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Geostationary GPS Satellite Galaxy 15 Out of Control 379

Posted by timothy
from the geo-wobby dept.
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."
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Geostationary GPS Satellite Galaxy 15 Out of Control

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  • Bastard (Score:5, Funny)

    by oldhack (1037484) on Sunday May 09, 2010 @06:55PM (#32150330)
    Nuke the rogue satellite in the orbit.
  • by Joce640k (829181) on Sunday May 09, 2010 @06:55PM (#32150332) Homepage

    Haven't the military got some super satellite-busting weapon they've been dying to test?

    • by peragrin (659227) on Sunday May 09, 2010 @06:58PM (#32150342)

      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.

      • by Entropius (188861) on Sunday May 09, 2010 @07:02PM (#32150372)

        ... because a big debris cloud in orbit is a whole lot safer than one satellite in a known orbit.

        • 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.

          • Re: (Score:3, Insightful)

            by Entropius (188861)

            ... 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.)

          • by quanticle (843097)

            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.

          • by sjames (1099)

            Except that the debris could just as easily take those same networks off the system even longer if they strike the relevant satellite.

        • by Howitzer86 (964585) on Sunday May 09, 2010 @07:10PM (#32150440)
          I thought it would just fry the electronics with intense heat. Just how much debris would that create? Can't be much.
          • by hairyfeet (841228) <bassbeast1968@@@gmail...com> on Sunday May 09, 2010 @09:24PM (#32151138) Journal

            You have to remember even a pebble at the kinds of speeds you can get up there can be catastrophic. This is why we the people of this planet really need to be working on a strategy for cleaning all the crap leftover from dead and broken sats. As you can see here [treehugger.com] just the amount of useless dangerous shit DARPA is tracking is just unreal, and that don't count all the tiny fragments that can tear through you like a bullet.

            So while blowing it up would be a spectacularly bad idea, we do need to have a way to deal with dead crap in space. As we get more and more sats, and have to deal with more solar flares and other unexpected problems, this problem is only gonna get worse. Perhaps we need to offer a couple of billion dollar bounty for the one that solves this problem?

            • 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, Interesting)

            by tagno25 (1518033) on Sunday May 09, 2010 @09:43PM (#32151228)
            Planetes [wikipedia.org] is a good example of what could happen if we leave space trash.
        • by peragrin (659227)

          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.

        • by MadCow42 (243108)

          Why can't anti-satellite systems hit the target from ABOVE, and direct debrit towards re-entry?

          Madcow

          • Re:Target practice? (Score:5, Informative)

            by TooMuchToDo (882796) on Sunday May 09, 2010 @07:43PM (#32150612)
            *MORBOR*: That is not how orbital mechanics works!

            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.

            • Re: (Score:3, Funny)

              by Anonymous Coward

              "Morbo is not spelled that way!" - Morbo

        • Light pressure (Score:5, Interesting)

          by Bruce Perens (3872) <bruce@perens.com> on Sunday May 09, 2010 @08:29PM (#32150864) Homepage Journal
          Light doesn't just illuminate something. It has pressure. If you illuminate a satellite from the proper angle with less than the energy required to blow it apart, for long enough, you can change its orbit.
      • Re: (Score:3, Funny)

        by EdIII (1114411)

        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.

        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

    • by thms (1339227) on Sunday May 09, 2010 @07:40PM (#32150604)

      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.

    • 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.

  • by LostCluster (625375) * on Sunday May 09, 2010 @07:02PM (#32150376)

    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.

    • by ColdWetDog (752185) on Sunday May 09, 2010 @07:12PM (#32150444) Homepage
      And nothing of value was lost.
    • Not necessarily... (Score:5, Interesting)

      by Penguinisto (415985) on Sunday May 09, 2010 @07:12PM (#32150446) Journal

      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.

    • by MasterOfMagic (151058) on Sunday May 09, 2010 @08:03PM (#32150732) Journal

      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.

      • Re: (Score:3, Interesting)

        by grumling (94709)

        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.

      • Re: (Score:3, Informative)

        by LostCluster (625375) *

        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.

  • by Manhigh (148034) on Sunday May 09, 2010 @07:07PM (#32150404)

    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.

    • by FooAtWFU (699187)

      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).

      Forgive my ignorance in these highly technical matters, but when exactly did we start sending up Small Or Home Office satellites?

      • by snowgirl (978879) on Sunday May 09, 2010 @07:32PM (#32150552) Journal

        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).

        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.

      • by yotto (590067)

        We didn't, but we did send up a Solar and Heliospheric Observatory.

      • by quanticle (843097)

        SOHO (SOlar and Heliospheric Observatory) is the primary NASA mission for observing the sun and solar flares.

