Geostationary GPS Satellite Galaxy 15 Out of Control 379
Bruce Perens writes "The Galaxy 15 commercial satellite has not responded to commands since solar flares fried its CPU in April, and it won't turn off. Intelsat controllers moved all commercial payloads to other birds except for WAAS, a system that adds accuracy to GPS for landing aircraft and finding wayward geocaches. Since the satellite runs in 'bent pipe' mode, amplifying wide bands of RF that are beamed up to it, it is likely to interfere with other satellites as it crosses their orbital slots on its way to an earth-sun Lagrange point, the natural final destination of a geostationary satellite without maneuvering power." (More below.)
Bruce continues: "The only payload that is still deliberately active on the satellite is its WAAS repeater. An attempt to overload the satellite and shut it down on May 3 caused a Notice to Airmen regarding the unavailability of WAAS for an hour. Unsaid is what will happen to WAAS, and for how long, when the satellite eventually loses its sun-pointing capability, expected later this year, and stops repeating the GPS correction signal. Other satellites can be moved into Galaxy 15's orbital slot, but it is yet unannounced whether the candidates bear the WAAS payload."
Bastard (Score:5, Funny)
Double Bastard (Score:4, Insightful)
And create all that space debris that will jeopardize countless other satellites?
The only way (Score:5, Funny)
Re:Double Bastard (Score:5, Funny)
Duhh, nuke the debris with a second one. ;-)
Re:Bastard (Score:5, Funny)
That shouldn't be very hard. You do know what the unofficial government payload is on those satellites, right? Titanium cased nukes. The launch is easy. Just aim and give it a little shove. Then it detonates at the appropriate altitude. It's so much more efficient to already have your nukes up there, than to have to launch them from the surface and wait for them to come back down.
You really don't want to just pop one in orbit though. It'll leave one heck of a mess up there. It's not just debris, it's radioactive debris.
Re:Bastard (Score:5, Informative)
You really don't want to just pop one in orbit though. It'll leave one heck of a mess up there. It's not just debris, it's radioactive debris.
Not only that, but the blast itself will fry more satellites, which will have to be nuked in turn.
http://en.wikipedia.org/wiki/Operation_starfish_prime [wikipedia.org]
Target practice? (Score:5, Funny)
Haven't the military got some super satellite-busting weapon they've been dying to test?
Re:Target practice? (Score:4, Insightful)
I am thinking that the X-37b with the ABL (big laser) would work wonders for just this sort of thing.
though one would want to take really really careful aim. If you hit a large spinning mirror you could fry someone else.
Re:Target practice? (Score:5, Insightful)
... because a big debris cloud in orbit is a whole lot safer than one satellite in a known orbit.
Re: (Score:2)
Well, in this case, maybe it is. With a projected path that sends it in the way of a major TV carrying satellite, and furthermore the transmission payload still blasting out signal at the same frequencies, this could knock many networks off many cable systems at the same time. That's pretty high on the "avoid this" list.
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... and nothing of value would be lost.
(Besides, losing a few cable channels for a little while isn't much compared to actually losing satellites from debris hits. People can do without Fox News for a few days.)
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People can do without Fox News for a few days.
People will have to get their unfounded BS the old fashioned way.
Re:Target practice? (Score:5, Funny)
(I kid, I kid)
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The problem is Futurama is returning in a month and a half. We cannot possibly advocate losing broadcast satellites!
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That would be pretty bad, but its still better than scattering a debris field across an entire set of orbital trajectories. At least with this, they can maneuver satellites out of the way until a deorbit strategy can be made. If you blow it up in place, you'll have to wait until the pieces fall out due to the minuscule drag that exists in high orbit.
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Except that the debris could just as easily take those same networks off the system even longer if they strike the relevant satellite.
Re:Target practice? (Score:5, Insightful)
Comment removed (Score:4, Insightful)
Re: (Score:3, Funny)
We could always send up a mission to retrieve the dead satellites with the space shutt- Never mind.
Re:Target practice? (Score:4, Informative)
Not to mention the fact that the Shuttle doesn't have the thrust necessary to put it into Geosync... heck, it can't even make it to GTO. VERY out of reach.
Comment removed (Score:4, Interesting)
Re:Target practice? (Score:4, Interesting)
Interesting idea... I do see several possible problems with it though...
Re:Target practice? (Score:4, Interesting)
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How does a laser that would heat up the transmitters so that they would stop transmitting causing interference which is what they are worried about create more debris?
think before you type. The ABL doesn't make missiles go boom either. It heats up and the shorts out the guidance systems, making the missiles fall off target and hopefully out of the sky.
