Again, you think this isn't being done, in regards to a particular article having citations being used as where the original source material was posted from? I do it all of the time, and some of the better articles have both a bibliography and even footnotes. When there is an editorial dispute, the citations are especially used to prove factual quality. There are even facilities within the MediaWiki software to merely put down an ISBN number and that will link you to pages like Amazon.com or Barnes & Noble so you can look up the dead-tree citation and get a copy of the book yourself, or even look it up in your local library. So even a random citation for just about anything can usually be found, and found quickly except for unpublished sources. And yes, there are mechanisms to directly tie these references to the poster directly who added both the citation and the content of the article.
The trust rating is more social, as in the fact you get used to the same set of authors and after awhile you get used to who is likely to mess things up and who does a solid job of fixing things up in an outstanding manner. You also have access to the edit history of each author that you suspect may be doing some damage, and there are even structures within Wikipedia to deal with problem users. Outright trolls (the GNAA has moved into Wikipedia lately) are dealt with harshly, to the point their IP addresses are banned from even participating. There are some problems with doing that, but even the "innocent" people who get burned due to trolls are allowed to appeal their case of banning.
In the case of Wikinews, citations are considered "essential" and are grounds for deletions if you don't provide a direct news source (or in that case don't clearly identify that you are the original journalist creating the account as an eyewitness). If you want to see how each reference is thouroughally checked and identified, try to get in and edit a Wikinews article, particularly on a front-page article or even a developing story. Try to introduce a bogus "fact" without a citation reference, or even "make up" a reference. I promise you that it will be culled almost immediately.
Wikipedia articles take a little more time before the vetting occurs, but it does occur as well in even some of the most obscure articles that I've seen. Almost every subject you can imagine has at least a few people that really are knowledgeable about that subject, and getting away with introducing outright BS (like the Moon is made of cheese or that Bill Clinton was the first astronaut in orbit) is going to be edited out over time. Wacked out UFO conspirists generally don't get much of a chance to promote their theories, unless the article is specifically about one of their theories... and even then the citation issues still hold.
It appears that you think the trust metric applying to both the content entry and encouraging citations should be more rigerous, and required, even put into the software of the contributors putting in the content. I would dare you to find even a peer reviewed scientific paper that has been published which has that thourough of a review where each sentance has been put under that kind of scrutiny. I know of PhD dissertations that should have had that kind of review that didn't (where you would expect that kind of microscopic review process).
While certainly things could be improved, I find that the current review process is very healthy. I've even written extensive articles myself and when I've made even minor typos simply due to the huge amount of content I've added, they have been corrected by other readers and contributors. And that is on very technical subjects where the typo would never have been caught by a spell checker. I did review the change and discovered that I made a mistake... again a part of the review process.
There already is a sort of "windowed" review area that each user has available to him/herself. You can select each article you want to "watch", and even remove articles from you "watch list". If there is something you have been working on and somebody makes a change, you can run over and see what those changes are right away.
This "Window" is extensiable for up to 7 days for you to review anything that you are interested in how it has changed. I use it all of the time... usually to introduce myself to new users or in fighting arguments on topics I'm interested in. Most of the content of Wikipedia is covered by at least one or more of these "watched" pages by some user, so it tends to keep vandalism down just through that system alone. If you don't like the changes to the article, you can always "revert" the changes, or get into a discussion about why you didn't like the changes, together with a datestamp to the exact change and by whom did the change.
As far as formal peer review to "publish" changes, that is in part what Jimmy Wales is talking about with the "Wikipedia 1.0". They want to push articles into a higher caliber of quality and make only those articles that may be of high quality to make that next step of being "published"... with active peer review to accept or reject the nomination.
That is already there. Look at the history tab for any article, and you can get an edit by edit view of each article, who made the change, and (usually) why. It will show diffs between versions of the article, and point out who is the screwup and who did the deliberate vandalism. If you have a known vandal, you can even scan through just their edits and try to undo their damage... even if the article has changed since they've done the damage.
You also have the "option" of linking via URL to only a specific version of a page, if you want to link to just that article.
Images are a bit more problematic as the software treats multimedia content a bit different from text. There still is a history log of the changes to media files, and you can "go back in time" to earlier versions, and even "revert" to that earlier version if you don't like how the image has been changed. There does need to be a link between a historical article version and the historical media, but that is an issue for a later release of the software underlying Wikipedia.
Basically, you can do exactly what you are talking about right now.
The problem you have with a citation list is how do you provide it? A web crawler through all of the internet? How do you deal with "citations" of dead tree content? That is an impractical solution. A citation list of articles that link to an article within Wikipedia is already present and running right now, and that is a fair metric that is often quoted. There is even a ranked list of "links" to articles that don't even exist! (The link exists, the article it links to doesn't, however.)
As far as "web of trust" is concerned, that is something that is proposed in a future version of the MediaWiki software that is behind Wikipedia. The rating systems are being proposed. If you want to join in the discussion you are certainly welcome. The decisions on how to accomplish this havn't been decided yet.
As has been pointed out elsewhere, other sources of knowledge (news websites, slashdot, printed books, newspapers, etc.) also have trust problems with them as well... and people decrying that certain media outlets are less than honest to their subscribers/viewers/readers/listeners. I would argue that Wikipedia even now does a better job than most of these other information sources, and it can be pointed out some substantial biases are found in more traditional information sources.
Of course there are "trusted" information sources that we all use every day, and of that I agree that we all have an internal "BS" detector. Unfortunately it doesn't always work the way we want it to work in every case.
The Air Force got their hands into the mess right at the beginning. The Shuttle together with what later became the ISS was supposed to replace the Air Force Manned Observation Laboratory.
The U.S. Air Force, back in the late 1960's, had this ambitious militarization of space program where they would have a permanent manned space station with Air Force officers manning weapons that could be launched or "observed" from space. A total of about eight astronauts were actually selected and went through quite a bit of training and design work. This was seperate and distinct from the NASA astronaut selection program (more civilian in nature...but did allow selection of military personnel). These astronauts reported directly the the Secretary of the Air Force, not the NASA heirarchy.
Later these astronauts were moved over to NASA without having to go through a normal selection process, but many of the Air Force mandates were also "rolled" into NASA projects. This was done at the end of the Johnson administration.
