Doubts About Future GPS Reliability

loped_index writes "IT Week reports that the U.S. GPS system is in a delicate state, and that full coverage could be lost if older satellites fail faster than the current rate. From the article: 'The system relies on a network of satellites, which cannot be repaired once launched and have a limited lifespan. Sixteen of the present 28 satellites were built to last seven and a half years, but are now between eight and 14 years old. Twenty-four satellites are required for full coverage.'"

Comments

Oh dear

[Britissippi]

We'll never find them when they fall then..?

Always good to know...

[Nom du Keyboard]

Always good to know I'll have something more to worry about this weekend. I was afraid I was going to run short.

Looks like I'm stuck here at work

[Anonymous Coward]

How will I get home without my GPS box?

Time to look backward for a backup

[geomon]

I guess we shouldn't have jettisoned WBS so quickly.

Re:Time to look backward for a backup

[jdigriz]

What do you mean? I was listening to WWV at 10 Mhz last Sunday. "At the tone, the time wil be 23 hours, three minutes, Coordinated Universal Time Beeee-booooop, tick, tick, tick, tick" I was using it to test an el-cheapo JWIN Shortwave radio, and the reception was poor, but audible.

Re:Time to look backward for a backup

[Anonymous Coward]

Your comment might relevent if:
A. Ground-based radio time was no longer available -- it is
B. Ground-based radio timekeeping independently useful in radionavigation -- it's not

Re:Time to look backward for a backup

[geomon]

Pardon. I must be more specific when dealing with ACs.

Your comment might relevent if:
A. Ground-based radio time was no longer available -- it is
B. Ground-based radio timekeeping independently useful in radionavigation -- it's not

The system I work on no longer uses WBS as a timing device.

So much for /. comraderie. More like a knife to the back.

sounds like good target practice

[Anonymous Coward]

for future missile defense systems.

EU's Galileo

[innerewut]

So maybe the US will stop its attemps to prevent the European Galileo...

Re:EU's Galileo

[garcia]

So maybe the US will stop its attemps to prevent the European Galileo...

That's the only reason for this article. To put negative spin on the US-based system and give positive PR for Galileo.

Move along.

Re:EU's Galileo

[Anonymous Coward]

Several US firms - and the US governement are active in the development of Galileo as even the most basic search will turn up. However, the big difference comes down to the desire by several of the EU backers to piggyback their encrypted signal in the same space as the GPS encrypted signal. You can imagine anyone getting upset when a newcomer decides to ride on the same signal area (i.e. BPL and hamms).

Re:EU's Galileo

[Poltras]

The article was there to mention the short unreliability of GPS; promoting a system that is 4-5 years (for serious and public applications) from now isn't the point. As long as I am concerned, it will be iron solid and a good successor to GPS (better range, more precise measures, etc).

Re:EU's Galileo

[hey!]

Another bit of embarassing US diplomatic incompetence.

We so obviously didn't want Europe to have an independent positioning system, that anybody with half a brain would have to wonder if there were some ulterior motive, especially since we were at the same time thumping our chest about the irrelevance of the UN, and baiting key EU members with jibes about "Old Europe". Rumsfeld couldn't have made himself clearer if he banged on the table with his shoe.

For such a bunch of Bible Thumbers, they certainly don't seem to be aware of Proverbs 15:1 -- "A soft answer turneth away wrath: but grievous words stir up anger."

Re:EU's Galileo

[Anonymous Coward]

Several US firms - and the US governement are active in the development of Galileo as even the most basic search will turn up.

Yes, and those same searches will reveal the reason that the US government is active - because they want the ability to unilaterally disable it if they so choose.

Re:EU's Galileo

[theLOUDroom]

So maybe the US will stop its attemps to prevent the European Galileo...


Actually, it looks like this whole thing may be just misinformation to drum up support for Galileo.

The satellites are lasting LONGER than expected, and we have plenty of spares. It appears the article may also have the number of necessary satellites wrong.

As someone else has pointed out:
Bonnor said launches of new satellites are "only just keeping up" with current losses of around two satellites per year.

So we HAVE SPARES and we're REPLACING THE SPARES AS WE USE THEM. Sounds like it's working just dandy.

Re:EU's Galileo

[Anonymous Coward]

Let me get this straight. You nearly praise the European nations and call the US incompetent, despite the EU-related solution is over 4 years off, not to mention have questionable delivery systems themselves.

You take the word of a UK individual who, like folks anywhere in the world, gives talks to promote their opinion that are largely unsubstantiated unless they are privy to manufacturing data and known defects which allow him to, within reason, truly call into question satellite failure en masse. I doubt a UK RAF person will know the intimate details of the satellites. What we do know is their failure rate to date.

It's not like nothing is being done with this problem and the problem is not unknown or being ignored; the US has known about this for some time now. Our delivery systems have had problems and huge delays (space shuttle, rockets blowing up), yet we still have been managing to replace the birds that do croak. And are replacing them next with longer lasting birds.

You overlook the fact that many satellite systems are overbuilt and typically do last well beyond their expected lifetimes. Not all do, but a good number have (classic would be the Voyager; one still is running rather well). Until these systems start dropping rapidly faster than we can replace them, I don't see the issue. 4 of them could croak now, and you'd still get accurate info. If a 5th dies, we have one waiting to be launched already and would likely ramp up replacement schedules. If a 6th dies before all that, it depends on WHICH it dies and WHERE you are to determine if it may affect you directly.

You trust this same Old World Europe at the expense of the US, yet look at the recent examples of them deliberately trying and "warning" regarding the domain system (which is something that could have occurred at any time prior anyways).

You use this as an opportunity attack ad hominum US diplomacy, when that has little to do with satellite failure and more to do with their tactics of trying to get their own system (Galileo) up.

I'm not a bible thumper. And yet even I know the problems with the proverb you quote and at the very least, it points to lack of real world experience on your part. Anytime I've spoken softly, the other person being receptive listened, but they weren't, I've watched people get pushed around and one person punched. Anytime I've yelled at someone, they overwhelmingly back down or at the very least snap from the focus, if temporarily, from the object of their violence. I just choose to yell when the situation merits it and that's not often, only when I've or another has been physically threatened and do so then to try to avoid or head off fights.

You attack the right, making no distinction between it and the religious right, just to be critical of the US, meanwhile the EU (multiple nations too) kisses the ass of some of the most suppressive fascist and religious states in the world. Freakin hypocrite. Anytime the Old World gets involved in diplomacy, nothing of substance positive comes about to improve the world order. It's not like the EU is doing this out of the goodness of their hearts either; they want the markets, a price cut, the membership, the money just as well if not more so than the US counterparts.

There will always be those who read a story about "US companies do [questionable or suspected evil activity]" and say, damn, it's all the US's fault, never asking or researching the EU or any other nation's track record on that same matter. But if the EU ballerinas in and bends over before doing a twirl and says "all will be okay, we're here", you're more inclined to take their word for it.

You want to doubt and disagree with the US government? Good. I'm with you. But don't think that because you do and can that the US government is worse than some other half-baked government out there; that's a totally different set of standards and questions which you certainly have not addressed yourself.

Re:EU's Galileo

[myc_lykaon]

So we HAVE SPARES and we're REPLACING THE SPARES AS WE USE THEM. Sounds like it's working just dandy.

I think you are omitting the critical point of the article. The satellites have onboard redundant systems that already have been used - there are no more onboard backup systems to use in the current orbiting fleet. The implication is that the failure rate is going to accelerate beyond the replacement rate real soon now.

Re:EU's Galileo

[theLOUDroom]

The implication is that the failure rate is going to accelerate beyond the replacement rate real soon now.

So if that *actually* happens they'll increase the replacement rate. Are we now also worried that the US is suddenly only going to be capable of two satellite launches per year?

My point is that this is all silly sensationalism. If the failure rate doubles, no big deal, we send up a few more. The system would still have 100% uptime.

For the GPS system to actually become "unreliable", failure rates would have to increase by orders of magnitude. There is no data presented to suggest such an abrupt change might take place.

Re:EU's Galileo

[Anonymous Coward]

Sorry, but this is Slashdot. Everything the US does is bad, incompetent and evil - facts be damned.

Re:EU's Galileo

[defago]

Someone should mod the parent up.

What several posts fail to understand (e.g., grand parent or a few posts in parallel threads) is that the failure rate of a system is not constant over time. In fact, what any introductory book on system reliability teaches is that systems reliability follows a curve with a high initial failure rate that does down very steeply (initial defects), followed by a low and flat period (period of exploitation/amortization), and after that a steep increase (wear out).
See also Wikipedia on failure rate and especially the typical bath tub curve.

What the article implies is that the satellite were designed and built so that the increased failure rate due to wear out would not occur before seven 1/2 years, but that this period has passed, and that the system is showing signs that the satelittes are indeed wearing out and that the failure rate will begin to increase very signficantly soon. Thus, being able to "just keep up" with the current failure rate will not be sufficient to prevent the system from collapsing.

Based on the assumptions (wear out signs; amortizing period; no replacement plan) made by the author of the article, his conclusions are unquestionably valid. On the other hand, the counter argument that:
"we have been able to cope with the current failure rate, therefore we will continue to do so"
is flawed because it is based on the wrong assumption that the failure rate of systems is constant.

I am not trying to enter into the politcal side of this discussion, and I agree that the author of the article may have is own motives, but this is simply not relevant to the logic of his argumentation.

Re:EU's Galileo

[Anonymous Coward]

Thus, being able to "just keep up" with the current failure rate will not be sufficient to prevent the system from collapsing.

I deny the premise that the U.S. can only "just keep up" with the posited failure rate.