Re:Target practice? (Score:4, Informative)
Think before you type.
The YAL-1 doesn't "heat up and short out guidance systems", it and the NC-135 used a laser to burn through the missile's wall and causes a structural failure.
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Why can't anti-satellite systems hit the target from ABOVE, and direct debrit towards re-entry?
Madcow
Re:Target practice? (Score:5, Informative)
You want to hit the satellite away from the direction it's orbiting in, so that it loses enough orbital velocity to descend into the top-most part of the atmosphere where drag will slow it down even further and pull it down.
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"Morbo is not spelled that way!" - Morbo
Light pressure (Score:5, Interesting)
Re:Light pressure (Score:5, Informative)
Really... massless particles can create pressure now?
Yes. Photons carry momentum despite having zero rest mass.
Re: (Score:3, Informative)
Yes, they can: http://en.wikipedia.org/wiki/Solar_Sail [wikipedia.org]
Massless doesn't mean they don't have momentum.
Re:Light pressure (Score:5, Funny)
Re: (Score:3, Insightful)
I guess you never saw one of these in science class back in high school:
http://www.ecrater.com/product.php?pid=7519326 [ecrater.com]
Re:Light pressure (Score:5, Informative)
Light actually does have a pressure. It is incredibly small, but in enormous quantities (like the sun or lasers) it can be quite powerful. I believe something like Intensity / c is radiation pressure formula. Not sure though. But it definitely has pressure, without radiation pressure our creation of Bose Einstein condensates would totally fail. Photons may not have rest mass, but they have some momentum because matter is just a form of energy. E.^2=M.^2.*c.^4 Its not much, but enough of it has measurable effects. A good part of the time the pressure is converted to heat (like on earth, or in our metal cutting lasers).
Uh, YES. Reality is a fantastic thing, i would suggest learning more about it, it is an enriching experience. Or you could just go on being a dumb-ass making the world a harder place to live in because people that know things have to sit around and explain things to you like a five year old, or just accept you people attempting to influence the world around you without understanding the possible consequences of your actions.
Re: (Score:3, Funny)
Or we could just send a couple of GLG20's into the mountainous regions at the border of Afghanistan and the Soviet Union to smash a SatScram terminal with a rock, save the day, and have sex with a super cute Russian soldier, while she strangely looks like a supermodel, and another hot GLG20
Re:Target practice? (Score:5, Insightful)
Too high.
The recent anti-sat missiles which China [wikipedia.org] and the USA [wikipedia.org] tested just took out satellites which were in low earth orbit, 400km max. This satellite is in a geosynchronous orbit, which is about 36,000 km high (and for reference, the moon is 380,000 km away, so a moon-earth Lagrange point would make a little more sense).
And these anti-sat missiles don't even have to reach a 400 km orbit, an epileptic orbit which would intersect with earth again (but happens to intersect with another satellite first) is sufficient, that is why they could be launched from a warship. Not that taking down a geostationary sat would be impossible - since they don't zip overhead with 25,000 km/h it could actually be easier, but these weapons are not build for it and would need another booster base.
Re:Target practice? (Score:5, Funny)
"epileptic orbit"
I'd love to see an orbit do that!
Re:Target practice? (Score:5, Funny)
I don't know, personally I shudder to see something like that.
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At least he didn't say it was exponential. It literally makes my blood boil when people misuse that word.
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Everyone (apart from the Chinese [abcnews.com]) is very hesitant to gratuitously blow stuff up in orbit, because the debris stays in orbit and makes space missions more dangerous and difficult.
Where'd my cable channels go? (Score:5, Informative)
Here's a list of what AMC-11 is used for [lyngsat.com] on Lyngsat.
Basically, if this wayward sat gets in the way, the average cable/DBS subscriber in the USA is going to wonder where half their digital channels went.
Re:Where'd my cable channels go? (Score:5, Insightful)
Re:Where'd my cable channels go? (Score:5, Funny)
Are you kidding? Imagine this happening during the last episode of Lost.. It would make the Rodney King riots look like a day at the beach...
Re:Where'd my cable channels go? (Score:5, Funny)
Unless this is PART of the last episode of Lost...MAN they're good!
Not necessarily... (Score:5, Interesting)
In 1998, Galaxy IV blew out [wikipedia.org], which controlled commercial communications for a metric assload of services (including my former employer's dealership communications network, FordStar [fordstarconnect.com]). I (and every other remote admin) got a $50 bounty per dish that we hurriedly re-pointed to a different satellite. Cleaned the whole thing up across the global network (four continents) in less than three weeks.