One of the things that the Air Force did was to build a complete second launch facility at Santa Barbars, California at the Vandenburg Air Force Base. The intention here was to be able to launch the Space Shuttle into polar orbit. While the launch facilities were built, the Shuttle has never been launched from this facility. The runway strip at this base was also design to handle an emergency landing of a shuttle, although Edwards AFB is comparatively nearby and would be considered a prime recovery area for a polar orbit as well.
There were other screwy things the Air Force did to mess with the design parameters of the Shuttle, and there were several classified missions the Air Force flew using the Space Shuttle that for some reason had to have the current characteristics that are in the Shuttle program. While some details of those mission have been declassified (including what astronauts flew on them), there are some missions that are still very black in terms of what really happened.
In short, yes, the Air Force had a big hand in what happened with the Space Shuttle, and the design would have been quite a bit different had NASA alone been involved with the design process.
I would love to find a solid reference to this. I've read a number of reports about how simply silly the whole business of Freon refrigerants has come about and the only legitimate "environmental" reason for not using Freon is simply one:
The patent on Freon ran out and DuPont Chemicals needed an alternative they could continue to make more money on. The environment of their board room wasn't plush enough and needed environmental change. Believe it or not I've actually seen that reason used in an environmental impact statement (for killing other projects).
At least if you look at when the patent on Freon ran out, it is very coincidental as to when all of the "Ozone hole" stories started to surface regarding the ill effects of Freon and other chlorine-based aerosols in the upper atmosphere.
Yes, I've read and even seen demonstrated the effects of Freon on rarified ozone... don't flame about that. Freon was an incredibly safe chemical in a large number of ways that its replacements havn't really been all that useful toward... and if it is killing people you can point to (like the Shuttle astronauts), that is more than enough reason to think it was a poor idea to switch.
The Saturn V with Apollo capsule was 370 feet tall... the original purpose. Actually there was an even larger rocket design that was planned, so yeah, 500 feet does seem to sound correct.
The rooftop is over 525 feet tall. They may have to "cut" a new door frame on the exit in order to accomodate such a large beast, and possibly rework the primary cranes, but it could be done. A large rocket wouldn't force a major redesign of the facility or force a new building to be built.
The issue with the shuttle is; it's an incredibly complex machine, and some of the problems it was designed to handle are very difficult problems.
Yes, the Shuttle is a complex machine. I've heard that over and over again each time I see a shuttle launch program on TV, or when astronauts talk about it.
That is precisely the problem... not the ice damage or the configuration. Any engineer from any discipline can tell you that each time you add a new part or increase the complexity of a machine that you are likely to screw it up.
At their heart, a rocket is a very simple machine. You throw "stuff" out the back end of the rocket, and as fast as you possibly can. The trick that modern rocket builders need to deal with is that to achieve orbital velocities you need to have a rocket that sends "stuff" out so quickly that it reaches insane temperatures, and even incredible temperature differences (going from -200C to 4000C in less than 10 seconds for the fuel). You also need to have a "fuel pump" that can effectively pour a controlled but huge volume of fuel at constant (or at least consistant) pressure. Indeed, it is the design of an efficient turbo pump to push fuel into the combustion chamber that most rocket scientists spend their time. And where most of the complexity comes in. Dealing with cryogenic fuels also has some additional problems (in the case of the shuttle).
The trick to reduce errors and failures is that you have to simplify the idea and approach. One solution to this issue is that if you have an assembly line of rockets being built, you have other incentives to simplify... mainly because it gets cheaper to build them in the first place when there are fewer complex parts.
The current fleet of Space Shuttles are each hand-crafted and in many ways unique craft each in their own right. They each have a very interesting history, and in some areas you can't "mix" and "match" or change parts (although sometimes NASA tries real hard in this prespect).
As you also pointed out, there were problems with the tile system. When it was first proposed, even before STS-1 with Columbia, there were quite a few complaints about this heat-protection system. There was at the time a "wait and see" standard mantra coming from NASA, to see just how effective it was. And indeed it has been quite successful in a number of ways, but it has proven to be far too fragile for repeated flights.
The other thing that a redesigned Shuttle would have in its favor is that it wouldn't have the U.S. Air Force RFP requirements, many of which caused huge problems and setbacks for the Shuttle program even before it got going.
The real practical use of nuclear rockets will be in interplanetary space. The room to use them is there, as is the need. Even a modest but steady thrust that can be maintained for days or even weeks is going to have some tremendous benefit instead of monster initial rocket thrusts you get from chemical rockets that end suddenly.
In addition, once the spacecraft is safely in space itself, almost any kind of nuclear contamination event is going to be easily dealt with, and except for very localized problems trying to deal with the issue is not going to "harm" the environment in any way at all. Idiots who are opposed to nuclear space are simply misinformed. They are idiots because they have never really studied the issue, nor really understand what the general environment is like in interplanetary space.
LEO nuclear reactors are a little more dangerous, but not substantially so.
Sounds like they need to bring out "Big Gemini"
on
NASA's Shuttle Plans
·
· Score: 1
In case you never have heard about this program, this is the Big Gemini or Gemini II Project that was proposed to NASA right at the end of the original Gemini missions. You can also see the "real thing" that was built as part of a full-scale mock-up.
There was another "failed" hold over from the pre-Shuttle days called Apollo II as well, that was essentially a beefed up Apollo capsule that could hold up to seven passengers and crew. Basically the current crew load of the Shuttle. Trying to build on the Apollo technology, it would also incorporate some of the ideas that also developed from Gemini. Keep in mind that despite the fact that the Apollo capsules went to the moon later, the Gemini program was in some ways a more advanced program than the Apollo system... in part because it was built with newer technologies.
One of the reasons why Gemini is getting another look today is because the standard two-person version can fit on top of the Falcon V, and make a base design for an orbital vehicle. The Falcon V is going to be man-rated, and a bit cheaper than the Russians are able to put somebody up into orbit. Plus (for those that care), SpaceX is an American company, avoiding the political issues of going to Russia for at least American companies or tourists.
A beefed up Falcon V (Falcon X?) could in theory be able to launch seven astronauts at once. Certainly at a substantial fraction of the price for a single shuttle launch, and to the same orbit.
No, the parent poster was mistaken. Planetary movements can and are measured to incredible degrees of accuracy with iterative algorithms doing the calculations. Otherwise the Cassini space probe would never have arrived on time and in the right place to drop a probe into Titan. Talk about some precision flying there. It arrived +/- about 1km based on earlier calculations before it left the Earth (with some minor course corrections enroute because the rocket engines really aren't that accurate).