The U.S. had the capability to establish the network in the early 1980s, and has had the cabability to replace every satellite launched into the network prior to 1989. Source. The U.S. has just recently launched a more capabable replacement satellite as part of a continuing program of maintenance/upgrade launches. Notably, the GPS network was not established through the use of the space shuttle.

Therefore both the grandparent and yourself bear the burden of showing how U.S. satellite launch capabilities have degraded over the last 25 years to the point where the system is irreplaceable. Until then, the logic of his argumentation is b*llsh*t.

Re:EU's Galileo

[addbo]

Does NASA have it in their budget for more than two satellites a year to launch?

Considering the announced cuts to 300 engineers at JPL... how much does a launch cost?

I guess having 5 satellites fail consecutively in a short enough span of time so that replacements don't get put up might be a bit far fetched then again... just hopefully they keep up those launches =)

Still I wouldn't mind another GPS alternative like Galileo up there ...

Addbo

Re:EU's Galileo

[theLOUDroom]

Thus, being able to "just keep up" with the current failure rate will not be sufficient to prevent the system from collapsing.

But the implication that we're only able to just keep up is false.

We're only launching that number of satellites per year because that's how many we need to provide adequate redundancy, not because it's the best we can do. We could send up more, but it would be a waste of money.

What several posts fail to understand (e.g., grand parent or a few posts in parallel threads) is that the failure rate of a system is not constant over time

I understand this concept, but what you're failing to properly acknowedge is that:
A) The system is redundant
B) The failure rate to needs to increase by orders of magnitude in order to outpace our ability to replace satellites.
I highly doubt that the stastical data supports such claims.


Go ahead fit the standard function to the availible data form the GPS satellites the have already failed. I bet it's going to agree with the course of action the the US is taking. Why? Because they can do the same math you can. As a matter of fact, I be they have even better data they don't publish.

I am not trying to enter into the politcal side of this discussion, and I agree that the author of the article may have is own motives, but this is simply not relevant to the logic of his argumentation.

There are gaping holes in his logic. Is it more likely that he's:
A) incompetent
or
B) pushing an adgenda?

Re:EU's Galileo

[clodney]

GPS is funded by the military, so they are launched by the Air Force, not NASA. I know nothing about the budget of either, but I would be surprised if the Air Force was unable to afford 2 launches a year - or even 6 or 7 if the failure rate kicks up.

Re:EU's Galileo

[sch1sm]

A similar article I read a couple of years ago claimed only 8 were needed system to sustain global coverage.

Re:EU's Galileo

[Anonymous Coward]

Um...do you have any idea how many commercial/military sattelites are in space right now?

Re:EU's Galileo

[quax]

But don't think that because you do and can that the US government is worse than some other half-baked government out there.

Sorry, but I think this speaks of lack of real world experience in international settings on your part. The US winner take all election system can produce some really nasty outliers when it comes to the quality of your government. BTW I mean the whole selection process - just imagine McCaine winning the 2000 primaries.

In the EU all member nations need to compromise to get anything done. This process certainly squashes all brilliance but it also quite reliably squashes complete and utter idiocy. And guess what, because the EU only moves by compromise the government that yells the loudest hardly ever wins. It is the ones that can moderate compromises the best that end up with the most influence.

Re:EU's Galileo

[Anonymous Coward]

Which is why the EU accomplishes little on the world stage of substance and proves the poster's point exactly. The EU prefers compromise to the point of a near complete reduction of their effectiveness as a player in world governance to having to deal with the conflicts that inevitably arise from actively pursuing a policy on how the world should behave (like the US does).

It is also telling that the various facets of EU's ruling elite - in government, in governing bodies, etc - have begun a campaign of overtly attempting to sway world opinion through dire warnings blared and amplified through the world media. Actively affecting the internal politics of another country by directly influencing its citenzry rather than conduction relations through government officials is subversion, an act of war generally not pursued by supposed allies.

Re:EU's Galileo

[drooling-dog]

Oh, Lordy... I was wondering how far down the usual nationalistic dick-wagging was going to start. I hardly had to touch the scrollbar.

Re:EU's Galileo

[quax]

Do you mean kind of what your government tried recently in order to influence EU media?

Lucky you, that we do not take this very serious. No, in my view that was really stupid on part of the Bush administration, but it certainly was not an act of war.

But then again in your world view I probably may as well be one of those foreign agents trying to influence the /. crowd, so why would you believe anything I write anyway.

Please wrap your head a bit tighter with your tin foil, after all the EU Galileo satellites are clearly out to get you.

Boy, it really is people like you that are obviously so far divorced from reality that make the world fear (for) the US.

Re:EU's Galileo

[surprise_audit]

We're only launching that number of satellites per year because that's how many we need to provide adequate redundancy, not because it's the best we can do. We could send up more, but it would be a waste of money.

Just as long as we can build and launch new satellites if the rate of loss increases. How long does it take to build the satellites and launchers?? I imagine there's something like an assembly line for these things - can they turn out 16 on short notice??

Re:EU's Galileo

[mosb1000]

Apparently you can't tell the difference between some half-baked defense department plan and official government policy. The defense department comes up with a lot of bone-headed ideas, that's why we don't let them make all the decisions.

Military people just don't think right sometimes, I'd doubt the military commanders of rest of the worlds armies make better judgment calls on this sort of matter. What else would you expect from someone whose job is to resolve problems by force? It's just par for the course I'm afraid. It's as a great american once said "war is to important to be left to the generals."

Re:EU's Galileo

[Fred_A]

It's as a great american once said "war is to important to be left to the generals."

Yes. Right. Except that the quote you're looking for is "La guerre est une affaire trop sérieuse pour être confiée à des militaires" (War is too serious a matter to be left to the military) and that the author is Georges Clemenceau (1841-1929). Damn, and he was a leftist too (that would be a commie to you). I wasn't aware he was a great american though... He probably wasn't aware of it either.

Re:EU's Galileo

[hey!]

Let me get this straight. You nearly praise the European nations and call the US incompetent, despite the EU-related solution is over 4 years off, not to mention have questionable delivery systems themselves.

Nope. You don't get this straight. I didn't praise the EU, but I wouldn't be ashamed of it if I did.

I didn't call the US incompetent. I called the Administration conduct of US diplomacy incomptent.

You take the word of a UK individual who, like folks anywhere in the world, gives talks to promote their opinion

I'm not taking anybody poster's word on the relevant facts, I'm going by the stories that have been reported in the press. Granted that's not perfect, but better than dredging opinions up out of my predjudices.

You overlook the fact that many satellite systems are overbuilt and typically do last well beyond their expected lifetimes.

Never mentioned this at all. My position is that if the EU wants to build their own system, that's they have every right to do so. If we don't want them to build one, we have to persuade them not to.

I'm not a bible thumper. And yet even I know the problems with the proverb you quote and at the very least, it points to lack of real world experience on your part.


Or perhaps experience that doesn't match yours.

Anytime I've spoken softly, the other person being receptive listened, but they weren't, I've watched people get pushed around and one person punched. Anytime I've yelled at someone, they overwhelmingly back down or at the very least snap from the focus, if temporarily, from the object of their violence.

Yes, people do want to humour somebody who is acting like a nut. But then what happens?

You attack the right, making no distinction between it and the religious right, just to be critical of the US, meanwhile the EU (multiple nations too) kisses the ass of some of the most suppressive fascist and religious states in the world.

I did not attack the right. I called the Administration a bunch of Bible Thumpers. I do not as a rule call religious people or conservative religious people bible thumpers. I've had many an enjoyable and civil discussion with conservative religious people, such as my friend the pastor of the evangelical church in my town. "Bible Thumper" carries with it the implied hypocrisy, I never made the connection to relgious conservatives at all. That was you.

Anytime the Old World gets involved in diplomacy, nothing of substance positive comes about to improve the world order

Any time the Old World gets involved in diplomacy, it's to futher their various national interests. Just like us.

You want to doubt and disagree with the US government? Good. I'm with you. But don't think that because you do and can that the US government is worse than some other half-baked government out there; that's a totally different set of standards and questions which you certainly have not addressed yourself.

I think the mania for comparing governments on the scale of stupidity, or atrocities on the scale of wickedness is a waste of time. In any case, it wasn't my point that I disagree with the US government, although I do. It's just that US government doesn't know how to get what it wants.

Re:EU's Galileo

[defago]

I understand this concept, but what you're failing to properly acknowedge is that:
A) The system is redundant
B) The failure rate to needs to increase by orders of magnitude in order to outpace our ability to replace satellites.
I highly doubt that the stastical data supports such claims.


Currently, according to the number stated in the article, the system can tolerate up to 4 defects out of 28, after what the complete coverage is lost. This is not much, but surely enough when the probability of failure of each satellite is low and these probabilities are independent (or can reasonably be assumed to be so), which is more-or-less the case during the random failure period.

The problem is that, when one reaches the wear out period, the satellites cannot be assumed to fail independently, especially if they were all built and put in service at the same time. This means that the failure rate can actually increase by several orders of magnitude in a very brief period.

Besides, even if failures could be assumed to be independent (again, this is purely hypothetical since they are not), then when the inidividual failure probability gets beyond a certain level, a redundancy of 4 out of 28 gives a global failure rate that gets higher than each individual component.

But the implication that we're only able to just keep up is false.

We're only launching that number of satellites per year because that's how many we need to provide adequate redundancy, not because it's the best we can do. We could send up more, but it would be a waste of money.


This simply shows that you have completely missed my point.

As I said, I am not in a position to know about the correctness of the assumptions. My point was about the logic of the argument. I sincerely hope that the US has done their homework and provisioned for a sudden increase in satellite loss when the system reaches the wear out period.
Note though that there are two counter-arguments to your claims:

1. The probability of failure due to wear out cannot possibly be extrapolated from observing the failure probability during the first and second periods, because the causes are completely different.
   
