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GPS Accuracy Could Start Dropping In 2010
adamengst writes "A US Government Accountability Office report raises concerns about the Air Force's ability to modernize and maintain the constellation of satellites necessary to provide GPS services to military and civilian users. TidBITS looks at the situation and possible solutions."
There he is! No, wait...
The real concern is a major solar event - if they're having a big issue replacing one every other year, imagine if a major solar storm took out a dozen at once.
Have you been touched by his noodly appendage?
with land disputes. "Your fence is on my property" etc. We have had problems as it is with surveys in the last couple of years. It was blamed on poorly trained surveyors and some instances issues were settled in court particularly over contradicting reports and who pays for the cost of the surveys. In one instance 1/4 mile of new fence had to be moved at a cost of $10,000 and lawyer/surveyor fees of $25,000 over the fence been 5 feet out. The land in question later was sold for $60,000. What a waste of money over a silly pissing contest.
Why move to Europe? I mean, its not like they'll not be restricting the system so that it only works over Europe. Why not just buy a Galileo receiver (when they become available)?
Also, isn't Galileo supposed to be backwards compatible with GPS?
We all know what to do, but we don't know how to get re-elected once we have done it
Just your 1/50th of a cent?
I'm Catholic you insensitive clod! I can't use it!
.02Vc (Verizon cents)
Oooh, a new acronym!
RAFES - Redundant Arrays of Fucking Expensive Satellites.
John
A friends mom escaped the wreck of a 90ft Fish Packer as it hit the rocks at night in a passage with strong currents due to a problem caused by relying on GPS. It was due to something like how it derived the heading vs the direction of travel or some-such.
Moral of the story was that using static ground stations like LORAN, this would not have occurred. Anyhow, now ground stations have been dismantled and vessel's receivers scrapped and there is nothing groundbased to replace GPS with should GPS fail. High altitude communications aircraft seem viable; however, there again is a reliance on something that is not physically bolted down and easily fixable.
An interesting footnote is mentioned by Buckminster Fuller in his 50 year summation masterwork "Critical Path": on pages 186-7. The Americans started their radio-accurate mapping from Compass Island in Penobscot Bay in Maine, and proceeded by radio triangulation to work their way down to South America, across the Atlantic and up Africa to Europe. This was needed for accurately guiding bombers above the clouds, as the ground survey maps were often 10's of miles incorrect.
The Germans had done this as well for Europe and perhaps Russia, so when Berlin fell, the Russians went in early and took the German mapping data. Russia had radio-accurate maps of all of Europe and published data from the US, while the US did not have maps of Russia. This lead to the importance in the cold war of US spy planes and satellites for basic mapping for targeting ICBM's, including as suggested by Fuller a US presence in Iran and Afghanistan as radio triangulation bases. Russia performed massive deceptions of fake cities and so on to perpetuate this information gradient.
A normal event, sure. But a repeat of the 1859 solar flare would likely damage many satellites not in the Earth's shadow at the height of the impact. Is the whole GPS constellation set up to handle that type of event? Or would more than half the satellites go down in a hour?
Have you been touched by his noodly appendage?
Well, that wasn't really a cent sign. He might have meant it was just his 5 995 849.16 m/s.
A friends mom escaped the wreck of a 90ft Fish Packer as it hit the rocks at night in a passage with strong currents due to a problem caused by relying on GPS. It was due to something like how it derived the heading vs the direction of travel or some-such.
Something wrong there. Both LORAN and GPS only give position (GPS gives time too, but that doesn't help here). Direction of travel is determined in both systems by taking the difference in position over a known time interval. GPS can give heading by using the phase difference between receivers on different parts of the vessel, whereas the wavelength of LORAN was probably too long for that to work. Upshot is, a problem involving headings and direction of travel isn't the fault of GPS, and using LORAN would have been no defence. It may have been a problem with the GPS receiver software, but LORAN calculations could go wrong too. Most likely it was a navigator not understanding the systems they had.
Quidnam Latine loqui modo coepi?
Heh. Naming a bunch of things that orbit the earth after Galileo. Irony :-)
Repton.
They say that only an experienced wizard can do the tengu shuffle.