To calculate the effects of all of the planets on the rotation velocity of the Earth, however, is going to be considerably more complicated and require much higher accuracy. That was the point I was trying to make earlier.
The Heisenberg postulate has nothing to do with three-body problems... at least at the masses involved with objects in the Solar System. I guess at some point really far down quantum gravitons will play a role, but when dealing with 10^12 kg for even small objects in the solar system, you generally don't have to worry about them. Relativity on the other hand does apply, and you do have relativistic effects due to large gravity wells (like the Sun).
Three-body problems are so notorious because the calculation precision is incredibly difficult. The best models that have been developed for celestial mechanics (and used to determine spacecraft trajectories around the solar system) are essentially a time loop algorithm that applies vector equations to all of the bodies of the solar system over time in discrete intervals (usually seconds or hours... sometimes days), recalculates how gravity affects all of the components (with simplifications usually for just the Sun and Jupiter, although other major planets are sometimes thrown in) and adjusts the new velocity vectors and position. These models can, however, be quite accurate and have been done for centuries (really!). Computers have made them much easier to implement.
What makes these models work is mainly because space is so empty, and planets tend to be point sources as far as gravitational attraction is usually concerned. All of the objects in the solar system do affect each other, however, and sometimes in substantial ways.
BTW, such models are commonly used now, otherwise you wouldn't be able to predict events like a solar eclipse to any precision. Getting a spacecraft to Mars or Jupiter would be practically impossible without such models.
One area I forgot to mention in my post was that movement of magma within the Earth also has a significant effect. Witness the discussion about the Indian Ocean tsuami and its effects on the rotation speed of the Earth (it speed up the Earth by a fraction of a second per day due to the Earth contracting... like an ice skater pulling in her arms). These seemingly random effect also have significant impact on trying to calculate the accuracy of how fast over time the Earth will be spinning, hence a correlation between UTC and terrestrial time that needs constant adjustment.
Anybody that writes software for such a precise timing system should use TAI instead of UTC. Essentially the same thing, TAI is always going to have 60 second minutes. Any external displays of time are simply TAI + UTC leap seconds, but that is only for external consumption. Any internal time keeping measurements should then only have to deal with a specific "epoch" that can start on any arbitrary time period, and that is something that is application specific.
When logging for legal purposes, on the otherhand, knowing precisely the UTC time is important. With few exceptions though, I think you would find most internal clocks for most computers to only be accurate to +/- 5 minues, if even that good. With those kind of errors, it makes no difference if you even deal with a leap second.
On a historical basis and from what all subsequent time keeping systems have been based upon, is precisely the observations at Greenwich. GMT is still measured, and is partially responsible for determining when a leap second should be issued or not.
The problem with GMT is that the length of a second can vary, and current physical measurements of time require a much more precise definition of a second. This is the #1 reason for moving to UTC. BTW, I love this definition from the USNO website on time systems:
Julian Day Number is a count of days elapsed since Greenwich mean noon on 1 January 4713 B.C., Julian proleptic calendar. The Julian Date is the Julian day number followed by the fraction of the day elapsed since the preceding noon.
What about atomic clocks in the year 4713 B.C.? And why that date in particular? (There is a good reason, but it just seems a little weird.) What is awsome is that the information can even be calculated back that far so accurately.
The reason why leap seconds are a big mess is because the Universe is a big mess. You can't get chronographers (or is that chronologists?) to predict when the next leap second is going to occur or why the Earth seems to be keeping such good time right now.
The Earth's rotation is influenced not just by the Moon, but by the Sun and all of the rest of the planets, and to some degree by other stars and objects in the rest of the Universe. In theory (related to determinism, but also has quantum effects at some point) if you knew the mass of all of the objects in the Solar System and where they were to incredible precision, you might be able to come up with a mathmatical model that would be highly accurate in regards to leap seconds.
And to top it off, with all of the motions of all of these other objects affecting the Earth, it makes for very irregular adjustments. In all told, the Earth is a very lousy timepiece for measuring time compared to current time keeping equipment. That wasn't always the case, but it is now.
Don't forget that you can also have a reverse leap second (where some minute only has 59 seconds instead of 61), although one has never been issued so far. That is an event that would really rock a lot of poorly written computer software. No calendar that I've ever see designed has a "reverse leap day" in comparison, although I guess for exotic worlds that may be possible.
The reason why leap days are much less controvercial is because they tend to be predictable. Even so, our calendar is not very accurate in terms of having the Vernal Equinox (the current standard that is attempted to be correlated) always fall on the same day. To do something similar with the calendar that these astronomers are doing with syncronization of the the day to the reckoning of the Earth would require some very irregular Leap day insertions. I believe that the Mayans did exactly that with their calendar, however (which required full-time astronomers to determine the length of the year at the begining of each year... and yes the Mayans had some excellent astronmer/priests.)
What breaks? Stuff written by a %@%#)(*&%# lazy programmer that doesn't understand what time is? This is the same lousy excuse of people that can't get leap years correct or caused the Y2K bug. I had to fix a Y2K bug that was written by a programmer in 1999... you would have thought he would have known better.
If you have to keep a "timestamp" in seconds anyway, it is best to use # of seconds past midnight on some arbitrary date (like 1 Jan 1970) and allow an adjustable "leap second epoch" to be added to tweak the current reckoning of midnight. Unfortunately lazy programmers havn't thought of that, and assumed their knowledge of time from grade school was sufficient... and assumed wrong.
This is an issue of sheer incompetance and something easily automated as long as you know the subject. It is nothing like trying to do natural language input or predictive algorithms. That takes some genuine brains.
This has everything you mentioned above, plus some very current research, the role of the USNO in the GPS satellite constellation, and even the history of timekeeping in the USA. On the whole an excellent resource to look at if you want to know more about time.
Whenever I setup a new system, I usually drop by their "what time is it" to set the clocks on systems (especially if I don't want to download or enable a nettime client). It will get you the correct time +/- 30 seconds with the web interface, which is as good or better than most casual users really care to get it anyway. Usually far more accurate than most people's watches as well.
I would agree that if a $1 B X-Prize type competition were set up to develop an alternative Shuttle program (at this point NASA's proposed budget for each flight) it would be money much better spent than trying to keep this fleet of dinosaurs running. And as NASA has pointed out so cleary here, they havn't even learned their lessons from the past.
I've said it before and I'll say it again: The time for NASA to shine has passed. The agency is in need of serious restructuring or complete irrelevance. They have an impressive history, but their current track record is abyssmal.
