NavList:

Robert, as Richard Langley says, selective availability has been gone for 13 years. Of course, one could always argue that there is a "top secret" equivalent hidden in there somewhere. From a practical perspective, even if we consider such possibilities, the Russian Glonass system provides an entirely independent equivalent to the US GPS. Most smartphones have included Glonass-capable chipsets for nearly two years.

By the way, I would argue that this article is misleading simply because it is late. This is already nearly solar maximum. Predicting solar maximum is difficult and even the definition is somewhat fuzzy, but the peak of the average sunspot number will almost certainly occur this year, and it shouldn't be much different from what it is right now. It may be below the spike that occurred over a year ago. This has been a very weak sunspot cycle. There is no real new "threat" to GPS signals from solar activity this year. It's more of the same. Of course, there's always the possibility of some major flare above and beyond the usual norm of sunspot maximum.

-FER

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