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Intelsat-7 Lost In Space
freitasm writes "The Intelsat-7 was reported lost today. The satellite covered the continental U.S., Alaska, Hawaii, Canada, Central America, and parts of South America. It was used to provide digital programming in the Cable Zone, direct-to-user programming, and Internet and data applications to North/Central/South America.
The company is already working on the launch of Intelsat-8, scheduled for 17 December."
Newspeak for power failure?
Intelsat has made alternative capacity available to most of its IA-7 customers, many of whom have already had their services restored.
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You can read more info about this here
I'm sure that it won't be a huge deal. Our recievers have about 20 satellites programmed in them. I'm sure better/bigger stations or cable companies have more options.
The station that I work at doesn't use IA7. Now if Intelsat 5/6 or Galaxy 4 dies, then we might have a problem.
This ComputerWeekly's article says there was a failure of a communications satellite over the weekend that knocked out US broadband services supplied by StarBand Communications. The total loss of Intelsat's Americas-7 satelllite forced StarBand to move customers to a different satellite. StarBand did not say how many subscribers were affected, but is attempting to provide them with a temporary dial-up service.
Ant(Dude) @ Quality Foraged Links (AQFL.net) & The Ant Farm (antfarm.ma.cx / antfarm.home.dhs.org).
ABCNEWSABSAT
Excerpt
Intelsat has declared IA-7 "a total loss" according to Ramu Potarazu, the Chief Operating Officer for Intelsat. They are not giving any reason for the failure as of yet. At approx 0222 EST Sunday 11.28.04, they had an electrical short of some kind on Bus 1 and eight minutes later lost telemetry to the spacecraft according to Intelsat engineer Kevin Maloy. There were no station-keeping maneuvers being done at the time, Maloy said. IA-7 was located at 129 degrees West longitude.
Now I'm the grandest Tiger in the Jungle!
People without motorised dishes are mostly on DirectTV or Dish Network. The dish networks setup that we have here is pointed at two or more satellites. I'm not sure about the mechanics of it, but I am pretty sure it recieves 3 or 4 satellites. They would probably still have some major issues if they lost a satellite, probably with ppv and stuff like that, but who knows. They would certainly be able to provide at least some limited amount of service.
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No -- the satellites would probably have to be less than 1 degree apart. DirecTV does this, I believe, for normal operations, but IA7 is not a "managed" service like DirecTV. An earlier link mentions that the alternative satellite is about 25 degrees apart, so not only would you have to repoint your dish, you'd have to reset all the transponders/frequencies in your receiver, since those would have changed as well.
When something like this happens, they often see anomalous telemetry readings before the complete failure of the spacecraft. For example, main power bus current goes from 10A to 200A and main power bus voltage starts going down, down, down. The engineering telemetry link on a geosynchronous spacecraft is usually monitored 24/7 by the spacecraft's control center.
Mea navis aericumbens anguillis abundat
No company voluntarily "loses" a multi-million dollar functional asset. If it's still got functional transponders, they'll keep using it.
As for your other point - when possible, close to end-of-life, they try to move geosync birds to a super-synchronous (above the geosync plane) orbit, which will eventually cause them to migrate to nodal points safely out of the way of the remaining commercial satellites. This is often accomplished by a thruster burn that exhausts the remaining fuel in the tanks (preventing later tank explosions after thermal control is lost). If the satellite fails before planned end-of-life (usually determined by available fuel or power), it will end up in a figure-8 orbit roughly centered on the equator, and will slowly drift East or West depending on whether it was low or high, causing collision-avoidance issues for the rest of the geostationary com birds out there.
There's a lot of reference material out there - give it a read.
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It's big enough that the Air Force can track it on radar and keep it in their catalog of orbiting space junk. If there is a danger of a collision, they can send a warning to the owner of the other satellite so they can take evasive action.
Mea navis aericumbens anguillis abundat
For some locations, i.e. Alaska, there are no other Ku band satellites in range. Ku is the band that the satellite internet providers use. For those remote folks who rely on satellite to get access, their only alternative may now be dial-up.
See StarBand's note on the right-hand side of their page: "we are working to provide our customers with temporary dial-up service."
From past failures of geosynchronous communications satellites, there appear to be several classes of users. The people who pay the most, get guaranteed service and are quickly switched to a transponder on another satellite. The people who pay the least, lose their service and have to find another satellite, if any, that has unused capacity.
Mea navis aericumbens anguillis abundat
Include Spice, Playboy, and TEN.
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If you're not outraged, then you're not paying attention.
Actually both Dish and DTV have satellites in orbit that they aren't using that they referr to as in-orbit spares. To allow for just such an emergency.
Uhm ... nope. ... both north/south and east/west. They do station keeping burns about every 2-4 weeks on average to keep it within their 0.5 degree longitudinal slot.
... not just the payload ... then it will drift through the belt and eventually settle about one of 2 stable points. The inclination will also increase to about 15 degrees.
Geostationary satellites perform active stationkeeping
Solar raditation pressure, 3rd body perturbations (mostly the moon) and the irregular shape of the earth all perturb the orbit. So if they've lost everything on this bird
I agree that most commercial communications satellites are probably monitored on a regular, if not continuous, basis. I further agree that many anomalies have warning signs leading up to the failure that can give some indication of a pending problem. However, I have encountered many anomalies that provided no warning signs. In the power area, solar array degradation or degrading battery performance might show the signs you suggest, but there are critical failure modes associated with power distribution that can fail catastrophically with no notice. I am somewhat surprised that the design afforded no redundancy to mitigate such a failure, but you can't protect against everything. Sounds like a pretty freak occurrence to me.