In short, fix the problems NASA, or get out of the way. This half-hearted effort to keep the shuttles running is a total disappointment.
That is nothing. I think Zero G Adventures already has a deal with Vivid Entertainment to make a film. Of course that isn't quite the same as going into orbit, but that is only a matter of time. Just keep going to your usual websites for more details when the film actually gets made, and no doubt there will be some sort of posting here on/. when it does.
I don't think you read though the article. (You know... RTFA!)
In this case the Russians are going to send up the trans-lunar rocket in a different "booster" that would have to be strapped onto presumably a Soyuz capsule in a docking manuver. The Russians are actually pretty good at this sort of thing, although "refueling in orbit" is still a new trick.
Basically they don't have to build any new launch platforms as all of the components will come up from existing launch vehicles. The only real problem is trying to coordinate multiple launches at the same time, and try to get to the ISS as a transfer station to lunar orbit. with all of the gear to do in space assembly. Indeed this gives an actual use to the ISS rather than a $50 billion (yes, billion) hunk of U.S. taxpayer paid-for hunk of metal that will make an instant enemy if it ever deorbited.
BTW, this was one of the schemes that was proposed by Von Braun in the early 1960's, but was passed by to do the direct shot system of Apollo, due to the shorter time span to get the whole thing up and running. In this case, however, the ISS is already built, so that critical stage has already been completed. The ISS also has the capability to expand if necessary, so additional crew quarters and extra modules in theory could even be added if the demand increased substantially.
Frankly I think it is a brilliant plan, and for only $100 million this is cheap. The current flight by Discovery is about $1.5 billion, and I would rather see the entire crew of the Discovery get some serious trans-lunar experience than keep repeating the business of hauling trash from the ISS (its current mission).
Since you have chosen to no use the "no karma bonus" to post the above message, I choose not to either to get this point across.
There is a huge difference between a government and a random idiot who thinks he can steal all of my money. A government has fixed assets and can't go anywhere. They also have a "reputation" to uphold, and a history to compare against.
If you want to talk about governments, try Nigeria, Zaire (or is that Congo...or is that People's Republic of the Congo... or is that the Free African Republic... or is that???), or even some of the Carribian "republics". Even a "stable" government like the Dominican Republic doesn't honor its debts when a new government is elected (I know, I was involved with a $500,000 project and that government... we were worried we wouldn't get the job finished before the new government came to power).
In this case it was just some random/. user, and we all know how "honest" each and every person on here would be if they were offered $100 million as a slush fund with only a web URL as the only point of contact. Totally trustworth, and going through PayPal? Really. And you want to compare that to the U.S. government?
Somethings a government is totally the wrong approach to deal with, but something government sponsored or at least government regulated, with a high bond requirment and other licensing issues dealth with including certified assurances of money being placed in escrow. I saw none of that. Now show me how you would do any better, or is this just some stupid chance to make a dig at a government that you hate and don't desire any protection on behalf of.
Frankly for myself, if the proverbial "shit hits the fan", I would rather have the US government or the Russian government backing me up, or at least my country. Preferably both of them. I certainly would not want to be on the wrong side against either or both of them, nor especially in the "neutral zone" between either one if they get pissed at each other.
China, while having the ability to send astronauts to orbit (don't get me on the taikonaut issue), don't have the man-rated heavy lift experience that the Russians have. The ESA doesn't even have manned spaceflight experience at all, unless you count the joint ESA/NASA flights of the Space Shuttle... and even that was largly American infrastructure that put them into orbit.
So far, in order to pull something like this off, it is either the Russians or NASA. 10 years from now that may be a totally different story, but there is a huge leap to go from sub-orbital (like Scaled Composites) to orbit, and an even larger leap to go from LEO to lunar orbit.
The neat thing is that going from LEO to lunar orbit is not nearly as complex as going from sub-orbital to LEO. And lunar orbits to lunar landings are not too much more complex either.
I guess I need to count exactly how many people have actually orbited around the moon.
The following are the flights and crew of who made it to the "far" side of the moon.
Apollo 8: Frank Borman James Lovell, Jr. William Anders
Apollo 9: (was only in Earth Orbit to test the Lunar Module...never made it to the moon)
Apollo 10: Eugene Cernan John Young Thomas Stafford
Apollo 11: Neil Armstrong Michael Collins Edwin Aldrin Jr.
Apollo 12: Charles Conrad, Jr. Richard Gordon, Jr. Alan Bean
Apollo 13: James Lovell Jr. (2nd trip) John Swigert Jr. Fred Haise Jr.
Apollo 14: Alan B. Shepard, Jr. Stuart A. Roosa Edgar D. Mitchell
Apollo 15: David R. Scott James B. Irwin Alfred M. Worden
Apollo 16: John Young (2nd trip) Thomas Mattingly Charles Duke, Jr.
Apollo 17: Eugene Cernan (2nd trip) Ronald Evans Harrison Schmitt
So in all told, 24 people have made it to do a similar kind of trip, and 12 have made it to the surface of the moon. And 3 lucky bastards made it to the moon twice in their lives (although Jim Lovell didn't have too much fun on that 2nd trip).
Yeah, a trip to the moon through the Russians would still make you one of the first 50 people to get so far away from the Earth in all of history.
Actually, this is a neat idea on the whole. A time-limited lotto that was run by some formal lottery organization (not some random joe internet user like yourself... I'm sorry, but I have know idea who you are at the moment) where if not enough money was raised to cover the costs of the launch would then be donated to some "worthy" cause, or even a more conventional lotto drawing would occur + a trip to space (to orbit if $10 million were raised, or on Virgin Galactic if > $1 million were raised) if not enough money were raised through something like this.
Lotteries of this nature were proposed by many early Science Fiction authors, including Heinlein and Asimov. The trick is to figure out how to tell the scam artists from legitimate operations.
Without the Air Force RFP requirements and a hard look at what worked and what didn't work on the Shuttle, I think it would have made a tremendous impact. Possibly with the early retirement (in the early 1990's instead of now) of the Columbia, Atlantis, and Discovery if it turned out to be a better vehicle. Certainly a safer vehicle could have been built.
Unfortunately for government operations (and for many large corporations for that matter), it is easier to get enough replacement parts to build 5 vehicles than it is to simple get a single one from a purchase order. That can be a jeep, truck, golf cart, or in the case a shuttle. It doesn't really matter. It looks like that is exactly what NASA did here.
