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Communications Earth Transportation

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."
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Geostationary GPS Satellite Galaxy 15 Out of Control

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  • Not necessarily... (Score:5, Interesting)

    by Penguinisto ( 415985 ) on Sunday May 09, 2010 @08:12PM (#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 LostCluster ( 625375 ) * on Sunday May 09, 2010 @08:23PM (#32150500)

    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.

  • by Anonymous Coward on Sunday May 09, 2010 @08:24PM (#32150508)

    I remember turning my big satellite dish towards galaxy sats. Trying to unscramble the pr0n channels. I sold all my equipment years ago but still miss the big monster and waiting on it to lock in to whatever satellite I was after.

    I nearly killed my wife with my C-Band satellite dish. She was on the riding lawnmower and I moved the dish to a satellite that required it to aim very low in the southern sky. She didnt see it moving in time as she was looking at the right front wheel because she thought it was getting low on air. A trip to the hospital with 15 stitches and a mild concussion and it was time to sell and buy a DirectTV dish. Looking back I should have just gotten rid of my wife. It would have been a better deal in the long run.

    Tuning... Tuning... Tuning... Tuning... G15 CH40 crap on tv tonight. Tuning... Tuning... Tuning... G17 CH25 Hell yeah porkys is on (dont remember what all channels but it was good times).

  • Light pressure (Score:5, Interesting)

    by Bruce Perens ( 3872 ) <bruce@perens.com> on Sunday May 09, 2010 @09:29PM (#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.
  • by Bruce Perens ( 3872 ) <bruce@perens.com> on Sunday May 09, 2010 @09:34PM (#32150892) Homepage Journal
    Well, it's a low-energy point along an orbit. Since you can't treat Earth as a point mass and it's not perfectly round or uniformly dense, there probably is a "three body" problem in this case. So, isn't it the same phenomenon, just a degenerate case?
  • by grumling ( 94709 ) on Sunday May 09, 2010 @10:09PM (#32151060) Homepage

    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.

  • by jfields026 ( 947589 ) on Sunday May 09, 2010 @10:24PM (#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 vlueboy ( 1799360 ) on Sunday May 09, 2010 @10:27PM (#32151152)

    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... we have almost no programming to use the technology we purchased. Over the air HD is hit or miss, and most people continue to use cable because lots of the new OtA power transmitters suck.

    I want cablecos to explain what my bill will look like the day Standard Definition gets truly "deprecated." It should force them to remove all those duplicate non-HD channels, or upgrade my free channels to their currently payfor HD clones at no extra cost --I seriously doubt the latter will be taken, but they can't justify pulling the plug like the US government did to analog TV across the country in June 2009.

    Years after first generation HDTV sets have arrived in stores and reached to reasonable prices, networks still do not transmit in HD even 1/2 of their programming (I'm not talking 10 year old classics, but stuff recorded recently on what should be all HD cameras by now.) Weekend sports and local news are HD in many channels, but makes up for only a few weekly hours in our 24*7 blocks. While all the 9-to-5 worker drones are too busy to notice, networks are chugging along at the same old cheap non-HD resolutions until the weekend fake-out. Whatever non-basic HD is out there comes at a premium price. The two big networks for Spanish-only immigrants have even less total HD programming. Cable-subsized television for local community programming has 0 HD programs even in New York city. With no HD deadline in sight, it seems we were all duped by LCD-manufacturers and cablecos. Our second generation HD LCD sets will have undergone slow pixel death by natural dimming before governments force all cameras in every local HD program to actually transmit in HD. meanwhile, it's cries from distortion and previously unnecessary stretching for all of us.

  • Re:Target practice? (Score:4, Interesting)

    by tagno25 ( 1518033 ) on Sunday May 09, 2010 @10:43PM (#32151228)
    Planetes [wikipedia.org] is a good example of what could happen if we leave space trash.
  • Re:Target practice? (Score:1, Interesting)

    by Anonymous Coward on Sunday May 09, 2010 @11:01PM (#32151338)

    Or better yet the Corrupt News Network.

  • by Geoffrey.landis ( 926948 ) on Sunday May 09, 2010 @11:35PM (#32151522) Homepage

    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.

  • Comment removed (Score:4, Interesting)

    by account_deleted ( 4530225 ) on Monday May 10, 2010 @03:07AM (#32152442)
    Comment removed based on user account deletion
  • Re:Target practice? (Score:4, Interesting)

    by YttriumOxide ( 837412 ) <yttriumox@gmai[ ]om ['l.c' in gap]> on Monday May 10, 2010 @07:28AM (#32153390) Homepage Journal

    Interesting idea... I do see several possible problems with it though...

    • Size: In order to be effective at "grabbing" the debris, it would need to be fairly large... anything small simply won't grab enough junk. "Large" would be a technical challenge, and possibly cause other problems floating around up there.
    • Water: The ISS doesn't have "waste water" as such... they recycle pretty much everything they can, and extremely effectively. There's no feasible way other than launching a whole lot of water up there, which is an expensive proposition.
    • Time: Related to "size" but basically, it'd take a very long time for this to have any measurable effect on all the junk up there.
    • Orbital decay: The idea of the orbit decaying as it picks up junk is of course fine (less through the added mass though, and more through the relative velocities as they impact), but I would be concerned about the maths of this. I get the feeling it'd come down and burn up WAY before it'd collected a useful amount of junk

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