Expendables ar significantly cheaper at current flight rates. In order to be cost-effective a reusable launch vehicle needs to have a a very high flight right (thus providing a large number of laynches over which to amortize the development and manufacturing costs). The shuttle has two problems when it comes to achieving those high flight rates:
There isn't presently a market for that many flights per year
The shuttle design isn't capable of supporting enough launches per year even if the market existed: it's simply not a good design in terms of operability and turn-around time
Trust me, it's been going on for way more than the last week. Somehow Piquepaille has managed to average 1 story every 2-3 days for the past 6 months or more. I don't know how he does it. Kickbacks to the/. editors maybe?
Is there any reason to believe JWST/NGST will cost significantly less than hubble? So lets estimate $US1-1.5billion all up. How much does a servicing mission cost to hubble (ignoring the fact that JWST will be at L2)? Something like a couple hundred million? I don't know the actual number, but that's what's in my head. (Do you know it? I'd like to know) The point: I'm *highly* skeptical of your "we just build a new one" claim. Prove it!
Shuttle launches run to around US$500M (the actual cost is unclear, since it's never costed on a per-launch basis) - or at least they used to before all this extra safety stuff was added in. Assuming that NASA does actually manage to get shuttle operational again (which isn't guaranteed) the cost of an individual launch will probably be even higher than it used to be. Then you have to throw in the cost of the replacement hardware.
According to this the JWST will cost US$824.8M. That appears to include launch costs (Ariane V, so probably ~$100M), and operations (for 5-10 years). A large chunk of the cost of the telescope itself will be non-recurring engineering (i.e. design work). Assuming a build-to-print replacement telescope, you could probably do a replacement (with launch costs) for around $400M or less. So, less than a shuttle mission (neglecting the whole L2 issue), and no lives risked.
It still doesn't invalidate my point that 20 years is not particularly "old" for a telescope. Especially when it cost $US1.5billion.
By way of calibration: the Mars Exploration Rover mission cost just shy of a $1B, and will be lucky to last 2 years, let alone 20. Space isn't cheap.
With regard to repairing Hubble, there's only so much stuff you can repair/replace (without actually replacing the whole thing) before it succumbs to old age. It's not clear that it's cost-effective to do another servicing mission - you may save the gyros, only to have other stuff fail. Space is not a benign environment. The cumulative total radiation dose is slowly chewing thorugh HST's electronics (although I believe the last servicing mission replaced the onboard computer, other electronic devices onboard are still the originals), the micrometeoroid background is eating at its structure, the batteries are nearing the end of their cycle life, and the thermal system is slowly degrading as the optical properties of the HST exterior change due to micrometeroid strikes and solar UV. Let it die.
Incidentally, I'm no fan of the Bush Mars plan. I just think that all the noise over Hubble is driven as much by partisan politics as it is by scientific, engineering, and cost considerations.
The X-33 design was doomed to failure from the get-go. It was a risky design that relied on a lot of high-tech stuff that hadn't been fully developed at program inception. The non-payload mass grew with every design revision, while the payload mass shrank. The cost was excessive. It should have been cancelled a long time ago. I'm no fan of Bush, but he made the right move in killing X-33.
BTW, it wan't the Delta Clipper that "crashed" (the Clipper was never built) it was the DC-X prototype. It didn't so much crash, as fall over after a minor propellant explosion caused by NASA incompetence (this occurred after NASA forced the program to be transferred from BMDO to NASA) blew away one of the landing legs.
The wing features allow the Shuttle to be reusable.
Actually, the wings aren't there for reusability - there're plenty of designs for reusable LVs that don't have wings, e.g. the Delta Clipper, Phoenix, or Kistler K-1. The wings are there because NASA needed USAF support to get the shuttle funded, and the USAF mandated that the launch vehicle have a fairly large cross-range capability (i.e. the ability to deviate significantly from the initial entry trajectory to either side). The wings were necessary in order to meet this cross-range requirement. The capability was mandated in order to allow the USAF to carry out missions to retrieve Soviet satellites from orbit - something the shuttle never ended up being used for.
Actually, drag is a perfectly valid term when talking about the orbits that the shuttle operates in. The neutral atmosphere at that altitude is much thinner than down at sea level, but still dense enough to cause significant drag (why do you think the ISS needs to be reboosted every few months) as well as aerodynamically generated disturbance torques that (in the case of the shuttle) require propellant usage to correct. Throw in the fact that the wings are dead weight that costs propellant during orbital maneuvers, and create a larger moment of inertia during attitude maneuvers, and you start to wonder why we'd want wings at all (the answer, BTW, is nothing to do with reusability or efficiency, it's cross-range capability).