Slashdot Mirror
Again, you think this isn't being done, in regards to a particular article having citations being used as where the original source material was posted from? I do it all of the time, and some of the better articles have both a bibliography and even footnotes. When there is an editorial dispute, the citations are especially used to prove factual quality. There are even facilities within the MediaWiki software to merely put down an ISBN number and that will link you to pages like Amazon.com or Barnes & Noble so you can look up the dead-tree citation and get a copy of the book yourself, or even look it up in your local library. So even a random citation for just about anything can usually be found, and found quickly except for unpublished sources. And yes, there are mechanisms to directly tie these references to the poster directly who added both the citation and the content of the article.
The trust rating is more social, as in the fact you get used to the same set of authors and after awhile you get used to who is likely to mess things up and who does a solid job of fixing things up in an outstanding manner. You also have access to the edit history of each author that you suspect may be doing some damage, and there are even structures within Wikipedia to deal with problem users. Outright trolls (the GNAA has moved into Wikipedia lately) are dealt with harshly, to the point their IP addresses are banned from even participating. There are some problems with doing that, but even the "innocent" people who get burned due to trolls are allowed to appeal their case of banning.
In the case of Wikinews, citations are considered "essential" and are grounds for deletions if you don't provide a direct news source (or in that case don't clearly identify that you are the original journalist creating the account as an eyewitness). If you want to see how each reference is thouroughally checked and identified, try to get in and edit a Wikinews article, particularly on a front-page article or even a developing story. Try to introduce a bogus "fact" without a citation reference, or even "make up" a reference. I promise you that it will be culled almost immediately.
Wikipedia articles take a little more time before the vetting occurs, but it does occur as well in even some of the most obscure articles that I've seen. Almost every subject you can imagine has at least a few people that really are knowledgeable about that subject, and getting away with introducing outright BS (like the Moon is made of cheese or that Bill Clinton was the first astronaut in orbit) is going to be edited out over time. Wacked out UFO conspirists generally don't get much of a chance to promote their theories, unless the article is specifically about one of their theories... and even then the citation issues still hold.
It appears that you think the trust metric applying to both the content entry and encouraging citations should be more rigerous, and required, even put into the software of the contributors putting in the content. I would dare you to find even a peer reviewed scientific paper that has been published which has that thourough of a review where each sentance has been put under that kind of scrutiny. I know of PhD dissertations that should have had that kind of review that didn't (where you would expect that kind of microscopic review process).
While certainly things could be improved, I find that the current review process is very healthy. I've even written extensive articles myself and when I've made even minor typos simply due to the huge amount of content I've added, they have been corrected by other readers and contributors. And that is on very technical subjects where the typo would never have been caught by a spell checker. I did review the change and discovered that I made a mistake... again a part of the review process.
There already is a sort of "windowed" review area that each user has available to him/herself. You can select each article you want to "watch", and even remove articles from you "watch list". If there is something you have been working on and somebody makes a change, you can run over and see what those changes are right away.
This "Window" is extensiable for up to 7 days for you to review anything that you are interested in how it has changed. I use it all of the time... usually to introduce myself to new users or in fighting arguments on topics I'm interested in. Most of the content of Wikipedia is covered by at least one or more of these "watched" pages by some user, so it tends to keep vandalism down just through that system alone. If you don't like the changes to the article, you can always "revert" the changes, or get into a discussion about why you didn't like the changes, together with a datestamp to the exact change and by whom did the change.
As far as formal peer review to "publish" changes, that is in part what Jimmy Wales is talking about with the "Wikipedia 1.0". They want to push articles into a higher caliber of quality and make only those articles that may be of high quality to make that next step of being "published"... with active peer review to accept or reject the nomination.
That is already there. Look at the history tab for any article, and you can get an edit by edit view of each article, who made the change, and (usually) why. It will show diffs between versions of the article, and point out who is the screwup and who did the deliberate vandalism. If you have a known vandal, you can even scan through just their edits and try to undo their damage... even if the article has changed since they've done the damage.
You also have the "option" of linking via URL to only a specific version of a page, if you want to link to just that article.
Images are a bit more problematic as the software treats multimedia content a bit different from text. There still is a history log of the changes to media files, and you can "go back in time" to earlier versions, and even "revert" to that earlier version if you don't like how the image has been changed. There does need to be a link between a historical article version and the historical media, but that is an issue for a later release of the software underlying Wikipedia.
Basically, you can do exactly what you are talking about right now.
The problem you have with a citation list is how do you provide it? A web crawler through all of the internet? How do you deal with "citations" of dead tree content? That is an impractical solution. A citation list of articles that link to an article within Wikipedia is already present and running right now, and that is a fair metric that is often quoted. There is even a ranked list of "links" to articles that don't even exist! (The link exists, the article it links to doesn't, however.)
As far as "web of trust" is concerned, that is something that is proposed in a future version of the MediaWiki software that is behind Wikipedia. The rating systems are being proposed. If you want to join in the discussion you are certainly welcome. The decisions on how to accomplish this havn't been decided yet.
As has been pointed out elsewhere, other sources of knowledge (news websites, slashdot, printed books, newspapers, etc.) also have trust problems with them as well... and people decrying that certain media outlets are less than honest to their subscribers/viewers/readers/listeners. I would argue that Wikipedia even now does a better job than most of these other information sources, and it can be pointed out some substantial biases are found in more traditional information sources.
Of course there are "trusted" information sources that we all use every day, and of that I agree that we all have an internal "BS" detector. Unfortunately it doesn't always work the way we want it to work in every case.
The Air Force got their hands into the mess right at the beginning. The Shuttle together with what later became the ISS was supposed to replace the Air Force Manned Observation Laboratory.
The U.S. Air Force, back in the late 1960's, had this ambitious militarization of space program where they would have a permanent manned space station with Air Force officers manning weapons that could be launched or "observed" from space. A total of about eight astronauts were actually selected and went through quite a bit of training and design work. This was seperate and distinct from the NASA astronaut selection program (more civilian in nature...but did allow selection of military personnel). These astronauts reported directly the the Secretary of the Air Force, not the NASA heirarchy.
Later these astronauts were moved over to NASA without having to go through a normal selection process, but many of the Air Force mandates were also "rolled" into NASA projects. This was done at the end of the Johnson administration.