2. Coping up with an increasing failure rate could easily have been thwarted by budget cuts.
   

Before you want to yell at me again, I must add that indeed a sufficient contingency has very possibly been prepared. Besides, I do not reckon that the loss of GPS coverage in some areas for a short period of time (i.e., until some satellites are replaced) is really a critical issue anyway, or is it?


There are gaping holes in his logic. Is it more likely that he's:
A) incompetent
or
B) pushing an adgenda?


No, there may be gaping holes in his assumptions, but not in his logic. Previous posts were attacking his logic rather than his assumption with flawed arguments.

As I said, the fact that he may or may not be pushing an agenda is irrelevant to the discussion. To know whether his conclusions are meaningful, one must check the validity of his assumptions and the logic of his argumentation. Or, to take the opposite viewpoint, the only way to prove that his conclusions are wrong is to invalidate either any one of his assumptions (whether explicit or implicit ones) or show a gap in the logic. Thus far, no actual gap in the logic was validly pointed out. But, the points you raised about the assumptions do actually make sense.

Re:EU's Galileo

[Anonymous Coward]

Or maybe a movie quote ;)

http://www.imdb.com/title/tt0057012/quotes

Re:EU's Galileo

[theLOUDroom]

This means that the failure rate can actually increase by several orders of magnitude in a very brief period.

I'd like to see some real data supporting this offhand statement. Essentially, it's claiming to be able to predict the failure rate better than the guys who actually designed and operate these satellites and have access to more data than you.
I'm not buying it. Also, both common sense and research will point out that the GPS system was put into service over a period of time. There's a pretty large diversity of launch and operational dates up there.

The probability of failure due to wear out cannot possibly be extrapolated from observing the failure probability during the first and second periods, because the causes are completely different.

The oldest satellite up there was launched in 1990. The first GPS satellite was launched in 1978. We have 27 years worth of data, besides the original system calculations that were done.

Coping up with an increasing failure rate could easily have been thwarted by budget cuts.

The GPS system is run by the military, not NASA or the FAA. They have PLENTY of money. The curent cost is around $400 million/year which is nothing for those guys. The overall military budget is more than $400 billion. Proportionately, paying my phone bill is a bigger expense for me than maintaining the GPS system is for these guys.

So, there may be gaping holes in his assumptions, but not in his logic. Previous posts were attacking his logic rather than his assumption with flawed arguments.

It think there are problems with both, but I suspect we're using slightly different meaning for the word logic.

Re:EU's Galileo

[quax]

Look, my link was in response to an AC claiming that the EU was officially doing something that your government on the other hand has actually been looking into to do to us (I am a EU citizen).

Now, if you can provide me with any evidence that the EU ever wasted any of my taxpayer's money on trying to sway public opinion in the US I'd be inclined to listen.

What this AC was spouting was borderline hysterical drivel. That you have nothing better to do than to attack my response to him reinforces my impression that you seem to have a wee bit of a problem with Xenophobia in your country.

Well...

[Sheetrock]

Given that these things are about trying to figure out where you're going, we're close to the point where we don't need satellites for them anyway.

When enough people have them, it'll be just as helpful to have the devices communicate with each other and work out amongst themselves where you're trying to go. Especially when you figure in the possibility of triangulating with cell towers.

It's how the Internet works.

Re:Well...

[merreborn]

we're close to the point where we don't need satellites

That idea falls apart when you're in, say, the alps. Or the sahara. Or most of the planet.

Re:Well...

[camt]

When enough people have them, it'll be just as helpful to have the devices communicate with each other and work out amongst themselves where you're trying to go. Especially when you figure in the possibility of triangulating with cell towers.

Except when there is no cell coverage (which is far from "full coverage") or where there aren't very many other people (tramping/geocaching through remote areas or national parks). Not to mention that would require all those devices to transmit as well as receive, increasing their power requirements significantly.

No thanks.

Re:Well...

[$RANDOMLUSER]

Wasn't it the US Navy that started this whole GPS thing?
Something about knowing where you are and where you're going...

Re:Well...

[Anonymous Coward]

Not to mention that non-government controlled devices could intentionally misrepresent their location.

Re:Well...

[robertjw]

Exactly, GPS was started by the military, with good reason. I can't imagine the military would let the network fail, unless of course they have an alternative in place.

Re:Well...

[scotch]

The US Air Force started GPS and runs it for the benefit of all branches of service as well as civilian use as deemed acceptible.

Re:Well...

[meloneg]

As opposed to the government controlled ones which are known to have misrepresented their location?

Re:Well...

[Detritus]

The U.S. Navy made very substantial contributions to the GPS program. They were the pioneers in satellite-based navigation.

Re:Well...

[Asetilean]

And, last time I checked, it was looking kinda difficult to build stationary cell towers on the ocean, nevermind a pesky lack of demand...

Plus, air traffic is now highly dependant on GPS and most cell antennas aren't aimed up at the sky.

So, for imprecise civilian needs (tell me how to go from here to there), a cell tower based nav system might be fine. But GPS is capable of providing a whole lot more than that.

Re:Well...

[Anonymous Coward]

Insightful?

You must be either;
a) joking
b) completley ignorant to what GPS is used for

They are not about where you are going, not sure what that even means. That are about where you are (which is useful in figuring out how to get to where you are going - if that's what you meant).

95% of GPS users are nowhere near cell towers. Put it this way, if you're within an array of cellular towers then you probably don't need GPS as you are probably smack in the middle of a city!

Re:Well...

[Anonymous Coward]

Yes, as opposed to those.

Re:Well...

[ptbarnett]

Especially when you figure in the possibility of triangulating with cell towers.

The proper functioning of adjacent CDMA cell towers (i.e. Sprint, Verizon in the 1.8 GHz bands, and by US West in the 800 MHz bands) must be synchronized within 10 microseconds to support what is called "soft handoff".

CDMA base stations use the GPS constellation to maintain synchronization. The satellites themselves need precise clock synchronization, and this is exported to GPS receivers.

Re:Well...

[WhiplashII]

The Pacific ocean is 60060700 square miles. The cost of deploying GPS is about $3B, give or take a few orders of magnitude. Assuming that you would need 1 tower per square mile, you could spend $50 per tower - which might actually be possible for something just floating around transmitting a position beacon.

Not necessarily impossible... just unlikely!

Re:Well...

[provolt]

Yeah, the thousands of cell towers that dot the pacific ocean really are a better way to navigate than an old 70's satellite system.

Re:Well...

[Baricom]

First of all, that article says nothing except that selective availability was disabled, meaning the accuracy improves for everybody. There's some veiled tin-foil hat comments about why the government turned it off, but nothing to substantiate the fears.

Second, the GPS constellation never misrepresented the locations of the satellites. They dithered the unscrambled signal from the satellites so receivers couldn't calculate their position as accurately. The article speculates that selective availability may have been disabled because the distance between 30 meters and 100 meters is relatively small, and equipment (missiles?) could easily compensate for the difference.

Re:Well...

[Limecron]

You might be able to BUILD them for $50 a piece. (Though even this is highly unlikely if it's a government project.) But you sure as hell couldn't distribute them across 60060700 square miles for $50 a pop. Forget about monitoring and maintaining them. Also, ground based transmission makes all sorts of other problems.

Re:Well...

[scotch]

Right you are, my friend.

Well that sucks...

[Anonymous Coward]

First the Internet, now this. :/

Re:Well that sucks...

[Anonymous Coward]

That post got an Off-topic mod? Guess the mods don't read slashdot. I thought it was funny.

Original article

Yada yada

[Red Flayer]

Is it just me, or does everyone else also realize we're still capable of launching new satellites into orbit?

Is there a concern about current GPS-enabled devices reading signals from new satellites?

I'd be shocked if there is not money available in the Pentagon Budget, or elswhere, for replacement of needed satellites. Then again, cutting funding of absolutely necessary programs is a great way to dodge real budget cuts... since there will need to be a "special appropriation" to cover the shortfall.

Re:Yada yada

[Osiris Ani]

Indeed, I'm sure I remember reading something somewhere about the US government recently launching newer, more accurate GPS satellites. Of course, what we need these days is more alarmist rhetoric, so I suppose this is apropos.

Re:Yada yada

[Rakishi]

Yeah, why replace them when they're still working fine. That would be a waste of money, extra sats which age and provide little benefit. I mean, unless 5 fail in the time it takes to get a new one up there is no problem. Given that only 2 fail per year I don't see that happening anytime soon.

I mean, come on look at this idiotic statement:
'Bonnor said launches of new satellites are "only just keeping up" with current losses of around two satellites per year.'

What they hell is the US supposed to do, send up more satellites than they lose and waste money keeping up sats when only 24 are needed (+ a few redundant ones)?

Re:Yada yada

[Vellmont]

The concern is that 4 or 5 satellites will all fail in the same year. The current pace of only replacing 2 a year would cause gaps in the GPS coverage. Just because you allocate the funds doesn't mean you get to launch the replacement satellites tommorow to fix the problem. Not knowing much about satellite launch preparation I'm guessing it might take a month or two to get everything ready for launch.

Re:Yada yada

[GileadGreene]

The current replacement rate is designed to slowly phase out existing satellites before they hit their (statistical) expected end-of-life. It's not intended to cope with unexpected (i.e. low probability, such as 4 or 5 satellites dying at once) failures. Nor does it have to. The GPS constellation includes a number of "on-orbit spares" (i.e. spare satellites already in the GPS orbits), which can be used to ensure continuous availability in the face of an unexpected failure. AFAIK the typical scenario is something like:

1. GPS satellite fails
2. On-orbit spare is activated
3. New satellite launched some months later becomes a spare
4. Life goes on

Re:Yada yada

[Vellmont]

Based on what you an others have said this entire article should be marked troll. The most interesting comment was that satellite failure isn't unexpected as the people who manage them get information on the health status of the satellites.