Yeah, that was kind of the point the story submitter was trying to make when they put "as open as MP3" in quotes, and made the crack about a royalty-bearing, pseudo-open universal 3D format. Even if you're not going to RTFA you could at least RTF/.S.
The academic literature search is pretty much dead these days - there's just so much stuff going on in the world that it's well nigh impossible to be completely up to date on your field. There're entire communities of researchers that have no idea what other, similar groups are up to.
I'm a new convert to the Mac religion, after about 7 years of Linux at home and Windows at work, and many years of DOS and Windows before that. I just picked up my first Mac (a Powerbook) recently. The first thing I noticed when I opened the box was the power adapter. Yes, the power adapter. It impressed the hell out of me, mostly because of what it boded for the design of the rest of the system. When something as seemingly mundane as the power adapter displays the elegance of design, and thought given user convenience, that the Apple power adapter does, you can pretty much count on the computer itself being a joy to use. And it has been so far. I definitely understand why Apple has so many devoted fans now.
People who work for government bureaucracies are at least ostensibly working for the good of the country
Which unfortunately means that they can do all sorts of otherwise unacceptable things simply by invoking the fact that it's "for the national good". The folks working for the government bureacracies in the Stalinist USSR certainly seemed to be doing a lot of "good" for the country. I realize that the US is not like that (yet). My point is that what the bureacracy is "ostensibly" for often has little bearing on what it actually does.
Governments also have to follow stricter laws that serve to at least slightly protect citizens
[snort] Governments set those "stricter" laws. And they can discard them if they choose - see the PATRIOT Act for a fine example of that in action.
I'm not saying that corporations are less likely to perpetrate evil than governments. I'm just saying that governments aren't necessarily any better than corporations.
The fallacy that you refer to doesn't apply to solar panels in quite the same way as it does to ethanol. The question needs to be something more like "what is the ratio of (power produced per sq ft)*(lifetime of a sq ft)/(energy required to create square foot)?" So long as that ratio is greater than 1 there will be a net gain in energy.
Or may the copyright holder (in this case Novell) decide that the GPL licensing terms no longer apply, and since they own the work completely, suddenly forbid *any* GPL versions at all? Even those that existed just before the "point of departure"?
Short answer: No.
Longer answer: Novell (or any other copyright owner for that matter) owns the copyright, which is what allows them to decide which license to release a product under. However, if you obtain a GPLed product from a copyright owner, they have granted you the rights laid out in the GPL, such as the right to freely redistribute, and the right to make modifications (provided said mods are released GPL as well). That license cannot be retroactively cancelled. All that Novell could do is refuse to release all future versions of Evo under the GPL. At which point the GPLed version of Evo would probably fork into a separate project. That's the beauty of GPLed code - once it's out there, it's out there. Doesn't matter if the company producing the code goes belly-up, or decides to stop providing updates, or whatever. The code is still there, and can still be worked with.
Actually, if you stop to read their course descriptions you 'll se the following (this just from the first quarter):
LA 120 Written and Spoken Communications I
Students strengthen their composition and oral presentation skills. Students examine the purpose, structure, logic, and language of expository writing. Students explore and apply appropriate skills for writing and public speaking, including the principles of rhetoric. Students learn the speech, composition, and delivery techniques needed to prepare for a variety of effective presentations.
LA 125 Collaborative and Interpersonal Communications
Students develop collaborative skills for successful interpersonal interactions and group work. Students learn and apply principles related to interpersonal communications, group dynamics, leadership and followership, benefits and caveats of group work, and the collaborative group life cycle.
Not to say that I think this degree has any merit at all. But you are wrong about the fact that they don't teach "communication skills".
Perhaps Im wrong and this cariculum will teach excelent data structure usage, and algorithim analysis and AI and compiler design and low level architecture. But at this point i kind of doubt it.
Looking at their curriculum course descriptions, I'd say that your doubts are well founded. Looks like a trade school with a few classes in logic and discrete math thrown in. I don't see much on software engineering (aside from lip service to "the complete software life cycle"), let alone any actual computer science.
I bet you think Dolly the sheep (the clone) stole the sole of the orignial, depriving it of a life, too. Because, er, you're dumb.
