needed job. Then let all bid on the job. This eliminates somebody's brother in law from getting the contract unless he is the lowest bidder willing to meet the specs.
Where is fails is on the cutting edge of technology. Those potholes on the parkway that appear in the same place every winter
Re:Why not have a petition for something USEFUL? (Score:5, Interesting)
As a European, I generally agree, especially in terms of household construction, and insulation. These are easy things to do, and pretty easy to regulate when you give planning permission.
However, TCO falls flat on the floor with loads of stuff like lightbulbs, because they fail to take into account the fact basically _no_ energy is wasted when the house is being heated. All the energy goes to heat. All the energy heats your house. The _only_ time an energy inefficient light source is wasting energy is when you are not heating the house. For most of the UK population, that's about 1/4 of the time.
Solar panels are an absolute joke in the UK, they're a middle class government subsidised tax break, and no more. Seriously - the one place you don't want a solar panel is in the UK, it's got about the lowest sunshine hours in the world. I'm actually talking from one of the driest places in England - just over 12 inches of rainfall annually (honestly) - but we still get a lot of cloud.
European cars have led the world in being energy inefficient over the last 20 years or so. We left our 100mpg [wikipedia.org] production cars behind a long time ago.
Are things really cheaper in the US? Broadband & mobile plans seem more. Petrol's cheaper, because it's taxed a hell of a lot less. Apart from that, I don't really know... all I know is that cheese is expensive in Australia. On that note, I depart.
The light bulb issue (Score:3, Insightful)
But it is quite a bit more than that in countries south of UK! Especially if you have air conditioning, the traditional light bulbs put you in the absurd situation of using energy both to heat and cool the room at the same time... Another thing is that the light bulbs in typical lighting fixtures are inefficient as heaters. Most of the
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However, TCO falls flat on the floor with loads of stuff like lightbulbs, because they fail to take into account the fact basically _no_ energy is wasted when the house is being heated.
Light bulbs are a very inefficient way to generate heat, compared to central heating. The amount of heat generated per watt, per gramme of CO2, per Pound it costs you is very poor.
Solar panels are an absolute joke in the UK, they're a middle class government subsidised tax break, and no more. Seriously - the one place you don't want a solar panel is in the UK, it's got about the lowest sunshine hours in the world.
Except for maybe anywhere further north. Solar works fine here; it generates significant amounts of power year round for most of the population.
European cars have led the world in being energy inefficient over the last 20 years or so. We left our 100mpg production cars behind a long time ago.
I suppose you have not noticed all the new diesel and hybrid cars with high MPG ratings on the market, or the very high fuel prices we have.
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I agree with the first two points, however the GP 3rd point is correct. For example, a Prius T3 will give 76.4mpg (Extra-Urban, as long as you're not trying to drag the batteries around at 80mph with a 1.8l engine). The Renault Clio 1.5 dCi 90 ECO gives 88.3mpg. Granted, the AX was driven in ideal conditions and most likely by a well trained driver, however that was 24 years ago.
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Light bulbs are a very inefficient way to generate heat, compared to central heating. The amount of heat generated per watt, per gramme of CO2, per Pound it costs you is very poor.
There is basically no inefficient way to generate heat. It's just energy. One hundred 10 watt speakers are the same as ten 100 watt lightbulbs are the same as 1 kilowatt heater. The only way you lose energy is if it leaves your home. This is basic stuff.
Heating your home with gas, oil, wood or whatever may be more efficient
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Yes, and I'm paying my taxes to help you achieve that. That's what subsidies are.
I'm personally not anti-green, nor anti-home improvement. However, your solar power in a northerly cloudy country is in my opinion not a good way to spend my money. I'd be much happier funding a similar initiative in the Sahara, because then it'd be a hell of a lot more efficient.
ps. I'm only just south of you - Woodbridge.
Re:Why not have a petition for something USEFUL? (Score:5, Interesting)
Housing construction: In Europe, current population is either stagnant or shrinking in most countries and the population generally doesn't move around much - it's not entirely uncommon for a family to still be living in the same house their great-great-grandparents moved into during the start of the Industrial Revolution. In America, it's a different story - our population is steadily increasing through a combination of natural birth rates and mild immigration, and our population is arguably one of the most mobile on Earth. Consequently, American housing reflects American needs - it doesn't need to hold up multi-generationally because it won't be in use multi-generationally. It just needs to hold itself together long enough to get the kids into college so the parents can retire into a different, smaller house, preferably one in a warmer climate.