Re:Yada yada

[Anonymous Coward]

Is it just me, or does everyone else also realize we're still capable of launching new satellites into orbit?

For how long though? You've already lost the technology you used to land on the moon. NASA are making major cutbacks. You're in trillions of dollars of debt with no plan to get out of it. And science in the USA is failing rapidly.

At this rate, you'll turn into an unscientific bankrupt theocracy within fifty years. Think you'll still be launching satellites then?

Re:Yada yada

[pr0digy25]

Think you are refering to PPS (Precise Precision System)... military positioning units can pick up another stream (think it's called Y) that is a heck of alot more precise than ol' GPS.

Re:Yada yada

[plover]

GPS satellites transmit two different signals: Precise Positioning Service (PPS) and Standard Positioning Service (SPS). PPS is carried on the dual frequency 'P code' (Precise) and the decryption keys are only present in U.S. military receivers. SPS is carried on the single frequency 'C/A code' (Coarse / Acquisition) used by civilian receivers.

It's incorrect to say the new satellites are "more accurate" -- the satellites themselves are as accurate as they ever were, (unless you're comparing them to the time they still had Selective Availability (SA) turned on. SA was an intentional dithering of the signal intended to deny civilian receivers the highest precision, but SA was turned off in 2000.) The difference is they have raised the transmitter power and added a couple of frequencies. That means that your existing ordinary GPS receivers should deliver more accurate readings, since they will be able to receive better signals from more satellites in more places.

Re:Yada yada

[kriston]

Didn't the advent of WAAS, the Wide-Area Augmentation System, correct the SA error and thus made the SA feature meaningless? Local municipalities started broadcasting correction signals which were used by their WAAS-enabled GPS receivers for 1-meter accuracy even when SA "dithering" was turned on. The system was ingenius--you determine the exact location of a receiver, such as a low-cost PC, then transmit the correcting factor to a local area on a public safety band. The receivers that are WAAS-enabled receive the correcting factor and the GPS signals to provide accuracy as good as GPS with SA turned off.

Essentially, they cracked the system.

Naturally you needed a WAAS transmitter for each local area since the GPS SA resulted in a different error in each area.

Re:Yada yada

[plover]

You just described DGPS, or Differential GPS. DGPS is a local GPS receiver placed in a precisely surveyed location that transmits a "correction" signal on an FM band. Because each station is local, it automatically corrects for local atmospheric conditions.

WAAS is almost the same thing. The difference is that instead of transmitting local corrections on the FM band, the local receivers all uplink the correction data to an FAA satellite located in a geosynchronous orbit above the U.S. This satellite then transmits the correction data in the same band as the GPS signals. That's useful because now your receiver doesn't need a separate radio to tune in the differences as it did with DGPS. It just needs to know how to interpret the WAAS data.

Re:Yada yada

[kriston]

Cool, thanks for the correction!

who pays for this...

[vasanth]

who will be paying for this.. the military, gps receiver manufacturers??

Re:who pays for this...

[Anonymous Coward]

The U.S. Government will pay for the replacements, as they did with the originals.

Re:who pays for this...

[Anonymous Coward]

Correction: The U.S. taxpayers will pay..

Re:who pays for this...

[oringo]

Ha... I'm surprised that this question even came out. Haven't we learnt enough from the past, that no matter who writes the check for those fancy military toys, the tax payer/consumer pays?

Re:who pays for this...

[scotch]

Get a room, you two.

oops (GPS goes out)

[pmike_bauer]

Toto, I don't think we're in Kansas anymore.

Re:oops (GPS goes out)

[geomon]

Toto replies, "How can you tell?"

Of course this is all accomplished by barking very loudly and scampering around.

Re:oops (GPS goes out)

[Anonymous Coward]

Am I just another silly European or was that 'Tonto'?

Re:oops (GPS goes out)

[xenocide2]

Yessir, you are a silly european. Tonto was probably an Indian in the lone ranger, and Toto was a little dog in the Wizard of Oz.

There is only one solution...

[Anonymous Coward]

We MUST hand over ALL CONTROL of the GPS system to the UN, to save it from destroying itself...

Re:There is only one solution...

[amliebsch]

Exactly! Sure, the US invented the system, launched all the satellites, and bears the maintenance cost, but everybody else in the world depends on it, so it's obviously right that the UN control it!

Re:There is only one solution...

[Just Some Guy]

We MUST hand over ALL CONTROL of the GPS system to the UN, to save it from destroying itself...

The first thing that came to mind when I read that was Emacs' "Zippy" mode. I ran M-x yow and got:

I'm RELIGIOUS!! I love a man with a HAIRPIECE!! Equip me with MISSILES!!

Swear to God. I don't know whether to laugh, cry, or lock myself into the panic room.

Re:There is only one solution...

[drsquare]

Yeah, just like the US laid down all the cables and runs all the Internet routers worldwide...

Re:There is only one solution...

[Anonymous Coward]

now THAT is a funny comment. I often say the best thing the US ever did for the rest of the world was GPS. everything else you guys do outside your own borders (including space, but particularly on earth) is a disaster and we'd all have been better off without ya.

now, the irony in your comment is this; there have been thousands of innovations and technologies NOT funded by the US, but after reaching success have been 'hi-jacked' by the US where your government then attempts to enforce regulations and controls on it over the global community.

take, take, take, take, take, take - can you guys ever give?

The REAL irony is whenever you guys do give it is usually a politcal patch to something you messed up (you know, like funding to rebuild Iraq after levelling it to hunt out 1 man).

Re:There is only one solution...

[Anonymous Coward]

Cabling and routing is rather separate in fuction and implementation from DNS. Apparently that is not obvious to someone; just because something's intertwined with overlapping, involved function doesn't make it run by ICANN.

Or are you saying that the EU, China, Iran, and Syria or the like are proposing that taking over the DNS system includes taking over the US controlled responsibility that involves all private intra- and inter-country internet lines and routers (btw, they don't happen to exist in that extent but would for the sake of your argument having any validity whatsoever)?

Something doesn't make sense here.

[Anonymous Coward]

Can somone please explain why these things can't be repaired?

Re:Something doesn't make sense here.

[$RANDOMLUSER]

Um, they're in orbit?

Re:Something doesn't make sense here.

[erikvcl]

If I had any mod points, I'd mod this up as funny. Your post made me laugh.

Not Good

[Paul Pierce]

How will I find my wallet?

I don't care who does what with who

[Anonymous Coward]

As long as they make a backup copy, I'm fine with it.

Re:I don't care who does what with who

[Poltras]

"Only wimps use tape backup: real men just upload their important stuff on ftp, and let the rest of the world mirror it." [Linus B. Torvalds]

They'll launch more

[Frangible]

Everything dies, why is this news? GPS is an important and critical system, it will be maintained through new satellites.

I think I'm still OK

[$RANDOMLUSER]

I use one of these as my GPS.

Re:I think I'm still OK

[stimpleton]

We use these for our navigation system for our vehicle fleet.

Oddly, our accident rate has also gone up recently.

Re:I think I'm still OK

[Anonymous Coward]

You'll be fine if you only move North or South. If you move East West you will have to use another method to calculate your longitude.

Re:I think I'm still OK

[Christopher_G_Lewis]

Make sure you have an acurate time source, like your GPS :-)

Backup Satellites

[g4n0n]

They fail to mention that there are a number of backup satellites sitting up there, waiting to go into the consellation if any fail.

It's cheaper to launch a new one

[grahamsz]

A GPS satelite is relatively inexpensive.

if we were going to send something/someone up to fix repair it, then we could just as easily (probably much more easily) send a new satelite up.

Re:It's cheaper to launch a new one

[jshaped]

wow... did you even read the blurb?
"...which cannot be repaired once launched..."

Re:It's cheaper to launch a new one

[fimbulvetr]

Did you not even read the grandparent's comment? Did you not see that it was a reply to an AC asking " Can somone please explain why these things can't be repaired?"?

Re:It's cheaper to launch a new one

[jshaped]

thank you for pointing that out.
no, i did not read the grandparent.
usually i just look for an 'Re:' in the title of the post,
if not, i assume it's fresh.
i will try to be wiser in the future.
thank you again.

Re:It's cheaper to launch a new one

[Bent Mind]

I agree, but I wonder... Sending something up (even a new satellite) is expensive. Wouldn't it be cheaper to have some kind of in-orbit repair facility? Last I checked, it cost several million just to launch. I wonder if something could be set up that was capable of robotic repair. Maybe have it refuel at the space station as needed, or have it hover in one of the Lagrange points? Just a random thought...

May not be that important, really....

[ip_freely_2000]

"Twenty-four satellites are required for full coverage

As long as the satellites fail over someplace unimportant like Europe, why should we care?



Please be gentle with my karma!

Re:May not be that important, really....

[fred fleenblat]

You're joking right?

For those few that don't get it, the satellites aren't geostationary, so a failed satellite (once the minimum # is reached) will probably create a dead spot that moves around the planet, in which GPS service is degraded.

Re:May not be that important, really....

[irablum]

that will only happen if there are no backups to shunt into the orbit of the failed satelite. and that will only hapen when if 4 or 5 fail at once. Its not like it costs much more to launch 3 at once over the cost of launching the first one. so, lets say that instead of 2 failing this year, 3 fail. that means that the US government has to launch 3 replacements instead of only 2. big whoop.

Ira

Now, if 10 or 20 fail all at once, well, that's a different story.

Re:May not be that important, really....

[Anonymous Coward]

Now, if 10 or 20 fail all at once, well, that's a different story.

Thats really only a concern if the Aliens use them to run a countdown. Then you'll need them (and a macintosh) to upload a virus to the mothership...