I'm fairly sure that cable TV, which has more sats on tap and relatively less dishes to re-position (and nobody has to crawl on top of a zillion roofs with a wrench and a compass in hand), could likely recover in very short order - probably hours.
That said, there's always the danger of a chain reaction (after all, there's a LOT of satellites in geosync orbit) - if not at this time, then certainly in the coming future, as the numbers continue to increase.
Re:Not necessarily... (Score:5, Interesting)
Thing is... that 1998 event left several lesser-known cable channels holding the back as bigger-money former Galaxy IV customers used their pre-empt rights on the other birds to keep themselves on the air. A natural supply/demand price increase situation arose from this.
The SkyTel service never recovered. Customers of that service were migrated to cellular-based pagers.
Re:Not necessarily... (Score:5, Funny)
cellular-based pagers
PAGERS???? What the hell is a pager?
Re:Not necessarily... (Score:4, Funny)
PAGERS???? What the hell is a pager?
Ask your grand parents.
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a short, relatively unintelligible message that gets interpreted through wishful thinking to something of meaning.
my god, twitter reinvented ouija.
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cellular-based pagers
PAGERS???? What the hell is a pager?
Twitter, but in one direction only.
Re:Not necessarily... (Score:5, Funny)
It's a thing people used to wear on their belts after onions went out of fashion.
Re:Where'd my cable channels go? (Score:4, Informative)
According to Wikipedia, all television signals have been transferred to other satellites [wikipedia.org]. So unless your cable company hasn't received the memo, there should be no interruption of service.
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Actually, they moved G-12, an older sat available as a spare, into 131 degrees W to take the place of G-11. The only action required by cable companies was to make sure their dishes were peaked so that while the transition was happening there was enough wiggle room to see both birds at the same time.
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You're confusing the issue. The wayward satellite is useless, and all of it's content has been moved elsewhere. The problem is the late-May to early-June threat to AMC-11's signals... which is still functional and "evasive maneuvers" for it are planned to keep it's signals going, but the jury's out as to whether this is going to work.
Re:Where'd my cable channels go? (Score:5, Funny)
no thats just comcast service as usual.
Re: (Score:3, Insightful)
Last I checked, the FCC only mandated the switch to digital over the air and had nothing to say what format was broadcast over private networks. That decision is just based on greed. (more free bandwidth and more converter box rental fees.)
Re: (Score:3, Interesting)
Last I checked, the FCC only mandated the switch to digital over the air and had nothing to say what format was broadcast over private networks. That decision is just based on greed. (more free bandwidth and more converter box rental fees.)
Allow me to expand on that. It's sad that just digital SD and not full HDTV is the only "mandated" standard when both could have been forced given a couple more years to allow for larger HDTV penetration. Forced unavailability of old 4:3 on the PC and LCD industry was more effective to force us all to a 16:9. These wider but shorter screens are little more than paperweights when you consider that larger compression-based distortion and forced resolution stretches are more obvious on them than our old TV's..
Cable should of used clear QAM for exp basic / non (Score:3, Insightful)
Cable should of used clear QAM for exp basic / non hbo , max , show, ppv and out of market sports. But what we got was paying $6- to up $20 per tv to rent a cable box. A cable card system that the cable co's make in to a joke and very few cable card boxes can do SDV (needs a cable co add on tuner). Tru2way is all most nowhere. The dta's are a joke analog sd only out and you get less then the old analgo line in some areas and you missing out on stuff like YOUR RSN over flow channel forcing you in Chicago Lan
Not Sun-Earth Lagrange points (Score:5, Informative)
It should be mentioned that the stable libration points for geostationary satellites are earth-relative (105 deg west, 75 deg east) and are not the same as the Sun-Earth lagrange points (such as those occupied by SOHO and other observation satellites). If we could get spacecraft without maneuvering capability to perform that orbital transfer, we'd be much closer to living in a Star Trek-esque world.
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Forgive my ignorance in these highly technical matters, but when exactly did we start sending up Small Or Home Office satellites?
Re:Not Sun-Earth Lagrange points (Score:5, Funny)
Forgive my ignorance in these highly technical matters, but when exactly did we start sending up Small Or Home Office satellites?
I always wondered what that particular SOHO meant. Drove me nuts because I heard of the Solar and Heliospheric Observatory first.
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We didn't, but we did send up a Solar and Heliospheric Observatory.