Household appliances: Eh? All the appliances in my apartment are at least a good 15-20 years old and they're holding up okay. Bear in mind here that, if we're going to get serious about energy efficiency, we probably shouldn't be encouraging people to use 50 year old appliances that work "just as well as when they were new".
Cars: You're kidding, right? I've seen European cars. I've owned European cars. There's a reason they're a niche commodity in America - they're expensive and don't hold up nearly as well under American driving conditions as Japanese and (some) American models. Plus, due to the higher concentration of population in Europe, mass transit is used more widely and the road system isn't generally as accommodating as America's - this means that there are a lot of poorer Americans buying cars here that would normally just take a bus or a train in Europe, which means there's a large, paying market of people here that can't afford a C-Class. I'll note that there are several European brands that tried to set up shop here and failed miserably, all with horrific reputations for reliability by the time they were done (anything British, French, and Italian comes to mind, with FIAT doing its best to prove it's learned a thing or two since the last time they were here). Even Volkswagen has a well-deserved reputation for shaky reliability and build quality out here, though I've heard that has as much to do with the price point VW's trying to meet in the US as it does anything else.
Put another way, Americans look at TCO just fine - we're just operating under an entirely different set of parameters than Europeans. Well-built 100-year-old houses are still 100-year-old houses with 100-year-old wiring, 100-year-old plumbing, and 100-year-old room sizes - in our case, we have enough open room and enough money to replace those with newer, better designed houses, and since we know we're just going to replace them again in 25-50 years, we're not going to overbuild them. Similarly, the American definition of a "well built" car is wildly divergent from a European definition - since we practically live in our cars here, we want something that will last 250,000-300,000 miles and/or 10-15 years of constant day-to-day driving first (that's 400,000-500,000 km), we want it to be comfortable to sit in for long periods, and if it can also go around a corner without swaying to-and-fro, so much the better; this, I'll note, is the opposite order of the European definition, which better reflects European needs and conditions. And so on.
The original... (Score:5, Interesting)
The NERVA test engine is on display at Johnson Space Center, as I understand it.
Being 40+ years out of date, I imagine they'll have to spend billions to repeat the original work, but I'd hope that the fact that we already built a working nuclear rocket would mean that developing a new one wouldn't be overwhelmingly difficult.
Re:The original... (Score:4, Informative)
The NERVA test engine is on display at Johnson Space Center, as I understand it.
National Geographic confirms your understanding [nationalgeographic.com].
Re:The original... (Score:5, Insightful)
Being 40+ years out of date, I imagine they'll have to spend billions to repeat the original work,
The real cost to ressurect old aerospace technology is in remaking the molds and figuring out the exact composition of the materials used.
If NASA saved any of the old molds/dies or documents, it'll save them a lot of money and effort.
And I'd like to point out that "out of date" is a questionable statement when we're talking about rocket technology.
The R&D has already been done and it's not like the old designs deteriorate with age.
Computers aside, most of what's done today isn't very different from 50 year old rocketry.
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The big difference modernising a 50 year old design would bring is a huge increase in weight efficiency - new materials, new understanding and better ability to manage finer tolerances.
You could take a 1950s Boeing 707 and remove about 50 tonnes from it just through the above.
If you hire corrupt defense contractors.... (Score:5, Informative)
Being 40+ years out of date, I imagine they'll have to spend billions to repeat the original work, but I'd hope that the fact that we already built a working nuclear rocket would mean that developing a new one wouldn't be overwhelmingly difficult.
If you hire big bloated corrupt incompetent defense contractors it is guaranteed to take longer than the original and costs BILLIONS more:
Remember that all the above was in response to the destruction of Orbiter Columbia during reentry ten years ago. Oh, for Constellation haters: the Ares-I 1st stage now exists (ATK has test fired several of them and has essentially finished it .... they are just optimizing and characterizing now) and it will fly as part of the SLS system...... now if we just had an Orion and an upperstage with a J-2 derived engine......