One of the things that the Air Force did was to build a complete second launch facility at Santa Barbars, California at the Vandenburg Air Force Base. The intention here was to be able to launch the Space Shuttle into polar orbit. While the launch facilities were built, the Shuttle has never been launched from this facility. The runway strip at this base was also design to handle an emergency landing of a shuttle, although Edwards AFB is comparatively nearby and would be considered a prime recovery area for a polar orbit as well.
There were other screwy things the Air Force did to mess with the design parameters of the Shuttle, and there were several classified missions the Air Force flew using the Space Shuttle that for some reason had to have the current characteristics that are in the Shuttle program. While some details of those mission have been declassified (including what astronauts flew on them), there are some missions that are still very black in terms of what really happened.
In short, yes, the Air Force had a big hand in what happened with the Space Shuttle, and the design would have been quite a bit different had NASA alone been involved with the design process.
I would love to find a solid reference to this. I've read a number of reports about how simply silly the whole business of Freon refrigerants has come about and the only legitimate "environmental" reason for not using Freon is simply one:
The patent on Freon ran out and DuPont Chemicals needed an alternative they could continue to make more money on. The environment of their board room wasn't plush enough and needed environmental change. Believe it or not I've actually seen that reason used in an environmental impact statement (for killing other projects).
At least if you look at when the patent on Freon ran out, it is very coincidental as to when all of the "Ozone hole" stories started to surface regarding the ill effects of Freon and other chlorine-based aerosols in the upper atmosphere.
Yes, I've read and even seen demonstrated the effects of Freon on rarified ozone... don't flame about that. Freon was an incredibly safe chemical in a large number of ways that its replacements havn't really been all that useful toward... and if it is killing people you can point to (like the Shuttle astronauts), that is more than enough reason to think it was a poor idea to switch.
The Saturn V with Apollo capsule was 370 feet tall... the original purpose. Actually there was an even larger rocket design that was planned, so yeah, 500 feet does seem to sound correct.
Indeed, here are the "official" dimensions:
http://science.ksc.nasa.gov/facilities/vab.html
The rooftop is over 525 feet tall. They may have to "cut" a new door frame on the exit in order to accomodate such a large beast, and possibly rework the primary cranes, but it could be done. A large rocket wouldn't force a major redesign of the facility or force a new building to be built.
Yes, the Shuttle is a complex machine. I've heard that over and over again each time I see a shuttle launch program on TV, or when astronauts talk about it.
That is precisely the problem... not the ice damage or the configuration. Any engineer from any discipline can tell you that each time you add a new part or increase the complexity of a machine that you are likely to screw it up.
At their heart, a rocket is a very simple machine. You throw "stuff" out the back end of the rocket, and as fast as you possibly can. The trick that modern rocket builders need to deal with is that to achieve orbital velocities you need to have a rocket that sends "stuff" out so quickly that it reaches insane temperatures, and even incredible temperature differences (going from -200C to 4000C in less than 10 seconds for the fuel). You also need to have a "fuel pump" that can effectively pour a controlled but huge volume of fuel at constant (or at least consistant) pressure. Indeed, it is the design of an efficient turbo pump to push fuel into the combustion chamber that most rocket scientists spend their time. And where most of the complexity comes in. Dealing with cryogenic fuels also has some additional problems (in the case of the shuttle).
The trick to reduce errors and failures is that you have to simplify the idea and approach. One solution to this issue is that if you have an assembly line of rockets being built, you have other incentives to simplify... mainly because it gets cheaper to build them in the first place when there are fewer complex parts.
The current fleet of Space Shuttles are each hand-crafted and in many ways unique craft each in their own right. They each have a very interesting history, and in some areas you can't "mix" and "match" or change parts (although sometimes NASA tries real hard in this prespect).
As you also pointed out, there were problems with the tile system. When it was first proposed, even before STS-1 with Columbia, there were quite a few complaints about this heat-protection system. There was at the time a "wait and see" standard mantra coming from NASA, to see just how effective it was. And indeed it has been quite successful in a number of ways, but it has proven to be far too fragile for repeated flights.
The other thing that a redesigned Shuttle would have in its favor is that it wouldn't have the U.S. Air Force RFP requirements, many of which caused huge problems and setbacks for the Shuttle program even before it got going.
The real practical use of nuclear rockets will be in interplanetary space. The room to use them is there, as is the need. Even a modest but steady thrust that can be maintained for days or even weeks is going to have some tremendous benefit instead of monster initial rocket thrusts you get from chemical rockets that end suddenly.
In addition, once the spacecraft is safely in space itself, almost any kind of nuclear contamination event is going to be easily dealt with, and except for very localized problems trying to deal with the issue is not going to "harm" the environment in any way at all. Idiots who are opposed to nuclear space are simply misinformed. They are idiots because they have never really studied the issue, nor really understand what the general environment is like in interplanetary space.
LEO nuclear reactors are a little more dangerous, but not substantially so.
In case you never have heard about this program, this is the Big Gemini or Gemini II Project that was proposed to NASA right at the end of the original Gemini missions. You can also see the "real thing" that was built as part of a full-scale mock-up.
There was another "failed" hold over from the pre-Shuttle days called Apollo II as well, that was essentially a beefed up Apollo capsule that could hold up to seven passengers and crew. Basically the current crew load of the Shuttle. Trying to build on the Apollo technology, it would also incorporate some of the ideas that also developed from Gemini. Keep in mind that despite the fact that the Apollo capsules went to the moon later, the Gemini program was in some ways a more advanced program than the Apollo system... in part because it was built with newer technologies.
One of the reasons why Gemini is getting another look today is because the standard two-person version can fit on top of the Falcon V, and make a base design for an orbital vehicle. The Falcon V is going to be man-rated, and a bit cheaper than the Russians are able to put somebody up into orbit. Plus (for those that care), SpaceX is an American company, avoiding the political issues of going to Russia for at least American companies or tourists.
A beefed up Falcon V (Falcon X?) could in theory be able to launch seven astronauts at once. Certainly at a substantial fraction of the price for a single shuttle launch, and to the same orbit.
No, the parent poster was mistaken. Planetary movements can and are measured to incredible degrees of accuracy with iterative algorithms doing the calculations. Otherwise the Cassini space probe would never have arrived on time and in the right place to drop a probe into Titan. Talk about some precision flying there. It arrived +/- about 1km based on earlier calculations before it left the Earth (with some minor course corrections enroute because the rocket engines really aren't that accurate).
To calculate the effects of all of the planets on the rotation velocity of the Earth, however, is going to be considerably more complicated and require much higher accuracy. That was the point I was trying to make earlier.