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SOHO (SOlar and Heliospheric Observatory) is the primary NASA mission for observing the sun and solar flares.
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Right. This has nothing to do with Lagrange points.
This is related to the fact that the Earth is not perfectly spherical.
Re:Not Sun-Earth Lagrange points (Score:5, Interesting)
Re:Not Sun-Earth Lagrange points (Score:5, Interesting)
The gravitational effect of the moon is indeed very significant here, but it is periodic. (The net result is that the lunar perturbation makes a periodic change to the inclination of the orbit).
The drift in longitude is due to the Earth's non-sphericity, not the moon.
Re:Not Sun-Earth Lagrange points (Score:5, Interesting)
Re: (Score:3, Informative)
I know I've made some very poor decisions recently (Score:5, Funny)
After sending between 150,000 and 200,000 commands to the satellite to coax it back into service, Intelsat was forced to scrap its satellite-recovery efforts and to resort, on Monday, to a limited-duration effort to force the satellite to shut down its transponders. This was to be accomplished by sending a stronger series of signals designed to cause Galaxy 15's power system to malfunction and force a shutdown of the satellite's payload. That attempt, which Luxembourg-based, Washington-headquartered Intelsat had viewed as its last, best-understood option for Galaxy 15, was unsuccessful.
The last message from the satellite was "I'm sorry, Intelsat. I'm afraid I can't do that."
Re: (Score:3, Funny)
They forgot to use sudo.
$ reentry_burn
I'm sorry, Intelsat. I'm afraid I can't do that
$ sudo reentry_burn
Reentry burn initiated. Atmospheric entry in +00:15:00
Re:I know I've made some very poor decisions recen (Score:4, Insightful)
Atmoshperic entry from GEO 15 minutes after reentry burn? No way.
Re:I know I've made some very poor decisions recen (Score:5, Funny)
GEO /= GPS!!!! (Score:5, Informative)
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There are No GPS satellites in GEO. They have their own special orbits. The title is really, really wrong... http://en.wikipedia.org/wiki/Gps#Space_segment [wikipedia.org]
Um, well, actually there are. "The [WAAS] satellites also broadcast the same type of range information as normal GPS satellites, effectively increasing the number of satellites available for a position fix." http://en.wikipedia.org/wiki/Wide_Area_Augmentation_System [wikipedia.org] The title seems okay to me.
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The [WAAS] satellites also broadcast the same type of range information as normal GPS satellites, effectively increasing the number of satellites available for a position fix.
The WAAS satellites aren't merely another GPS satellites, it's entirely different. GPS signals have errors based on a variety of different variables (clock errors, ionosphere propagation variability, etc). The WAAS satellites broadcast a series of correction signals that account for these errors. The end effect is increased accuracy
Re:GEO /= GPS!!!! (Score:5, Informative)
You are correct that Galaxy 15 is not a Navstar (GPS) bird. But the title is not entirely correct, because WAAS (Wide Area Augmentation Service) is a signal which is sent to terrestrial receivers (i.e. your WAAS enabled GPS receiver) with position correction information. This information helps WAAS enabled GPS receivers to cancel out known (so called "systematic") errors that would otherwise affect your GPS receiver's positioning accuracy.
So while Galaxy 15 is not a GPS satellite, it does participate in delivering high accuracy geopositioning in concert with the actual GPS birds.
Cheap solution for the future... (Score:2)
Interference (Score:5, Funny)
Reminded me of this gem from NotAlwaysRight:
Apparently, it is possible for someone to be standing next to your satellite and cause interference, as long as the someone is another satellite. (But it isn't easy to tell them to stop... :P )
A funnel (Score:5, Funny)
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Generally speaking, we don't have any sort of rocket that can lift 100 tons up to 36,000km geosync orbit. I don't think that Saturn V can even do it. An Ares V might be able to do it, but of course we won't know until one is actually built. A typical geosync payload is 6 tons, or 12 tons to GTO.
dom
Re:A funnel (Score:5, Funny)
Short Circuit 3 (Score:2)
Lagrange point!? (Score:4, Informative)
LAGRANGE POINTS? Good God almighty? What in the holy heck are you talking about? That's just ridiculous. It's not going to go to the Lagrange points (any of them). If nothing else there's no maneuvering and so the semi-major axis is FIXED at essentially geosynchronous period. What will happen is that that it will drift at varying speeds on the order of fractions of degrees a day, speeding up as it goes towards the gravity wells, passing through at pretty high speeds, then climbing back out, slowing all the time. I haven't checked the TLEs but it will either oscillate back and forth in one of wells or pass from one to the other. Just like dozens of other "died in place" spacecraft that had exactly the same problem. Eventually as the inclination changes it might go over the side of the hill (since the wells are 3-dimensional) like Skynet II/9354. Look that one up, or DSCS II/Flight II/9432 TLEs and history, that's what it's going to do.