The nuclear engine is a great thing..... we developed it in the sixties and even ran them at a test site in the desert..... but if you hire some big aerospace corporation that has been sucking on the government teet for decades and is used to delivering defective garbage to the taxpayer, demanding more for that garbage than was originally bid, and being rewarded by being offered new projects ..... well you're just gonna spend billions and either get nothing or get junk. (the normal pattern is that you spend billions and years and then eventually cancel the program so the taxpayers get nothing for the money but a few desktop display models...... google X-20, X-33, X-38, OTV, NASP, A-12 ....)
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Giving it to some aerospace contractor wasn't really to make the development faster or cheaper. It's all just a kickback to the guys who donated a ton of money to some particular politicans' campaigns.
The difference between a project done by government employees and a project done by a private contractor is that the former isn't in it for the money. And usually, that means they're doing it for pride. Pride is more productive than any amount of money.
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I think it helped that Apollo had a fixed deadline to work to, and the contractors could not therefore just drag things out and keep sucking up money on the project. There was no question of it being randomly cancelled in a few years by the next administration either, NASA was well funded and the goal was very clear.
I hope the Chinese are serious about manned moon missions. That might convince the ESA, JAXA and NASA to get serious about it.
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So? That's about as relevant as having a LEGO Millennium Falcon on display at Johnson Space Center. NERVA isn't a flight ready engine, it isn't even close to being a flight ready engine. It's a technology demonstrator.
But the real problem is, nuclear thermal propulsion is a solution in search of a problem - a billion dollar engine doesn't make any sense without a multi--tens-of-billions of dollars spacecraft sitting o
Re:The original... (Score:4, Interesting)
“This is not a model,” NASA physicist Les Johnson says as we gaze at the 35-foot-tall assemblage of pipes, nozzles, and shielding. “This is an honest-to-goodness nuclear rocket engine.”
-- From Nat.Geographic (link above)
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it isn't even close to being a flight ready engine. It's a technology demonstrator.
Had I said it wasn't a nuclear rocket engine, you'd have a point.
Close enough for me. You said it wasn't a (flight ready) engine. His point seemed valid, and your complaint petty.
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I don't think you're qualified to talk about this subject if you can't understand the massive difference between a "technology demonstrator" and "a (flight ready) engine".
For example - it could require vast amounts of support hardware - it's not uncommon on test engines to have things like the turbo pumps and tanks and control hardware completely external to the engine and if you tried to fly with them they'd be too heavy or wouldn't package correctly or any other a a thousand little problems.
The materials
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That it's not a flight ready engine is a stone cold fact.
Deliberately misreading that in order to fabricate something from whole cloth, that's childish. Calling me petty for correcting that fabrication... well, that's beyond childish.
Grow the fuck up and learn to deal with facts. Or piss off back to the Barney and My Little Pony message boards with the other kindergarteners. I don't care which.
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In other words - it wasn't a flight ready engine and had never been tested in a flight ready configuration.
... people keep treating something that wasn't flight ready as if it was - and keep acting as though it would have been flight ready on schedule and on budget in precisely the way virtually no other program ever was.
I know it's democracy and will of the people, but (Score:4, Insightful)
In this case I believe the judgement of professionals at NASA is worth more than of some random petition signers. Give NASA a bigger budget and let them decide how to spend it.
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Maybe it's entrepreneurs you should be consulting. From the article: "One of the more interesting concepts from this period did not come from NASA but from a model company called MPC."
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No, the United States of America is a democratic republic(started as a republic, but the 17th Amendment, including how states, which are sovereign entities and thus equal to the national government, hold referendums and such). We elect representatives, who hold authority to make governmental decisions on out behalf. It is a generally held, but false belief that the US is a democracy; democracies are a farce, at best(read Federalist number 10).
Authority and power are derived from the citizens of the US, but
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While I agree with the modding, I'd flip that around - the US is a republic by definition; it uses (and has always used) representative democratic principles to elect its representatives in that republic. There has not been a democracy (form of government) since ancient Athens because, like true communism (and I mean not the dictatorships we have called communism), it doesn't scale well.
Good and Bad (Score:4, Informative)
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Both the US and the USSR have launched nuclear reactors into space (not just those radioisotope decay generators, real reactors). Some of them are still up there in graveyard orbits. Launching a nuclear rocket in a cold shutdown and only bringing it into full active state when safely above the atmosphere wouldn't be much different.