Re:May not be that important, really....

[Anonymous Coward]

Since we have a significant array of military hardware that depends on GPS navigation it is strategically important to maintain coverage over all areas of the planet. Just in case. Even so the Satelites orbit which would leave that "hole" to move around the planet. They definately wouldn't want a blackout over Iraq anytime soon.

Re:May not be that important, really....

[Geoffreyerffoeg]

Please be gentle with my karma!

My dogma ran over your karma.

Wait..uh..I think I got that backwards...but you get the point.

Re:May not be that important, really....

[zippthorne]

It's really really expensive to change the inclination of an orbit. Even more expensive to change its axis. I think it's far more likely that the density of the constellation is such that more satellites than necessary are visible at any time. So if one gets knocked out, you've still got enough, but if several inconveniently close ones get knocked out, some areas would not have enough at certain times of day.

Re:May not be that important, really....

[anthony_dipierro]

Its not like it costs much more to launch 3 at once over the cost of launching the first one.

It's not? Doesn't putting 3 satellites in 3 separate orbits cost roughly 3 times as much as putting 1 satellite in 1 orbit? It's not like they can launch them all on the same rocket, because the satellites have to go into different orbits. In fact, I think you'd have to launch them at different times - just like the shuttle has to be launched at a particular time in order to meet up with the ISS.

OMFG!

[Anonymous Coward]

Do you mean that we'll have to navigate like we did 5 years ago?

That's so 20th century!!!!

The GPS is falling!!!

[Anonymous Coward]

Oh no, Disaster is just around the corner! GPS sure to fail! Passengers sure to die!

Get over it. There are 24 satellites required for total coverage and there are presently 28 satellites, more than enough. The probability of failure is low as demonstrated by the fact that 16 of the satellites have already exceeded their designed life expectancy by 3 or 4 fold.

Do you really think that the US military will allow their ability to put a smart-bomb through an "evil doer's" window to be compromised by a lack of satellites?

<CONSPIRACYMODE>Perhaps the reason that they are allowing GPS to fail is because the US government plans to destroy the world and eliminate the need for GPS all together!!!</CONSPIRACYMODE>

The sky is falling! The sky is falling!

Re:The GPS is falling!!!

[Maow]

Do you really think that the US military will allow their ability to put a smart-bomb through an "evil doer's" window to be compromised by a lack of satellites?

What about their ability to bomb wedding parties with smart bombs?

Or allied soldiers doing exercises in Afghanistan?

It has to be pointed out that ``smart'' bombs are not much more accurate than plain old dumb bombs.

Unless you believe the bumpf, in which case the bombs are smart - more so than the guilible.

No news here

[adsl]

If you put up satellites at a quicker rate then you have too much redunancy in the skies and too much junk in space. It's all a balance, as it should be. Another timely "This is why Europe should run everything" spin story. Be good if Europe invented something really new and useful, for American's to play with (for free)....

Re:No news here

[Darius Jedburgh]

You mean like the BBC World Service?

Re:No news here

[LnxAddct]

Heh, they even want to charge for the things we did give them. The U.N. stated that they would want an international internet tax to pay for the cost of the new organization controlling the internet. That is crazy, and sets a horrible precedent for international taxes.
Regards,
Steve

Re:No news here

[Lehk228]

Be good if Europe invented something really new and useful, for American's to play with (for free)....

Re:No news here

[Xarius]

Yeah, that's what we need! I mean one country (England) in Europe only invented the steam engine, locomotive, 3-piece suit, vaccination, lead crystal, television, radio, the telephone, hovercraft, and both the internal combustion and the jet engine.

We paid for the research, and the development of all of these...

</rant!>

Re:No news here

[dhakbar]

He said new and useful, key word being NEW.

Your examples are all at least 50 years behind us. In addition, none of those inventions were world-wide systems that America made power grabs for... the current situation with the UN/EU wanting power over the internet is completely different than the American use and application of those English inventions. And, for the record, the US developed a jet engine independently and simultaneously.

Re:No news here

[tarp]

The telephone was created by Alexander Graham Bell, a Canadian.

Re:No news here

[IvyKing]

I mean one country (England) in Europe only invented the steam engine, locomotive,

Hmmm, lessee. Seem to recall that the first steam engine was built by a Greek named Hero, although the first useful one was built by Newcomen. The first self propelled vehicle was built by Cugnot of France, another Frenchman built the first steamboat (and that was acknowledged by Fulton). The first high pressure steam engines were built by Trevithick of England and Oliver Evans of the US. Trevithick also built the first steam locomotive. While the first locomotives in the US were imported from England, the US became a net exporter of steam locomotives by the mid-1830's. The first elecric locomotive (albeit model sized) was built by Thomas Davenport of Vermont in 1834.

the telephone

Huh? I would believe "The telegraph" (Wheatstone).

internal combustion

Funny, the names for the two most common ICE cycles are Otto and Diesel - sounds suspiciously German to me.

the jet engine

Which was devloped from turbocharger technology - ISTR was a Swiss development. The Swiss had a working gas turbine in 1940.

One thing you did leave out, the steam turbine was developed by an Englishman by the name of Parsons.

Re:No news here

[nhstar]

...and how much of this was given for free again? I'd love one of those locomotives, though my neighbors may complain...

Re:No news here

[wmorrow]

... Europe invented something really new and useful, for American's to play with'''

You mean like you're playing fast and loose with that apostrophe?

Oops, let me translate in to 'Murrican:

Like your playing fast and lose with that single quote?

Re:No news here

[Anonymous Coward]

Hmm ... the WEB was developed in Europe.

Re:No news here

[KeensMustard]

You mean like democracy?

Re:No news here

[Anonymous Coward]

The world wide web free and new enough for ya?

Re:No news here

[Rhinobird]

The first practical jet engine was invented by an English dude in 1930. And Heri Coanda had something vaguely jet like in 1910, but he's Romanian. Why were the Swiss so far behind?

talk to the wiki

Re:No news here

[Anonymous Coward]

And yet somehow, their universities are better than ours, attracting more of our students than we theirs. And they earn more. Hm!

Re:No news here

[monktus]

Be good if Europe invented something really new and useful, for American's to play with (for free)....

How about something to teach you how to punctuate correctly?

Re:No news here

[martinX]

Seems an Italian migrant living in Cuba invented the telephone. http://en.wikipedia.org/wiki/Alexander_Graham_Bell #The_telephone_and_patent_issues/

Re:No news here

[adsl]

Punctuation scores on only (2) out of my (3) parameters. It's "free" It's "useful" But it isn't "new". So I am afraid that it fails my test;)

Why this scare tactic?

[rolfwind]

The US government/military has a humongous interest in keeping the system up - why be scared about it? It will keep plodding along.

Or am I missing something here?

Ahh, yeah....

[killtherat]

Given the military's dependence on GPS, do you think they would allow one second of interuption? And they use it on almost every corner of the globe. They would notice holes in service much sooner then you ever would.
Call this article what it is, FUD to prop up EU's Galileo.

Re:Ahh, yeah....

[Xarius]

God forbid they'd have to rely on their own wits in the event of failure! Imagine what would have happened to the American revolutionaries in the War of Independence if the GPS had failed!

Oh, wait...

Wrong!

[Anonymous Coward]

The satellites are necessary for calculating the triangular circumference of tao. That's why you need 24 satellites and not twenty seven, or even just ten. Anyway, the point is that if enough of them fail the whole GPS system goes with down. And then you're shit out of luck with confused foreign cab drivers trying to find their way around town. You didn't finish engineering school, did you?

Re:Wrong!

[Sheetrock]

Lao Tzu teaches us that even a journey of 1,000 miles begins with a single step. I believe his wisdom can lead to discovering that where you are is as or more important than where you want to be.

Which, while being an excellent foundation from which to seek enlightenment, can prove a bit of an obstacle when you're simply looking to get from point A to point B... satellites or no satellites.

Re:Wrong!

[Anonymous Coward]

Ahhhh, but every step is simply an illusion of movement. Xena's paradox teaches us that for each step forward one must throw the golden ring with +2 damage. Force meets counterforce, and so one takes a step back. Thus, there is no there there. There is only what is... is!. However, I see that you are most wise. *bow*

GPS Satellite Replacement

[jwink]

It sounds like they are already in the midst of replacing it - check out SpaceFlightNow. The new series is going up with the next generation in the works. Maybe it's just a matter of keeping at or above the crucial 24 limit...?

Don't worry...

[Spy der Mann]

the Chinese will be happy to replace them :)

The real problem with GPS - Linux & Mac Suppor

[standards]

So what we're hearing is that we'll need to lose five GPS satellites - 18% of them - before GPS isn't 100% available world-wide 100% of the time.

Of course, an event could cause us to lose 100% of them at once. But if we just fail one at a time, the redundancy appears to be sufficient. Losing one (or even four) satellites isn't a problem. When one fails, you shoot up another. When a bunch of them fail at once - well, it could happen, but at that point all the redundancy in the world likely isn't going to help.

GPS is a pretty cool technology, but sadly some vendors are crappy when it comes to Linux or even Mac support. Platform support is what we should be pissed about. Damned Garmin just refuses to support anything well except Windows, perhaps because Garmin's desktop software developers aren't permitted to do anything except maintain their ancient Windows software. Some people have managed to get this stuff to work on Linux and the Mac, but it just ain't the same as full, documented support.

Maybe the Mac is too hard for them.

Bush Administration Announces...

[ENOENT]

new "Faith-based" navigation system...

Film at 11.

Re:Bush Administration Announces...

[rubberbando]

Yes! The north star will lead the way!

Re:Bush Administration Announces...

[ENOENT]

Can't use the north star. It's obviously a pagan artifact, with a Latin name and everything.

Re:Bush Administration Announces...