The Heisenberg postulate has nothing to do with three-body problems... at least at the masses involved with objects in the Solar System. I guess at some point really far down quantum gravitons will play a role, but when dealing with 10^12 kg for even small objects in the solar system, you generally don't have to worry about them. Relativity on the other hand does apply, and you do have relativistic effects due to large gravity wells (like the Sun).
Three-body problems are so notorious because the calculation precision is incredibly difficult. The best models that have been developed for celestial mechanics (and used to determine spacecraft trajectories around the solar system) are essentially a time loop algorithm that applies vector equations to all of the bodies of the solar system over time in discrete intervals (usually seconds or hours... sometimes days), recalculates how gravity affects all of the components (with simplifications usually for just the Sun and Jupiter, although other major planets are sometimes thrown in) and adjusts the new velocity vectors and position. These models can, however, be quite accurate and have been done for centuries (really!). Computers have made them much easier to implement.
What makes these models work is mainly because space is so empty, and planets tend to be point sources as far as gravitational attraction is usually concerned. All of the objects in the solar system do affect each other, however, and sometimes in substantial ways.
BTW, such models are commonly used now, otherwise you wouldn't be able to predict events like a solar eclipse to any precision. Getting a spacecraft to Mars or Jupiter would be practically impossible without such models.
One area I forgot to mention in my post was that movement of magma within the Earth also has a significant effect. Witness the discussion about the Indian Ocean tsuami and its effects on the rotation speed of the Earth (it speed up the Earth by a fraction of a second per day due to the Earth contracting... like an ice skater pulling in her arms). These seemingly random effect also have significant impact on trying to calculate the accuracy of how fast over time the Earth will be spinning, hence a correlation between UTC and terrestrial time that needs constant adjustment.
Anybody that writes software for such a precise timing system should use TAI instead of UTC. Essentially the same thing, TAI is always going to have 60 second minutes. Any external displays of time are simply TAI + UTC leap seconds, but that is only for external consumption. Any internal time keeping measurements should then only have to deal with a specific "epoch" that can start on any arbitrary time period, and that is something that is application specific.
When logging for legal purposes, on the otherhand, knowing precisely the UTC time is important. With few exceptions though, I think you would find most internal clocks for most computers to only be accurate to +/- 5 minues, if even that good. With those kind of errors, it makes no difference if you even deal with a leap second.
On a historical basis and from what all subsequent time keeping systems have been based upon, is precisely the observations at Greenwich. GMT is still measured, and is partially responsible for determining when a leap second should be issued or not.
The problem with GMT is that the length of a second can vary, and current physical measurements of time require a much more precise definition of a second. This is the #1 reason for moving to UTC. BTW, I love this definition from the USNO website on time systems:
Julian Day Number is a count of days elapsed since Greenwich mean noon on 1 January 4713 B.C., Julian proleptic calendar. The Julian Date is the Julian day number followed by the fraction of the day elapsed since the preceding noon.
What about atomic clocks in the year 4713 B.C.? And why that date in particular? (There is a good reason, but it just seems a little weird.) What is awsome is that the information can even be calculated back that far so accurately.
The reason why leap seconds are a big mess is because the Universe is a big mess. You can't get chronographers (or is that chronologists?) to predict when the next leap second is going to occur or why the Earth seems to be keeping such good time right now.
The Earth's rotation is influenced not just by the Moon, but by the Sun and all of the rest of the planets, and to some degree by other stars and objects in the rest of the Universe. In theory (related to determinism, but also has quantum effects at some point) if you knew the mass of all of the objects in the Solar System and where they were to incredible precision, you might be able to come up with a mathmatical model that would be highly accurate in regards to leap seconds.
And to top it off, with all of the motions of all of these other objects affecting the Earth, it makes for very irregular adjustments. In all told, the Earth is a very lousy timepiece for measuring time compared to current time keeping equipment. That wasn't always the case, but it is now.
Don't forget that you can also have a reverse leap second (where some minute only has 59 seconds instead of 61), although one has never been issued so far. That is an event that would really rock a lot of poorly written computer software. No calendar that I've ever see designed has a "reverse leap day" in comparison, although I guess for exotic worlds that may be possible.
The reason why leap days are much less controvercial is because they tend to be predictable. Even so, our calendar is not very accurate in terms of having the Vernal Equinox (the current standard that is attempted to be correlated) always fall on the same day. To do something similar with the calendar that these astronomers are doing with syncronization of the the day to the reckoning of the Earth would require some very irregular Leap day insertions. I believe that the Mayans did exactly that with their calendar, however (which required full-time astronomers to determine the length of the year at the begining of each year... and yes the Mayans had some excellent astronmer/priests.)
What breaks? Stuff written by a %@%#)(*&%# lazy programmer that doesn't understand what time is? This is the same lousy excuse of people that can't get leap years correct or caused the Y2K bug. I had to fix a Y2K bug that was written by a programmer in 1999... you would have thought he would have known better.
If you have to keep a "timestamp" in seconds anyway, it is best to use # of seconds past midnight on some arbitrary date (like 1 Jan 1970) and allow an adjustable "leap second epoch" to be added to tweak the current reckoning of midnight. Unfortunately lazy programmers havn't thought of that, and assumed their knowledge of time from grade school was sufficient... and assumed wrong.
This is an issue of sheer incompetance and something easily automated as long as you know the subject. It is nothing like trying to do natural language input or predictive algorithms. That takes some genuine brains.
By far the best resource I've ever seen concerning time and navigation is: http://tycho.usno.navy.mil/
This has everything you mentioned above, plus some very current research, the role of the USNO in the GPS satellite constellation, and even the history of timekeeping in the USA. On the whole an excellent resource to look at if you want to know more about time.
Whenever I setup a new system, I usually drop by their "what time is it" to set the clocks on systems (especially if I don't want to download or enable a nettime client). It will get you the correct time +/- 30 seconds with the web interface, which is as good or better than most casual users really care to get it anyway. Usually far more accurate than most people's watches as well.
I would agree that if a $1 B X-Prize type competition were set up to develop an alternative Shuttle program (at this point NASA's proposed budget for each flight) it would be money much better spent than trying to keep this fleet of dinosaurs running. And as NASA has pointed out so cleary here, they havn't even learned their lessons from the past.
I've said it before and I'll say it again: The time for NASA to shine has passed. The agency is in need of serious restructuring or complete irrelevance. They have an impressive history, but their current track record is abyssmal.