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It still would take years to get past the public perception of nuclear, despite the fact that a reactor in cold shutdown would have little risk, even as a "dirty bomb" explosion that spread all of its radioactive materials around. Public perception is still any amount of any kind of radiation is bad.
The USSR had a bunch of nuclear powered spy satellites, but AFAIK, the only non-radioisotope reactor the US has launched into space is SNAP-10A (in fact, confirmed [wikipedia.org]). I vaguely remember the Soviets had nu
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Yes, build it in space and work from there. I think we're going to have to re-evaluate the idea of spaceships taking off from earth in the same way that cargo ships can't go across land.
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> A failure on launch could result in releasing radioactive
> fission products over large areas.
Wrong. The reactor would be launched cold, prior to having ever been fired up. In that state it would contain no fission products and fewer curies of radioactive material than an RTG. It also (like an RTG) would be constructed in such a way as to almost certainly survive re-entry intact.
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No, it's the "we would build a perfectly good engine, then not use it when it makes the most sense so that I can win an argument on Slashdot." argument.
But that isn't the case. Nuclear rocket engines have high Isp and low thrust. It only makes sense to use them as an upper stage, in space. Turning them on in the atmosphere would just waste fuel. As an upper stage engine, the reactor would be cold until the rocket was in space ("when it makes the most sense").
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Nope
NTRs have high ISP but (compared to Chemical rockets) low thrust. The whole point of the ffirst or zeroth stage is high thrust (the SRBs for example are very high thrust, but low ISP). Nuclear rockets are great for a second stage or later but they can often have a thrust to weight ration http://www.projectrho.com/public_html/rocket/enginelist.php#table for data.
Now an Orion drive on the other hand, yes that's a great way to get off planet nuclear - but unlikely to be used.
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Space travel is hard and there are three steps. The launch, the travel and the landing or orbit. For unmanned travel, there are several options. One of the most interesting might be an ion drive, which would accelerate a ship to 300
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The reactor would not be powered up until late in the launch, possibly not even until it had reached parking orbit and was leaving for its destination. For NERVA launches which started the reactor before reaching orbit, the trajectory was chosen so if there was a failure the reactor would crash in Antarctica... unfortunately that made it far less efficient so it's debatable as to whether it was worthwhile.
Re: Solar Thermal (Score:2)
Nuclear rockets have a much higher specific impulse than chemical rockets.
Solar Thermal has the exact same higher specific impulse, because both heat up Hydrogen to produce thrust. The only difference is the heat source. Solar Thermal is lighter than Nuclear Thermal (reactors are heavy, and require shielding), and completely avoids all the issues with Nuclear (protests, accidents). The only place to consider Nuclear Thermal these days is if you are going to Jupiter or beyond. Jupiter has intense radiation belts, so extra shielding is a moot point, and beyond that distance sun
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Seams to me that Solar-PV-ion drive is the only real way to go..
Anything else is going to run into material thermal limits needed to provide the directional trust vector needed.
As for powering a moon base. Better to string a HVDC line near the poles, and collect the electrical energy produced energy from half a dozen PV installations. No moving parts, redundancy, no refueling. Most of the elements needed for construction in abundant supply.
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Do you think for a second that the people that oppose nuclear power on earth aren't going to care about the moon? Keep in mind, these people don't really care about nuclear power, what they actually oppose is progress. I've met plenty of them, they want to live in straw bail houses, eat organic food, don't get their kids vaccinated etc... They're like a newage Amish. Rational arguments will not sway them. If they're willing to let people starve rather than eat GM food and their own children contract deadly
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I wish they'd spend more time protesting nuclear weapons. You know, the ones aimed at them.
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There will always be extremists, but what is worse is those who sympathize with them - they are the ones who rally behind the cause without knowing any facts and make progress politically unpopular. Such people should be made to watch the Star Trek DS9 episode Paradise [wikipedia.org] (the WP description doesn't do it justice, watch it on Amazon Prime if you can)... While the "leader" in that story is not anti-progress for religious reasons or out of any irrational fear (the two common causes for the mindset), I think div
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Do you think for a second that the people that oppose nuclear power on earth aren't going to care about the moon?
Well, it's harder for them to picket the mining site.
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I've met plenty of people like you. Fingers in your ears, la la la I CAN'T HEAR YOU la la la. Not interested in what others are actually saying, you only want to rage against the over-simplistic boogymen that you blame for everything.