Hmmmm... there's something fishy about your comment. I say that solely because it seems unlikely that Dolly could steal her Mommy's sole, let alone walk a mile in her shoes, since they are physically distinct entities. Yes, I believe that's the heart (and soul) of the matter. Would you care to take your foot out of your mouth now?;-)
Which will be fine of the creators of said digital products agree to having their products copied. Much as I may disagree with content creators licensing choices, I will defend their right to choose those licenses - because that right is the only thing that prevents good licenses like the GPL from being so much hot air. If you don't like the license, don't use the product. It's that simple.
I think that what the parent was getting at is that GNOME should be independent of Linux, not just independent of a given distribution. There are other OSes out there than Linux you know. Some of 'em even use GNOME.
It's all about the price point. Several rich guys paying $10K to rent the stadium is going to net you more in recouped costs than no rich guys renting the stadium because you're asking too much for the rental.
Secondly, the station is already bought and paid for. That funding was justified on the basis of the supposed benefits of the station, and didn't account for any dollars recouped through tourist flights. So any money from the tourists is just gravy at this point.
Thirdly, the tourist flights were responsible for partially subsidizing the Russian launches. Otherwise, there wouldn't have been any launch. Then there'd be no one on the station, and your expensive taxpayer "investment" would be going to waste.
Earth-Moon L-1? Riiiiight
on
Soyuz To The Moon?
·
· Score: 3, Informative
Interesting to note that in this slide they allude to the possibility of making some kind of permament "depot" at the Earth-Moon L-1. Which makes great PR, but also leads me to wonder just how much real analysis has gone into their mission concepts.
Libration point mission are hard. Manned libration point missions - if we ever do one - would be harder, since they tend to be much more susceptible to last-minute changes in trajectory. Then add the complications of trying to do proximity maneuvers, let alone rendezvous-and-docking, in such a complex dynamic environment (the cutting edge in L-point research right now is formation flying - not close maneuvers, but just trying to maintain any kind of coordinated trajectory between multiple spacecraft). Finally, throw in the fact that the Earth-Moon libration points are tenuous at best, with dynamics that are seriously warped by the Sun's gravity (libration "points" are an artifact of three-body dynamics, such as Earth-Moon-Spacecraft), and you have a recipe for a severe difficulties or a serious cost explosion. Not to mention the propellant costs incurred by attempting to station-keep for any appreciable period of time in the vicinity of their "depot". As I said, it makes me wonder about the quality and/or depth of their analysis...
I'll second that motion. The sheer quantity of Piquepaille articles is astounding - something like 1 every 2-3 days (does he give kickbacks to the/. eds?). And as you say, every single one includes links to his blog. At least Google has the courtesy to place the ads in a separate screen location, instead of embedding them directly in their "product".
They switched off the deliberate corruption of the civilian GPS signal. However, military GPS receivers still have better accuracy, because they operte on two frequencies instead of just one. The second frequency allows them to model errors due to atmospheric signal delays, and then subtract those errors out. The next-gen GPS satellites (GPS IIF and GPS III) are supposed to add a second civilian signal to allow civilians to achieve more accurate positioning. However IIRC the military will still be more accurate, as they play other games with the signal.
This has the potential to fracture EFF and PubPat too...
I'd like to think that the folks at EFF understand that the long-term damage accrued by going against their principles in order to stop RFID will far outweigh the short-term gains that may occur if they are actually able to prevent RFID from being adopted. The ends do not justify the means - especially when there's a very strong likelihood that the same means will come back to bite you at a later date.
Slashdot Mirror
Trust me, it's been going on for way more than the last week. Somehow Piquepaille has managed to average 1 story every 2-3 days for the past 6 months or more. I don't know how he does it. Kickbacks to the /. editors maybe?
Shuttle launches run to around US$500M (the actual cost is unclear, since it's never costed on a per-launch basis) - or at least they used to before all this extra safety stuff was added in. Assuming that NASA does actually manage to get shuttle operational again (which isn't guaranteed) the cost of an individual launch will probably be even higher than it used to be. Then you have to throw in the cost of the replacement hardware.
According to this the JWST will cost US$824.8M. That appears to include launch costs (Ariane V, so probably ~$100M), and operations (for 5-10 years). A large chunk of the cost of the telescope itself will be non-recurring engineering (i.e. design work). Assuming a build-to-print replacement telescope, you could probably do a replacement (with launch costs) for around $400M or less. So, less than a shuttle mission (neglecting the whole L2 issue), and no lives risked.
