What if GPS and its Chinese, European and Russian counterparts were to go down because of some cosmic catastrophe, most likely a huge solar flare frying the satellites. Such as the one in 1859 that, at that time, caused some damage to telegraph systems, because of the very high voltages, induced by the very fast changes it produced in the Earth magnetic field, in the very long loops formed by the long-distance telegraph lines. But that was all the important electric equipment that was vulnerable to such flares then. Things have changed.
We could have had a taste of this earlier this month, when not a huge flare, but an obscure, as yet undisclosed problem (that is looking worse as time goes by without a forthcoming explanation from those in charge) that caused the European equivalent of GPS, known as GALILEO, to go out, completely, for about one whole week. Fortunately, most equipment that uses it, from cell phones to the controls of nation-wide power distribution grids, switched automatically to GPS and things kept going as usual and people hardly noticed:
https://www.wired.com/story/galileo-satellite-outage-gps/
But what if we had the kind of problem that can bring down GPS and the other satellite systems, from positioning and timing (e.g., GPS, GALILEO, GLONASS and Beidu) to weather monitoring and a myriad other applications of artificial satellites in this day and age?
What will happen is this: until the satellites are replaced, because they cannot be repaired in orbit, there will be no navigation assistance to airplanes, ships, delivery trucks, ambulances, etc. No Internet, that depends both on computer servers and on GPS satellites and their like to keep working in good and synchronous order, so no Web either, no Internet of Things, no smart self-driving vehicles, no effective control of power grids, and so on and so forth. Of course, the power grids would not work anyways, because there would be massive black outs caused by the transformer substations burning down, if nothing else. So most industrial equipment, including those needed to make replacement satellites, will be left off line, and the world will have to get back to a semblance of civilized order in the middle of a huge humanitarian crisis. Without GPS and its counterparts to help figure things out.
While a few of the GPS-like satellites might survive, (for example , and with great good luck, those on the night side, during the few days, twice a year, when they are in deepest, longest eclipse) it is unlikely that there will be enough of these for the various software applications that use their signals to find position and time to be able to do much, if anything, with them, because they are generally designed to work with as many satellites as possible, and that means at least more than 24 of them available at any time.
Such is the warning the GALILEO shutdown has given the world. But the world has hardly noticed. Have you?
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