    • Re: (Score:3, Funny)

      by Bruce Perens (3872)
      Oops. These are not L1 and L2? I am having trouble imagining the physical mechanism for earth-relative libration point. There's no other mass and this is a phenomenon driven by the oblate shape of the earth?
    • by jfields026 (947589) on Sunday May 09, 2010 @09:24PM (#32151130)
      It has something to do with the mass of the Earth. These points line up pretty well with the Rocky Mountains and the Himalayas. These areas are known as gravity wells and all Geo satellites try to drift there. As operational satellites drift, they are command back into their orbital slot by their operators. Some satellite operators will purposely position their satellites at the wells as there is less fuel required to keep them in their orbital. Dead satellites drift towards the closet well, slingshot past them, and then come back. Occasionally they will swing back and forth between the two wells. It takes several months to swing back and forth. The satellites also gain inclination over time (15 years) before they hit a certain orbital point and then their inclination drifts back down to zero, and repeat. The inclination drift is said to be due to the Moon, however, it's tied the the satellites Right Ascension of the Ascending Node (RAAN), something that's independent of the Moon. Regardless, over time these satellites that die on the "Geo-belt" only really cross the operational satellites twice a day because of their inclination. US law requires satellite operators to dispose of their GEO satellites into a graveyard orbit before they die, but you can't really do that when it stops responding. http://en.wikipedia.org/wiki/Graveyard_orbit [wikipedia.org]
  • by MRe_nl (306212) on Sunday May 09, 2010 @07:07PM (#32150412)

    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."

  • GEO /= GPS!!!! (Score:5, Informative)

    by dev_alac (536560) on Sunday May 09, 2010 @07:45PM (#32150642)
    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]
    • Read about WAAS. Many consumer & professional GPS receivers use it to enhance the accuracy.
    • Re: (Score:3, Informative)

      by ebob (220513) *

      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.

      • Re: (Score:3, Informative)

        by Vellmont (569020)


        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)

      by flatulus (260854) on Sunday May 09, 2010 @09:31PM (#32151166)

      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.

  • Tin foil... lots of it.
  • by Arancaytar (966377) <arancaytar.ilyaran@gmail.com> on Sunday May 09, 2010 @08:05PM (#32150738) Homepage

    Reminded me of this gem from NotAlwaysRight:

    Customer: “I will have you know, son, I am a Gunnery Sergeant. I’ve worked with Hand Operated Radios for years and I’m telling you RIGHT NOWthere is someone standing next to your satellite with a d*** radio and it’s interfering with my signal. I demand you to get out there and tell them to stop.”

    Me: “Far be it from me to ever argue with my clients, but I will have to at this time. I understand that you’re a Gunny Sergeant and that you’ve operated HAM radios for years, but I know my satellite equipment, and it’s not possible for someone to be standing next to my satellite with a radio.”

    Customer: “Oh? Really, smart man? Why is that?”

    Me: “Because our satellites are in outer space."

    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)

    by falken0905 (624713) on Sunday May 09, 2010 @08:06PM (#32150748)
    Perhaps they can launch and rendezvous a 100 ton steel 'funnel' and fit it over the satellite thus preventing it from spewing tons of satellite pollution toward earth. In fact, such a device has already been built and is currently not being used. Bonus, it's currently located not all that far from Cape Canaveral and transport ships are located nearby.
    • Re: (Score:3, Informative)

      by Anonymous Coward

      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

  • Number 5 got upgraded, and now is runing amok over our heads.
  • Lagrange point!? (Score:4, Informative)

    by Brett Buck (811747) on Monday May 10, 2010 @02:19AM (#32152484)

    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."

        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

           

  • by batistuta (1794636) on Monday May 10, 2010 @04:59AM (#32153020)
    WASS is used to provide corrections to upper atmospheric disturbances in the GPS signal. It works like this: you have a lot of beacons on ground, mostly close to the shore but pretty much everywhere in the country. These stations know *exactly* where they are, but they anyway measure their position via GPS. By looking at the difference between what GPS says and what they know, they calculate the effect of these atmospheric disturbances. These are uploaded to a central system and get in turn broadcasted via WASS. WASS signals get used mostly by air and maritime vehicles in the North America. Europe has something similar called EGNOS, that depending on the country it could be used with limited advantage on terrestrial measurements. In Germany for instance, the angle to EGNOS is about 20 degrees which makes it almost impossible to capture free-line-of-sight by anyone that is not airborne or in open waters. Now back to the issue. One WASS satellite is failing. There are two WASS satellites and we are fortunate that the one about to fail is not the most important one. This link has some nice images showing the coverage. Sorry for copy-pasting, it's my first post and don't know how to add tags yet. http://www.gpsworld.com/gnss-system/augmentation-assistance/news/failure-imminent-waas-geo-satellite-9841 [gpsworld.com] The problem is that airspace people don't like single point of failure so having one satellite only is a yellow lamp. How this will affect air traffic is still to be seen. GPS accuracy is about 16m with a good view, and when traveling 200 mph during approach, this is not crucial if you ask me. Maritime is something different. You don't wanna sail in Sweden and hit an underground island because you are 10m too far left. For final approach to runway and landing WASS has never been an enabling technology, so business as usual. The US will either replace the satellite or bring the functionality to another one. Until then, people must know that WASS could be out for a few seconds every once in a while. Nothing new really. None of us here will probably feel anything particular happening in the sky.
  • by Skapare (16644) on Monday May 10, 2010 @06:20AM (#32153360) Homepage

    ... 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.

    • Re: (Score:3, Informative)

      by russotto (537200)

      Why not a ground based WAAS located at each individual airport.

      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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