It still doesn't invalidate my point that 20 years is not particularly "old" for a telescope. Especially when it cost $US1.5billion.
By way of calibration: the Mars Exploration Rover mission cost just shy of a $1B, and will be lucky to last 2 years, let alone 20. Space isn't cheap.
With regard to repairing Hubble, there's only so much stuff you can repair/replace (without actually replacing the whole thing) before it succumbs to old age. It's not clear that it's cost-effective to do another servicing mission - you may save the gyros, only to have other stuff fail. Space is not a benign environment. The cumulative total radiation dose is slowly chewing thorugh HST's electronics (although I believe the last servicing mission replaced the onboard computer, other electronic devices onboard are still the originals), the micrometeoroid background is eating at its structure, the batteries are nearing the end of their cycle life, and the thermal system is slowly degrading as the optical properties of the HST exterior change due to micrometeroid strikes and solar UV. Let it die.
Incidentally, I'm no fan of the Bush Mars plan. I just think that all the noise over Hubble is driven as much by partisan politics as it is by scientific, engineering, and cost considerations.
BTW, it wan't the Delta Clipper that "crashed" (the Clipper was never built) it was the DC-X prototype. It didn't so much crash, as fall over after a minor propellant explosion caused by NASA incompetence (this occurred after NASA forced the program to be transferred from BMDO to NASA) blew away one of the landing legs.
Actually, the wings aren't there for reusability - there're plenty of designs for reusable LVs that don't have wings, e.g. the Delta Clipper, Phoenix, or Kistler K-1. The wings are there because NASA needed USAF support to get the shuttle funded, and the USAF mandated that the launch vehicle have a fairly large cross-range capability (i.e. the ability to deviate significantly from the initial entry trajectory to either side). The wings were necessary in order to meet this cross-range requirement. The capability was mandated in order to allow the USAF to carry out missions to retrieve Soviet satellites from orbit - something the shuttle never ended up being used for.
Actually, drag is a perfectly valid term when talking about the orbits that the shuttle operates in. The neutral atmosphere at that altitude is much thinner than down at sea level, but still dense enough to cause significant drag (why do you think the ISS needs to be reboosted every few months) as well as aerodynamically generated disturbance torques that (in the case of the shuttle) require propellant usage to correct. Throw in the fact that the wings are dead weight that costs propellant during orbital maneuvers, and create a larger moment of inertia during attitude maneuvers, and you start to wonder why we'd want wings at all (the answer, BTW, is nothing to do with reusability or efficiency, it's cross-range capability).
Yeah, that was kind of the point the story submitter was trying to make when they put "as open as MP3" in quotes, and made the crack about a royalty-bearing, pseudo-open universal 3D format. Even if you're not going to RTFA you could at least RTF/.S.
The academic literature search is pretty much dead these days - there's just so much stuff going on in the world that it's well nigh impossible to be completely up to date on your field. There're entire communities of researchers that have no idea what other, similar groups are up to.
I'm a new convert to the Mac religion, after about 7 years of Linux at home and Windows at work, and many years of DOS and Windows before that. I just picked up my first Mac (a Powerbook) recently. The first thing I noticed when I opened the box was the power adapter. Yes, the power adapter. It impressed the hell out of me, mostly because of what it boded for the design of the rest of the system. When something as seemingly mundane as the power adapter displays the elegance of design, and thought given user convenience, that the Apple power adapter does, you can pretty much count on the computer itself being a joy to use. And it has been so far. I definitely understand why Apple has so many devoted fans now.
Which unfortunately means that they can do all sorts of otherwise unacceptable things simply by invoking the fact that it's "for the national good". The folks working for the government bureacracies in the Stalinist USSR certainly seemed to be doing a lot of "good" for the country. I realize that the US is not like that (yet). My point is that what the bureacracy is "ostensibly" for often has little bearing on what it actually does.
Governments also have to follow stricter laws that serve to at least slightly protect citizens
[snort] Governments set those "stricter" laws. And they can discard them if they choose - see the PATRIOT Act for a fine example of that in action.
I'm not saying that corporations are less likely to perpetrate evil than governments. I'm just saying that governments aren't necessarily any better than corporations.