People object to nuclear power on earth because of the consequences of serious problems, but obviously they are massively reduced when the reactor is on the moon. Waste is a non-issue. The problem of the reactors being run by idiots still exists (NASA management has proven itse
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Can I vote against this? (Score:5, Interesting)
I would really like to be able to vote against some of the stupid ideas on the White House web site. It would help to have a crowd function to weed out some of the wackier ideas.
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I agree. These petitions (What's next? Convert Cheyenne Mountain into a wormhole research facility?) dilute what little influence the petition process already has. Someday the government will be able to point to all the wacky petitions when they really need to trivialize a valid petition that they consider a threat.
Want to do something for science? Look at the Brits. They petitioned for an apology for the way the government treated Alan Turing. And they got an uncharacteristically honest and unqualified apo
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I just compared the highly voted vs. the not-so-highly-voted petitions at https://petitions.whitehouse.gov/petitions [whitehouse.gov] . It made me question the wisdom of universal suffrage.
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These petitions dilute what little influence the petition process already has.
People watched the first few with great intensity. The White House dodged any "tough" peititions and made a mockery of it. The current round are a backlash against the pointlessness of the process. At least the White House honestly answers these. It's an improvement over the serious petitions they ignore.
Pissing in the wind (Score:2, Insightful)
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Yeah, well, last week's big petition was to build a Death Star, that got 34,435 signatures. So, yeah, they're toilet paper.
They answered that petition, though.
https://petitions.whitehouse.gov/response/isnt-petition-response-youre-looking [whitehouse.gov]
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"Pissing in the wind" is about something unpleasant blowing back at one. What you're talking about is "Pissing in the sea".
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Neil Young.
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The punch line on this joke will hit in 25 years when his by-then grown-up supporters realize that the TRILLIONS of dollars of new debt he heaped upon them and their kids has made them the 1st generation of Americans ever to be so abused by their predecessors that they will spend their entire working lives paying the interest on the maxed-out national credit card. They will have a lower standard of living than their parents .....
And here I thought that generation was those born 1960-1980. Obama is not anything more than this generation's Reagan. Yawn. Same politicians, different generation. But don't spread the blame where it belongs, make sure you identify the other party in your complaints.
So its only a matter of time before ... (Score:3)
"we the people" white house petitions are perceived as being nothing more than hollywood babel.
Do you really think there are 25,000 people who have any clue about this subject matter of the petition?
Imagine the "Death Star" petition and the white house response. if that ain't hollywood... what is.
Here is one for contrast: https://petitions.whitehouse.gov/petition/provide-each-taxpayer-independent-voice-where-taxes-they-pay-are-be-allocated-and-used-all-tax/cxBlXQht [whitehouse.gov]
lets prove the point.
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Typical agent smith style off topic tactic, but ultimately all systems of belief are based on abstraction, be it religion, government, military, economy and money, etc.. So what world of abstract constraints are you living in? Certainly not one of crowd sourcing government as Iceland has done to successfully economically recover.
But thanks you for helping to make my point regarding the hollywoodness of the "we the people" white house petition site.
Project Orion (Score:2)
Nuclear Rockets (Score:2)
Yaaaaaaaaaaaaawwwwwwwwwwwwnnnnnnnnnnnnnnnnnn.
Someone wake me up when we get to the 21st century tech.
-Hack
Not very useful the way it's worded. (Score:5, Interesting)
Nuclear Thermal Rockets can have a higher efficiency than than conventional chemical rockets, but it's not as much as you might think. There's a limitation that to have a higher exhaust velocity in a thermal rocket, the exhaust needs to be hotter. And it can only be so much hotter before your reactor starts becoming molten rather than a solid. Which means that efficiency tops out at a bit less than double the exhaust velocity of conventional rockets.
Now, that's still useful, if you can get enough thrust to get up off of the planet (and to overcome the weight of the reactor in the process), then you might be able to lift quite a bit more into orbit. Except the petition is for an NTR that would only operate in space. And in space, where you don't really have to worry about the amount of thrust, and your speed is limited by your fuel and your exhaust velocity, things like ion drives can reach efficiencies an order of magnitude higher, or more. Which means, an NTR in space only wouldn't be as useful, compared to nuclear-electric or solar-electric propulsion.