[JahToasted]

And a lot of the other stars have arabic names... hmmm no wonder Bush is putting so much into space initiatives.

blind

[-ryan]

the military lives by GPS these days, no GPS (or poor coverage) would almost halt military operations above the level of a patrol on foot with compass and map. but any infantryman will tell you, there's nothing more dangerous than a cherry ass Lt. with a map.

Re:blind

[Anonymous Coward]

As a cherry ass Lt. who has gotten lost in the woods a few times, I tend to agree.

Re:blind

[Anonymous Coward]

American military is relying way too much on high-tech gear even on basic infantry level. No mobility without GPS? Chees! If someone develops "assasin's maces" (EMP comes to mind) you're screwed bigtime.

As a comparison, Finnish defence forces train every single conscript soldier how to use map and compass as their primary navigational tool. Might be little slower, but atleast they won't need 3 suppy and logistics divisions for every fighting one just to replace dead batteries.

hmmm...

[CDPatten]

well i'm sure all you american haters won't be affected since the US does and never has offered ANYTHING that the proud europe needs or uses.

That aside, I think news like this is just designed to create hysteria. There is no way the us government or the pentagon is going to let anytihng happen to the gps system.

Re:hmmm...

[LnxAddct]

The article is pretty much an advertisement for the European Galileo system.
Regards,
Steve

Hot Spair (they got em)

[Anonymous Coward]

Just so you know...

There are HOT SPAIRS alredy in orbit, not to mention that they can always launch more.

No news here, move along...

Re:Hot Spair (they got em)

[Anonymous Coward]

What's a spair?

They're up longer BECAUSE they didn't fail

[MDMurphy]

It's not that the satellites were just left up there longer because they couldn't be replaced, it's because they've lasted longer than they were intended to. Kind of a "if it's not broke, don't fix it" philosophy.

With redundant satellites and constant monitoring from the ground, it's possible to let one go until it fails, mark it as "bad" and replace it a little later.

The article is wrong about 24 satellites being required for full coverage. A full set is 21 with 3 as spares.

The article also implies that the satellites are failing at greater than planned rate, when the opposite is true.

It's probably just a coincidence that the guy quoted in the article, Norman Bonnor, is a backer of the European counterpart to GPS: Galileo. It's not like he'd have an interest in bashing the GPS system to help further justify Galileo's funding?

Re:They're up longer BECAUSE they didn't fail

[thewiz]

It's not that the satellites were just left up there longer because they couldn't be replaced, it's because they've lasted longer than they were intended to. Kind of a "if it's not broke, don't fix it" philosophy.

Actually, the military's philosophy is to over-engineer items like satellites to make sure they last awhile. If you don't believe me, read a couple of the military specifications (MIL-SPEC) manuals. There is a joke that goes:

Q: What is an elephant?
A: A mouse built to MIL-SPEC.

Am I reading this right?

[GweeDo]

"Sixteen of the present 28 satellites were built to last seven and a half years, but are now between eight and 14 years old"

Um..how could they have been built 7 1/2 years ago and be between 8-14 years old now? I am lost.

Re:Am I reading this right?

[Anonymous Coward]

yr dumb, it never said they were built 7.5 years ago... just the were made to last that long

Re:Am I reading this right?

[Anonymous Coward]

Hint: The word "ago" does not appear in your quote.

Re:Am I reading this right?

[afidel]

It's called reading comprehension.... They were built to last 7.5 years, they have been in service between 8 and 14 years, .5 to 6.5 years longer then their origional design life. Like everything else in space they were overengineered and have surpassed their design life (the minimum time that they should last given expected MTBF of components). This isn't the first time this has happened, and as long as NASA and their contractors (and military contractors) keep up the good engineering principal of overdesigning and underselling it won't be the last.

GPS Constellation status, with launch dates

[Anonymous Coward]

From: ftp://tycho.usno.navy.mil/pub/gps/gpstd.txt

A. BLOCK II/IIA/IIR/IIR-M INDIVIDUAL SATELLITE STATUS

SVN PRN
15 15 Launched 01 OCT 1990; usable 15 OCT 1990; operating on Cs std
24 24 Launched 04 JUL 1991; usable 30 AUG 1991; operating on Cs std
25 25 Launched 23 FEB 1992; usable 24 MAR 1992; operating on Cs std
                    Scheduled unusable 20 Oct 0130 to 1330 UT for repositioning
                      maintenance (NANU 2005131/14 OCT)
26 26 Launched 07 JUL 1992; usable 23 JUL 1992; operating on Rb std
27 27 Launched 09 SEP 1992; usable 30 SEP 1992; operating on Rb std
29 29 Launched 18 DEC 1992; usable 05 JAN 1993; operating on Rb std
30 30 Launched 12 SEP 1996; usable 01 OCT 1996; operating on Rb std
31 31 Launched 30 MAR 1993; usable 13 APR 1993; operating on Rb std
                    Unusable 14 Apr 1634 UT and will remain unusable until
                      further notice (NANU 2005055)
32 01 Launched 22 NOV 1992; usable 11 DEC 1992; operating on Cs std
33 03 Launched 28 MAR 1996; usable 09 APR 1996; operating on Cs std
34 04 Launched 26 OCT 1993; usable 22 NOV 1993; operating on Rb std
35 05 Launched 30 AUG 1993; usable 28 SEP 1993; operating on Cs std
36 06 Launched 10 MAR 1994; usable 28 MAR 1994; operating on Rb std
37 07 Launched 13 MAY 1993; usable 12 JUN 1993; operating on Rb std
38 08 Launched 06 NOV 1997; usable 18 DEC 1997; operating on Cs std
39 09 Launched 26 JUN 1993; usable 20 JUL 1993; operating on Cs std
40 10 Launched 16 JUL 1996; usable 15 AUG 1996; operating on Cs std
41 14 Launched 10 NOV 2000; usable 10 DEC 2000; operating on Rb std
43 13 Launched 23 JUL 1997; usable 31 JAN 1998; operating on Rb std
44 28 Launched 16 JUL 2000; usable 17 AUG 2000; operating on Rb std
45 21 Launched 31 MAR 2003; usable 12 APR 2003; operating on Rb std
                    Unusable 13 Oct 0217 to 0905 UT due to repositioning
                      maintenance (NANUs 2005129, 2005130/13 OCT)
46 11 Launched 07 OCT 1999; usable 03 JAN 2000; operating on Rb std
47 22 Launched 21 DEC 2003; usable 12 JAN 2004; operating on Rb std
51 20 Launched 11 MAY 2000; usable 01 JUN 2000; operating on Rb std
53 17 Launched 26 SEP 2005
                    For more information about PRN17/SVN53, see:
                      http://www.spaceflightnow.com/delta/d313a/
54 18 Launched 30 JAN 2001; usable 15 FEB 2001; operating on Rb std
56 16 Launched 29 JAN 2003; usable 18 FEB 2003; operating on Rb std
59 19 Launched 20 MAR 2004; usable 05 APR 2004; operating on Rb std
60 23 Launched 23 JUN 2004; usable 09 JUL 2004; operating on Rb std
61 02 Launched 06 NOV 2004; usable 22 NOV 2004; operating on Rb std

Re:GPS Constellation status, with launch dates

[meatplow]

Why isn't this modded up. Highly Informative.

Rolling Eyes

[MikeyTheK]

I got a chance to visit one of the facilities that manage GPS for the military, and talk to staff at length. So, while I'm not an expert on this topic, here's some of what I (think) I learned Twenty-four satellites are required for full coverage. That's assuming that you want full-featured coverage across the entire globe, with excellent accuracy, i.e. with 5 or six satellites visible to your receiver in your horizion. There are places in the world where there aren't as many (four is the minimum, if I remember, to get your exact position including altitude.
Lifespan of the satellites includes not only electronic function, but fuel supply for retasking.
The bases that manage the constellation (I am aware of two, but one would think there would be more)can compenstate for various issues with the satellites' clocks, some of which are issues related to age. In addition, since the master clocks are here on Earth, various satellites can be controlled more-or-less directly in the event that their clocks fail. In full manual mode, it it thus possible to lead a rogue object or person astray, but within the margin of error so that the person or object would have no idea that it/they were being "misguided".
I think Chicken Little ought to worry a bit less about the status of the constellation. The staff managing the constellation is well-aware of what's going on, has its own separate Command, and launch facilities that are quite capable of putting additional assets in orbit in short order.

No matter...

[korbin_dallas]

Remember kids,

No matter where you go, there you are.

Can I get a job

[squoozer]

I would love to have a well paid job coming up with solutions to "difficult" problems like this. I'd give my employer the first solution for free:

Launch new satelites that are compatible with the old system!

then I would charge a fortune for all the other ideas once I had got them hooked. My god I can't believe anyone is even questioning this. It's a total no brainer. Have IQs dropped recently or is it just that all the money has been spent on other things?

Working at the GPS hub

[iamweezman]

As an active duty Air Force tech controller I work almost daily with the satellite operators that "fly" the GPS satellites. Some of their systems are more than antiquated, but still function with adequate redundancy built in. Although the lifespan might have been eclipsed the telemetry data recieved by the operators give them the state of health of the satellites which allows them to plan for future launches.

In fact, a newer GPS satellite was just launched weeks ago. As stated before, the DOD has a special spot in their hearts for GPS. The GPS operators get treated extra special because of the US military's reliance on them. There are already plans in place for each satellite to be super-orbited when the time comes and for a new launch to follow.

In other words, if the military isn't worried about it, neither should we be.

Re:Working at the GPS hub

[Phronesis]

In other words, if the military isn't worried about it, neither should we be.

I just love it when someone says, "I'm from the government. Trust me."