Brett
The inpact of the failure (Score:4, Informative)
Why not a ground based WAAS ... (Score:3, Informative)
... located at each individual airport. The airport already knows exactly where it is. It can receive the GPS signal and see how far off it is ... specifically for that airport. Then it would transmit that correction data in real time over a local UHF frequency that can serve approaching planes out to some distance (perhaps 100km). Nearby airports use different frequencies which get selected when the target airport is selected and GPS indicates they are within range.
They could also spend more money and put up a triangulation based TPS that would allow accurate terrestrial positioning independent of GPS. That would be in addition to final approach guidance systems. That is, of course, if you feel warm and cozy about having extra redundant systems serving the airplane you are on.
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Because the "WA" is "Wide Area". If you have one at an airport, it's an LAAS (Local Area Augmentation System), and they do exist.
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Yes, but it carries a WAAS signal which your consumer "GPS" unit uses to increase the accuracy it's measurements. So, if this gets too far out of position without shutting off, your consumer GPS might get confused. Exact impact hasn't been computed yet.
Re: (Score:3, Informative)
AFAIK, WAAS and other Satellite Based Augmentation Systems (SBAS) are basically differential-GPS done on a large scale. The position of the satellites doesn't matter, they're simply being used to distribute the correction data on a global scale. Other systems are ground-based and limited in their range.
Also, the usefulness of WAAS/SBAS is greatly diminished since selective available (SA) has been off for over a decade. One disadvantage is that it takes longer for an SBAS-using receiver to get a fix since it
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It has to do with the GPS system tangentially. It's part of the GCCS/WAAS system, which augments the GPS system for flight navigation purposes. It also relays TV signals.
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Correct, but it also carried a lot of other traffic. To call it a "GPS satellite" would be like calling it a "religious satellite" if it carries a televangelist channel, or a "financial satellite" if some bank uses it.
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Well, we don't really care about its other functions since they were moved to other C-band satellites without making the news. You can't move WAAS to a C-band-only satellite, you need the special L-band payload.
GPS doesn't work as well without it, but the real reason I used "Geostationary GPS" in the title was that Slashdot would not let me have enough characters in the title to say something more accurate.
Re:Title is wrong, not GPS (Score:4, Informative)
Re: (Score:2, Funny)
You've put me in a difficult situation explaining this to you since it appears you read the title but not the summaries or the articles, yet somehow knew that this is a commercial communications satellite. Here's a linky with details on how it *does* have something to do with GPS: http://www.gpsworld.com/gps/news/waas-broadcasting-satellite-having-problems-9810 [gpsworld.com]
Since I can't be sure you will read TFL, here's the first paragraph that you probably won't read either:
Intelsat S.A. announced they lost control of
Re:Title is wrong, not GPS (Score:5, Informative)
This is a commercial communications satellite that hasnothing to do with the Global Positioning System
It is not a GPS satellite, in that it is not part of the constellation of satellites that provide position reference. However, as TFA and the other links say, this satellite is one of only two that operate the Wide Area Augmentation System. WAAS uses ground-based GPS receiving stations with known positions to generate a correction signal which increases the accuracy of GPS position fixes to less than 25ft within North America and surrounding areas. Without WAAS, plain GPS can have error in the hundreds of feet. Without the accuracy provided by WAAS, GPS navigation cannot be used for instrument flight approaches - one of the most critical, important, and common uses of GPS today. If this satellite fails, the WAAS system will remain operational throughout most of its original coverage area - but will almost certainly fall outside the reliability limits required for instrument flight certification. It will be a very serious problem for many commercial users of GPS, and possibly for some military applications as well.
Re:Title is wrong, not GPS (Score:4, Funny)
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Well it's a good thing all of us pilots know how to fly planes without RNAV and GPS approaches. Right? You did pay attention in IFR training, right?
I am sure a lot of them are incapable of flying VFR without GPS now. Look at all those car drivers who end up in rivers because the GPS shows a way across.
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Everything is moving in orbit. If one satellite has a different speed from the others then it is moveing relative to them. In practice rocket motors are used for station keeping. If a motor (or the control system) fails then the satellite will not be able to hold station.