In short, fix the problems NASA, or get out of the way. This half-hearted effort to keep the shuttles running is a total disappointment.
That is nothing. I think Zero G Adventures already has a deal with Vivid Entertainment to make a film. Of course that isn't quite the same as going into orbit, but that is only a matter of time. Just keep going to your usual websites for more details when the film actually gets made, and no doubt there will be some sort of posting here on /. when it does.
I don't think you read though the article. (You know... RTFA!)
In this case the Russians are going to send up the trans-lunar rocket in a different "booster" that would have to be strapped onto presumably a Soyuz capsule in a docking manuver. The Russians are actually pretty good at this sort of thing, although "refueling in orbit" is still a new trick.
Basically they don't have to build any new launch platforms as all of the components will come up from existing launch vehicles. The only real problem is trying to coordinate multiple launches at the same time, and try to get to the ISS as a transfer station to lunar orbit. with all of the gear to do in space assembly. Indeed this gives an actual use to the ISS rather than a $50 billion (yes, billion) hunk of U.S. taxpayer paid-for hunk of metal that will make an instant enemy if it ever deorbited.
BTW, this was one of the schemes that was proposed by Von Braun in the early 1960's, but was passed by to do the direct shot system of Apollo, due to the shorter time span to get the whole thing up and running. In this case, however, the ISS is already built, so that critical stage has already been completed. The ISS also has the capability to expand if necessary, so additional crew quarters and extra modules in theory could even be added if the demand increased substantially.
Frankly I think it is a brilliant plan, and for only $100 million this is cheap. The current flight by Discovery is about $1.5 billion, and I would rather see the entire crew of the Discovery get some serious trans-lunar experience than keep repeating the business of hauling trash from the ISS (its current mission).
Since you have chosen to no use the "no karma bonus" to post the above message, I choose not to either to get this point across.
/. user, and we all know how "honest" each and every person on here would be if they were offered $100 million as a slush fund with only a web URL as the only point of contact. Totally trustworth, and going through PayPal? Really. And you want to compare that to the U.S. government?
There is a huge difference between a government and a random idiot who thinks he can steal all of my money. A government has fixed assets and can't go anywhere. They also have a "reputation" to uphold, and a history to compare against.
If you want to talk about governments, try Nigeria, Zaire (or is that Congo...or is that People's Republic of the Congo... or is that the Free African Republic... or is that???), or even some of the Carribian "republics". Even a "stable" government like the Dominican Republic doesn't honor its debts when a new government is elected (I know, I was involved with a $500,000 project and that government... we were worried we wouldn't get the job finished before the new government came to power).
In this case it was just some random
Somethings a government is totally the wrong approach to deal with, but something government sponsored or at least government regulated, with a high bond requirment and other licensing issues dealth with including certified assurances of money being placed in escrow. I saw none of that. Now show me how you would do any better, or is this just some stupid chance to make a dig at a government that you hate and don't desire any protection on behalf of.
Frankly for myself, if the proverbial "shit hits the fan", I would rather have the US government or the Russian government backing me up, or at least my country. Preferably both of them. I certainly would not want to be on the wrong side against either or both of them, nor especially in the "neutral zone" between either one if they get pissed at each other.
China, while having the ability to send astronauts to orbit (don't get me on the taikonaut issue), don't have the man-rated heavy lift experience that the Russians have. The ESA doesn't even have manned spaceflight experience at all, unless you count the joint ESA/NASA flights of the Space Shuttle... and even that was largly American infrastructure that put them into orbit.
So far, in order to pull something like this off, it is either the Russians or NASA. 10 years from now that may be a totally different story, but there is a huge leap to go from sub-orbital (like Scaled Composites) to orbit, and an even larger leap to go from LEO to lunar orbit.
The neat thing is that going from LEO to lunar orbit is not nearly as complex as going from sub-orbital to LEO. And lunar orbits to lunar landings are not too much more complex either.
I guess I need to count exactly how many people have actually orbited around the moon.
The following are the flights and crew of who made it to the "far" side of the moon.
Apollo 8:
Frank Borman
James Lovell, Jr.
William Anders
Apollo 9: (was only in Earth Orbit to test the Lunar Module...never made it to the moon)
Apollo 10:
Eugene Cernan
John Young
Thomas Stafford
Apollo 11:
Neil Armstrong
Michael Collins
Edwin Aldrin Jr.
Apollo 12:
Charles Conrad, Jr.
Richard Gordon, Jr.
Alan Bean
Apollo 13:
James Lovell Jr. (2nd trip)
John Swigert Jr.
Fred Haise Jr.
Apollo 14:
Alan B. Shepard, Jr.
Stuart A. Roosa
Edgar D. Mitchell
Apollo 15:
David R. Scott
James B. Irwin
Alfred M. Worden
Apollo 16:
John Young (2nd trip)
Thomas Mattingly
Charles Duke, Jr.
Apollo 17:
Eugene Cernan (2nd trip)
Ronald Evans
Harrison Schmitt
So in all told, 24 people have made it to do a similar kind of trip, and 12 have made it to the surface of the moon. And 3 lucky bastards made it to the moon twice in their lives (although Jim Lovell didn't have too much fun on that 2nd trip).
Yeah, a trip to the moon through the Russians would still make you one of the first 50 people to get so far away from the Earth in all of history.
Actually, this is a neat idea on the whole. A time-limited lotto that was run by some formal lottery organization (not some random joe internet user like yourself... I'm sorry, but I have know idea who you are at the moment) where if not enough money was raised to cover the costs of the launch would then be donated to some "worthy" cause, or even a more conventional lotto drawing would occur + a trip to space (to orbit if $10 million were raised, or on Virgin Galactic if > $1 million were raised) if not enough money were raised through something like this.
Lotteries of this nature were proposed by many early Science Fiction authors, including Heinlein and Asimov. The trick is to figure out how to tell the scam artists from legitimate operations.
Without the Air Force RFP requirements and a hard look at what worked and what didn't work on the Shuttle, I think it would have made a tremendous impact. Possibly with the early retirement (in the early 1990's instead of now) of the Columbia, Atlantis, and Discovery if it turned out to be a better vehicle. Certainly a safer vehicle could have been built.
Unfortunately for government operations (and for many large corporations for that matter), it is easier to get enough replacement parts to build 5 vehicles than it is to simple get a single one from a purchase order. That can be a jeep, truck, golf cart, or in the case a shuttle. It doesn't really matter. It looks like that is exactly what NASA did here.