The fallacy that you refer to doesn't apply to solar panels in quite the same way as it does to ethanol. The question needs to be something more like "what is the ratio of (power produced per sq ft)*(lifetime of a sq ft)/(energy required to create square foot)?" So long as that ratio is greater than 1 there will be a net gain in energy.
Bureaucracies are just as self-perpetuating as corporations, so there's not necessarily anything to be gained by having a public prison system.
Short answer: No.
Longer answer: Novell (or any other copyright owner for that matter) owns the copyright, which is what allows them to decide which license to release a product under. However, if you obtain a GPLed product from a copyright owner, they have granted you the rights laid out in the GPL, such as the right to freely redistribute, and the right to make modifications (provided said mods are released GPL as well). That license cannot be retroactively cancelled. All that Novell could do is refuse to release all future versions of Evo under the GPL. At which point the GPLed version of Evo would probably fork into a separate project. That's the beauty of GPLed code - once it's out there, it's out there. Doesn't matter if the company producing the code goes belly-up, or decides to stop providing updates, or whatever. The code is still there, and can still be worked with.
The situations you describe sound a lot more like computer engineering than computer science to me.
Looking at their curriculum course descriptions, I'd say that your doubts are well founded. Looks like a trade school with a few classes in logic and discrete math thrown in. I don't see much on software engineering (aside from lip service to "the complete software life cycle"), let alone any actual computer science.
Hmmmm... there's something fishy about your comment. I say that solely because it seems unlikely that Dolly could steal her Mommy's sole, let alone walk a mile in her shoes, since they are physically distinct entities. Yes, I believe that's the heart (and soul) of the matter. Would you care to take your foot out of your mouth now? ;-)
BTW, I think you need to s/sole/soul/g
Which will be fine of the creators of said digital products agree to having their products copied. Much as I may disagree with content creators licensing choices, I will defend their right to choose those licenses - because that right is the only thing that prevents good licenses like the GPL from being so much hot air. If you don't like the license, don't use the product. It's that simple.
I think that what the parent was getting at is that GNOME should be independent of Linux, not just independent of a given distribution. There are other OSes out there than Linux you know. Some of 'em even use GNOME.
Secondly, the station is already bought and paid for. That funding was justified on the basis of the supposed benefits of the station, and didn't account for any dollars recouped through tourist flights. So any money from the tourists is just gravy at this point.
Thirdly, the tourist flights were responsible for partially subsidizing the Russian launches. Otherwise, there wouldn't have been any launch. Then there'd be no one on the station, and your expensive taxpayer "investment" would be going to waste.
Libration point mission are hard. Manned libration point missions - if we ever do one - would be harder, since they tend to be much more susceptible to last-minute changes in trajectory. Then add the complications of trying to do proximity maneuvers, let alone rendezvous-and-docking, in such a complex dynamic environment (the cutting edge in L-point research right now is formation flying - not close maneuvers, but just trying to maintain any kind of coordinated trajectory between multiple spacecraft). Finally, throw in the fact that the Earth-Moon libration points are tenuous at best, with dynamics that are seriously warped by the Sun's gravity (libration "points" are an artifact of three-body dynamics, such as Earth-Moon-Spacecraft), and you have a recipe for a severe difficulties or a serious cost explosion. Not to mention the propellant costs incurred by attempting to station-keep for any appreciable period of time in the vicinity of their "depot". As I said, it makes me wonder about the quality and/or depth of their analysis...
I'll second that motion. The sheer quantity of Piquepaille articles is astounding - something like 1 every 2-3 days (does he give kickbacks to the /. eds?). And as you say, every single one includes links to his blog. At least Google has the courtesy to place the ads in a separate screen location, instead of embedding them directly in their "product".
They switched off the deliberate corruption of the civilian GPS signal. However, military GPS receivers still have better accuracy, because they operte on two frequencies instead of just one. The second frequency allows them to model errors due to atmospheric signal delays, and then subtract those errors out. The next-gen GPS satellites (GPS IIF and GPS III) are supposed to add a second civilian signal to allow civilians to achieve more accurate positioning. However IIRC the military will still be more accurate, as they play other games with the signal.
Yeah, that was kind of my point. I just said it in a much more verbose way the first time around.
I'd like to think that the folks at EFF understand that the long-term damage accrued by going against their principles in order to stop RFID will far outweigh the short-term gains that may occur if they are actually able to prevent RFID from being adopted. The ends do not justify the means - especially when there's a very strong likelihood that the same means will come back to bite you at a later date.