I suppose an NTR not used for Earth surface to orbit might still be useful in landing or taking off from other objects. Really, that's where its strength would be, if you can get it to have high enough thrust, then it would be useful for getting things into orbit and back, as a surface-to-orbit ship. But as far as orbit-to-orbit ships go, ion drives and other electric propulsion can get a lot more speed out of the same tank of propellant.
Re:Not very useful the way it's worded. (Score:5, Informative)
Hmm, ion engine Isp of 20000, say. Thrust of 10 newtons. All-up spacecraft mass of 75 tons.
Time to escape speed from LEO, about 22 months.
NERVA, Isp = 800, say. Thrust of 300,000 newtons. All-up spacecraft mass of 100 tons.
Time to escape speed from LEO, about 18 MINUTES.
NERVA isn't a replacement for an ion drive on a deep-space probe, it's a replacement for a chemical rocket on a (large) manned spacecraft going from LEO (or higher) to a similar orbit around the moon/mars/venus/wherever.
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"Hmm, ion engine Isp of 20000, say. Thrust of 10 newtons. All-up spacecraft mass of 75 tons. Time to escape speed from LEO, about 22 months.
Next generation ion engines [newscientist.com] produce far more thrust.. (`~833 newton/sec).. reducing time to escape orbit to a little over week.. Fringe benefit, the space craft would only consume ~4 kg of xenon to accomplish that task..
That leaves all other propulsion tech, including nuclear in the dust so to speak..
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here is a working link [democratic...ground.com]..new scientist link seams to SOL
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Ion drives get you delta-V at low cost, but that delta-V takes time. This matters if you have meat sacks on the mission who persist in eating and breathing and need to minimize their exposure to cosmic radiation.
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NERVA got an Isp of about 1200 before it was scrapped.
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Nuclear Thermal Rockets can have a higher efficiency than than conventional chemical rockets, but it's not as much as you might think. There's a limitation that to have a higher exhaust velocity in a thermal rocket, the exhaust needs to be hotter. And it can only be so much hotter before your reactor starts becoming molten rather than a solid.
So have a gaseous reactor [wikipedia.org].
what a waste (Score:3)
We have energy shortages here, why would we waste fissible materials on this? We need to solve problems on the ground first before we consider using limited resources that will be spent in space with no possibility of recycling.
Thorium on the moon? (Score:2)
There's tons of thorium right here on earth. Mining it on the moon sounds pretty impractical.
Re: (Score:2)
Lifting a ton of material from the Moon to LEO requires a lot less thrust than lifting it from Earth. Even better, lifting it to orbiting the Moon requires so much less thrust that you could almost throw it there.
How about a linear accellerator using nothing but electricity to lift materials from the Moon to LEO?
e-Petition (Score:3)
I wonder how long do we have before they stop e-Petition completely. e-Petition is asking awkward/unrealistic questions. We already had a request of building a Death Star.
Re:stahp (Score:5, Insightful)
This.
Seriously, anyone who thinks the white house actually considers any of these petitions is incredibly naive and impressionable, which is, of course, the whole point - making a bunch of naive, impressionable voters believe the administration actually gives a fuck what they think.
Re: (Score:2)
Or maybe it's about getting your ideas out to a wider audience? Even on Slashdot it's evident that most people don't have the foggiest clue what a nuclear thermal rocket is or how it works, there are lots of people saying that launching one would destroy ecosystems or be politically nonviable. Never mind that spacecraft with nuclear reactors (not as large of power perhaps) have been launched before and a nuclear thermal rocket doesn't release any significant amount of radioactivity. So yeah, you're not g
Re: (Score:2)
This country was founded as a Republic, it is wrongly promoted as a Democracy but in actuality it has become an Oligarchy. And when it gets right down to it, its about money. So where do you want your taxes spent or do you typically go into a store and hand the cashier your money and take whatever they give you? How about we the people take control of budgeting and accounting by each of us saying where to allocate the tax funding we individually supply our employee government with? That way the representati
Re: (Score:3)
I really thought blowing up planets was their policy.
One country at a time.
Re: (Score:2)
Nuclear thermal rockets still require an exhaustible, usually liquid propellant source.
Plenty of seawater lying around.
Re: (Score:2)
If you pump hydrogen through at close to melting point of your engine you can get an Isp of about 1200. (compared to shuttle main engine which gets just under 400)