Capturing Osama bin Laden and building a functioning democracy in Iraq are even greater priorities for the military than maintaining GPS operations. According to the Commander in Chief, things are going swimmingly on both of those fronts so if I follow this logic, if the military is not worried about Iraq or Osama, neither should we be.

Re:Working at the GPS hub

[plover]

Nice strawman, but your argument doesn't hold water.

First, when did you discover their priority list? And second, just because George Bush is one of the biggest liars ever to disgrace the White House, and Donald Rumsfeld is by far the biggest liar ever to hold the Secretary of Defence chair DOES NOT mean the lies extend to our military. (It's really sad, when you think of it, that we can trust our Army to tell us the truth far more than we can trust our elected officials.)

Anyway, it's very simple. It's a helluva lot easier to deal with math and physics than with terrorists and fundamentalists. Computers and rockets make a lot more sense than people since they have no incentive to lie, which makes the experiments a lot more repeatable. Launching a half dozen satellites a year is a cakewalk compared to hunting a psychotic murderer hidden in someone else's mountain range. And Delta rockets aren't planting IEDs or driving car bombs into recruitment centers -- stupid, gullible fanatics are.

Iamweezman was absolutely right in analyzing this economically: the military has too much invested in GPS to allow it to fail. They'll find maintenance money for it even if they have to cut other essential services. Without GPS, JDAMs and JSTARs won't find their targets, tanks will have to fall back to manual control, and even artillery firing systems will probably be messed up. Not that they couldn't wage a war, but they'd be far less effective without GPS.

Don't worry about GPS. They'll find money to spend to keep it in orbit. "Trust me."

Re:Working at the GPS hub

[Phronesis]

I was too snide in my comments, and for that I owe the poster an apology.

But my major point stands. The source is someone posting to slashdot, claiming privileged information that is not subject to independent verification, telling us to trust him because he's part of a government agency (specifically the military).

Just because someone is a government functionary does not mean that I trust him when he makes claims based on evidence that's not available for scrutiny. I'm not saying that I lose sleep worrying about GPS, but that I don't find the argument, "If the military isn't worried, neither should you be" even remotely persuasive.

Total BS

[huxrules]

Imagine someone from th UK saying that the US GPS is going to die. Why would he do that? Possibly to show how important it is for Europe to have its own systems? Thats right kids- the EU wants their own GPS system. Anyways the GPS system will work fine, I'm sure if there is less then 24 sats we will simply move orbits on some sats so that the US will retain total coverage. And we are launching new sats all the time. On top of that and there is already the Russian backup- GLONASS. Which many new handheld receivers pick up. So dont fret.

Oblig. Futurama

[Xarius]

Fine screw you, we'll build our own GPS/DNS system! with blackjack! and hookers!

in fact, forget the system!

ya go to space with the satellites you have

[gelfling]

not with the satellites you wish you had.

Preventive vs Curative ?

[Touisteur]

What about cheap preventive maintenance with uninterrupted service, instead of the so usual curative maintenance with cut for 2 months in some areas and a launch in minimum delay (so, maximum cost).

Japanese industrials understood that 20 years ago. Are US so cheap we can't replace some small low-power signal emiting with embedded atomic clock before they die ? =o/

Hopefully Galileo will be compatible with GPS and nobody'll get interrupted but US Missiles. =o)

Re:Preventive vs Curative ?

[Rakishi]

huh? If a sat dies then there are 4 working spares already in orbit which can replace it. As I said above, you'd need to have multiple sats (5, potentially less if spares can only take over certain orbits each) die in the time it takes to get replacements up for there to be any real downtime.

Redundancy is already in place, right now its all a question of "how few sats can we launch while keeping the chance of failure very low." If we launch too early then we have an extra satellite in orbit which provides unnecessary redundancy and doesn't do anything while at the same time already being subjected to aging. In other words, over time such behavior would lead to more frequent need to replace the satellites. Launching sats isn't exactly cheap.

drumming up funds for new style GPS satellites

[Anonymous Coward]

I was wondering how long it would take before we'd hear these stories. The military just sucessfully launched the first of the new autonomous (self-navigating) GPS satellites. The problem is, it is only autonmous if it can talk to a large number of similar new-style satellites. Since there is only one of thse in orbit, things must be pretty lonely. Some hot-shot in Space Command must just be itching to try out his new toy and is bummed that he'll have to wait another 15 years till the constellation is replaced with these. What is funny, in 15 years there will be a newer and better GPS satellite. If they sit back and be mellow there will always be a few of the latest and greatest in orbit. If they accellerate the schedule too much they'll be sticking future Space Command jocks with their old and decepit junk. The key truly seems to be to meter out the launch rate such that we launch 2 per year and have a constellation of ~30 satellites between 0 and 15 years old in orbit.

well aint that great,

[Anonymous Coward]

just when I got mine to run on my ubuntu notebook!

I am not a script, i am borg.

If GPS fails, no problem

[Anonymous Coward]

Just go to maps.google.com, type "here" in the search box and press Enter.

Falling Satellites

[Anonymous Coward]

They'd better not hit the Spice Channel satellite on the way down! >:(

Already taken care of

[iabervon]

Since that article was written, they launched a new satellite, as the article mentions at the end. This is the first of the new series, currently in testing and scheduled to be launched as older satellites fail. When the article was written, it was a vaguely reasonable concern that they didn't yet have new satellites ready to send. Also, it's traditional to post stories on a topic in chronological order, so that they make sense.

Are you sure

[baldbobbo]

I think this is in response to commercial GPS systems. According to Air Force Magazine (see pg 23 (PDF)), we have 28 servicable. I recall that they launched a few GPS birds about a year ago from Nellis AFB as well. Again, I think this article pertains to civilian GPS services, which practically speaking, isn't nearly as important as maintaining military coverage (especially if the Chinese are trying to reinvent the system and Europe wants to play ball with them).

Re:The real problem with GPS - Linux & Mac Sup

[Anonymous Coward]

I use my Garmin Forerunner 201 under linux using a program someone cobbled together and a series of perl scripts. Works great.

what is failure?

[morcheeba]

I know that I'm not the oldest person here, but I've been using GPS since before all the satellites were up (~1992?).

The main problem is that you need a larger view of the sky to see the minimum number of satellites (3-4) -- indoor reception was difficult because you were limited to seeing 1/2 of the sky.

With fewer satellites, their geometry in the sky can become a problem -- if they are too close together, you'll get more measurement error (or, technically, GDOP).

Back then, if you really needed a gps fix, there were orbit prediction programs... you could input your general location, and it would tell you what the availability would be at different times in the day.

Anyone can do a test with their own GPS. I often see 6,8, or 10 satellites. If half of those satellites failed, I would still be able to get readings in open sky (with less precision, of course, because of GDOP).

Such BS

[chadseld]

There is nothing to worry about, this article is inflammatory. Do you have any idea how many weapon systems rely GPS? I work in the defense industry, GPS is everywhere. When the current satellites start falling down, we will send up more. In fact, those plans to 'weaponize' space are mostly a reaction to the realization of how important the GPS system is. It is a single point of failure and must be protected. Do you really think the armed forces are going to let the system fail due to neglect?

Re:Such BS

[Anonymous Coward]

In fact, those plans to 'weaponize' space are mostly a reaction to the realization of how important the GPS system is.

Interesting point. I wonder how hard it would be for "the terrorists" to launch a rocket up to interfere with the GPS system. The exact orbits of the satellites are published, since they have to be in order for GPS to work. Plus any location in the world can see 4 satellites at any time, so "the terrorists" could work from anywhere.

All it would take is a little rocket science.

Absolutely

[Sycraft-fu]

People seem to forget that GPS is a military system, developed for military purposes. They opened it up for civilian use and that's wonderful, it's been a massive boon, but it was developed for the US Military alone. It is also the prime location system for just about all military units, from individual soliders up to large ships these days. While I'm sure the military COULD function without it, it would seriously screw things up.

It's a strategic asset, and they aren't going to let it fail. If it was all private run, ok maybe then there'd be a worry that someone would decide to cut costs on it and let it slide, but it's the military's toy and there's no way in hell they are letting it fail.

All the military implications aside, US commercial intrests rely very heavily on GPS these days and letting it fail would also not be in the economic intrest of the US government.

Re:Absolutely

[fluffy99]

Exactly. It also means the Military can scramble or shutdown the civilian use at any moment. For the longest time, they added SA which limited the accuracy of civilian positioning equipment. You don't honestly think a non-US military would rely on it do you? Other than the Brits who have their nose up the US's arse.

Re:Absolutely

[Anonymous Coward]

>but it was developed for the US Military alone.

Which is why other countries around the world are building thier own GPS systems. You can always use the EUs when yours fails. :p

Re:Absolutely

[Anonymous Coward]

You don't honestly think a non-US military would rely on it do you? Other than the Brits who have their nose up the US's arse.

You forget that the US has it's nose up Israel's backside. Or is that Sharon has his hand up Bush's...

Does Location of Spares Matter?

[richyoung]

Is it really possible to scoot a spare over to the geosynchronous orbit of the one that needs replacing? I mean, if there are 24, they'd be placed every 15 degrees around the globe - but optimal placement of the three spares would be every 120 degrees (90 for four spares). A failure could occur up to 60 degrees away from an available spare (45 for four spares). How easy is it to move a satellite out of geosynch and then back in, 60 degrees from its original position? Especially when you consider the available fuel?

I guess you could brake/accelerate to a slightly faster/slower orbit and allow the spare to slowly catch/be caught over many, many orbits until it was positioned, then return to geosynch. But the military would probably need any gap fixed ASAP, requiring a less efficient pair of burns, requiring more fuel and shorter satellite lifespans.

Re:Does Location of Spares Matter?

[3rdParty]

GPS isn't geosynchronous, so any failure would only mean a temporary potential for degradation of accuracy. I would presume that the spares are orbiting in a space not far from the next likley failure, rather than just randomly placed.

Re:Does Location of Spares Matter?

[NiallOBroin]

GPS satellites are not in geosynchronous orbit but rather in intermediate circular orbits (they're in six orbital planes). But it is an interesting question as to how spares are handled. I guess they must have enough fuel so that they can be positioned to replace a dead satellite.

cell service implications

[_pi-away]

GSM and CDMA (and CDMA2000) all rely on precise synchronization between towers, this is done using GPS. Without it, you're going to start having cell problems real quick.

UMTS (WCDMA) networks would not be affected however, they specifically designed UMTS to not need that synchronization because they didn't want to have their communication infrastructure dependent on a US controlled system like GPS.

Why should Europe care?

[Anonymous Coward]

We're building our own - so what do we care about American crap failing?

Sometimes I think we Europeans unjustly consider the US our friend, strange how quickly things change - one moment I love everything the US represents, now I just laugh when you hurt. Thanks go out to all the great Americans out there, thanks for changing my point of view.

Re:Why should Europe care?

[Anonymous Coward]

"We're building our own - so what do we care about American crap failing?"

RTFA. You're 4+ years off from launching your own.

In it's design, you decided to purposefully design it over our frequency; so much for your ingenuity. Don't complain when we stuff something down your GSM frencies in the near future.

"Sometimes I think we Europeans unjustly consider the US our friend, strange how quickly things change - one moment I love everything the US represents, now I just laugh when you hurt. Thanks go out to all the great Americans out there, thanks for changing my point of view."

That says it all--you laugh when natural disasters hit, when inconvenience occurs, when our people die. You take pride in who you are based on other people's suffering. That's the new European standard, eh? What mighty countries you have become. What a great standard you have to valuate yourselves.

Don't worry. We really don't like you all anymore, and realize more of what this EU business is, which is not an economic powerhouse but an assembly of bashers and moaners who are copying the US to give folks "options". It'll just end up being another Concorde.

At least we're being more consistent about it. You aren't reliable, you've implemented trade sanctions against us under the guise of consumer protection, you back nations with really, really shitty governments yet criticize every mistake of ours, minor or not, what was one of your strongest allies has already established new trading partners, you're "what have you done for me lately", we send millions over to fight for you over your lands and you can barely spare a few thousand, you excuse peace at the expense of human rights abuses, and you talk without doing anything of substance.

You know who I feel sorry for? All the veterans who fought for Europe. Only to have those countries establish themselves with the principle focus of their economic plan being to compete against the US. I have better feelings for the Soviets than I do for the EU because even in their corrupt system, they're consistent and they don't shit where they eat.

As other have said, should have just let the Germans or the Soviets have their way with you and been done with it. I'd rather my country, the US, pave the path to hell with good intentions than be the jackasses sitting on the fence doing nothing while a girl is being gang raped that the Old World has come to represent. Then again, Europeans have already forgetten what happened when Iraq pulled out of Kuwait, or when the Soviets entered Berlin, don't you?

Hope you like our web?

[Anonymous Coward]

Considering we invented the WWW and the browser I hope you enjoy playing with it for free. The WWW was created by an Englishman working for the European research lab CERN.

LORAN

[ChrisMaple]

Isn't 1/4 mile accuracy good enough for anybody?

in other news...

[Yonder Way]

...the EU demands that the US cede control of the Global Positioning System.

Lot of old stuff you've listed there

[Anonymous Coward]

The newest one you've listed is 65 years old. Most of it is starting to push into hundreds of years old, if not older. Got anything new?

Re:Oh FUCK

[Anonymous Coward]

AHHHH! FUCK! Where the FUCK am I? Arghhh, FUCK! Where AM I! FUUUUUUUCK! AHHH! WHERE THE FUCK AM I? If only I had some fuckin GPS to tell me WHERE THE FUCK I AM!!!!

From TFA

[Anonymous Coward]

CATS: You are on the way to destruction.
Captain: What you say !!
CATS: You have no chance to survive make your time.
CATS: Ha Ha Ha Ha ....

jets didn't come from turbochargers

[YesIAmAScript]

Leaving off the Swiss turbocharger thing (Americans made them practical).

Jets just flat out don't come from turbochargers.

Jets use fan blades, turbochargers do not. Turbochargers use impellers and are only compressors. Jets have different compression sections, burners (flame fronts) and actually make thrust.

It's like saying cars came from trains because both have round wheels. It just doesn't work.

I don't see how England invented TV. Nipkow (German) invented mechanical TV, and Farnsworth (American) invented electronic TV (far more important to getting us to where we are now).

The grandparent did miss that England invented RADAR. A great invention.

Note to other posters, Alexander Graham Bell was not Canadian. He resided there fora while, but never changed nationality, he was a Scot up intil he became American. He was a Scot (living in Boston?) when he invented the telephone.

Re:jets didn't come from turbochargers

[IvyKing]

Jets use fan blades, turbochargers do not. Turbochargers use impellers and are only compressors. Jets have different compression sections, burners (flame fronts) and actually make thrust.

First off, turbochargers make use of a turbine to drive the compressor.
Secondly, many of the early jets used centrifugal compressors (impeller).
Thirdly, several people have made small turbojets by grafting a combustion chamber between the compressor and turbine of an off the shelf turbocharger.

One of the reasons that GE got its start in jet engines (when the RAF was looking for an American company to work on jet engines) was because of their experience with turbochargers. GE also had a lot of experience with other turbomachinery which didn't hurt.

The grandparent did miss that England invented RADAR.

Yes and no. The US Naval Research Labs did some early work in the 1920's and Deak Parsons was working on the proximity fuze in the late 30's - which first saw use at Guadalcanal in early 1943. In addition, the US had many RADAR sets of domestic design operating in the VHF spectrum - including one operating on the north end of Oahu on the morning of Dec 7, 1941.

Re:jets didn't come from turbochargers

[Lord Haha]

(Alexander Bell) was Living in Cape Breton :)

Re:jets didn't come from turbochargers

[surprise_audit]

While not actually English, a Scot named John Logie Baird is said to be the first person to demonstrate a working television.

"Although the development of television was the result of work by many inventors (including Baird, Paul Gottlieb Nipkow and Boris Rosing; see Television: History), Baird is one of its foremost pioneers. He is generally credited with being the first person to produce a discernible image on a television screen, and would go on to produce many other advances in the field."

The BBC used the Baird system for some years before switching to a wholly electronic system.

Re:jets didn't come from turbochargers

[Anonymous Coward]

Actually a german invented the RADAR somewhere in the twenties which the brits later produced usable versions of.

bet a nickle

[Anonymous Coward]

bet a nickle they already have replacement sats in orbit for those if "something happens" to the currently used ones. I mean, this is the DOD you are talking about, they got the cash, they got the incentive, they got the "need to know" to keep it quiet. All their critical warfighting absolutely with no shadow of a doubt depends on GPS, so ya think they don't got backup in place for contingencies?

National Defense

[bhav2007]

These fears may be well founded, but in the end I don't think they will play out. It really all comes down to the fact that GPS is so tied into military systems. If its a matter of national defense, it will get done. They didn't program all of the navigation systems in the latest attack helicopter to use GPS just to have the system break down a few years from now. And, of course, if you can pull it out of the military budget, then you can practically plate the things in gold ;)

That reminds me...

[Anonymous Coward]

Must do something about all those old Windows NT 4 servers at work...

Move Along, Nothing to See Here

[Captain Chad]

The GPS system has built-in overkill. At any given time there are about a dozen satellites within view, and a receiver only requires four to work correctly (okay, theoretically only three if you have a clock). So even if we were to lose some of the satellites, GPS receivers would still work.

There could be some degradation—using more than four satellites will give better accuracy. And a satellite on the horizon will give a weaker signal than one straight above, thus adding noise to the process and possibly degrading accuracy. But in general, the GPS system will still work and will give reasonable results.

Does this mean ...

[LaughingCoder]

cruise missiles are going to have to pull over and ask for directions?

Re:GLONASS may be total BS

[Anonymous Coward]

I wouldn't count on GLONASS:

                                    GLONASS Constellation Status
                                            ( October 14, 2005)

GLONASS Cosmos Plane/ Frequ. Launch Intro Status Outage
number number slot chann. date date date
796 2413 1/01 02 26.12.2004 06.02.2005 operating
794 2402 1/02 01 10.12.2003 02.02.2004 operating
789 2381 1/03 12 01.12.2001 04.01.2002 operating
795 2403 1/04 06 10.12.2003 30.01.2004 operating
711 2382 1/05 02 01.12.2001 15.04.2003 operating
701 2404 1/06 01 10.12.2003 09.12.2004 operating
712 2411 1/07 04 26.12.2004 06.10.2005 operating
797 2412 1/08 06 26.12.2004 06.02.2005 operating
787 2375 3/17 05 13.10.2000 04.11.2000 operating
783 2374 3/18 10 13.10.2000 05.01.2001 unusable 03.10.2005
792 2395 3/21 05 25.12.2002 31.01.2003 operating
791 2394 3/22 10 25.12.2002 10.02.2003 unusable 11.10.2005
793 2396 3/23 11 25.12.2002 31.01.2003 unusable 09.10.2005
788 2376 3/24 03 13.10.2000 21.11.2000 unusable 03.10.2005

Note: All the dates (DD.MM.YY) are given at Moscow Time (UTC+0300)

Note that the formatting is a little off, but you can get the idea. After launching around 100 GLONASS SVs, there are 10 operational today, with a max of 14 if they all stay lit at once for a while.

Additionally, the history of the project is interesting:

http://www.glonass-center.ru/hist_e.html

I wonder how much the EU has learned from the US and the USSR/Russia so they can create such a perfect system as Galileo?