On Wed, 25 Oct 2006 06:44:32 -0700, Ron Wanttaja
wrote in
:

On Wed, 25 Oct 2006 11:12:07 GMT, Larry Dighera wrote:

How was such a clash missed? Because GPS receivers only became common
during a period of low solar activity. By 2011 solar flares will reach
the peak of their cycle and receivers will likely fail.

The sun is on an 11-year cycle. If 2011 is the date of the max (and we are
apparently in the minimum now), the LAST max was about 2000.

Of course, natural phenomena can be somewhat erratic, but you astute
analysis seems relatively consistent with International Space
Environment Service observations/projections:
http://www.sec.noaa.gov/SolarCycle/

Unless the author believes that GPS receivers only became common after
2000, the user community has already been through one solar max period.

Apparently it was Alessandro Cerruti of Cornell University who raised
the concern, not the New Scientist author. But, you are correct about
having used GPS during the 2000 - 2003 peak period. I don't recall
any anomalous GPS behavior back then, but I do recall a solar storm
that caused my garage door opener to spontaneously open and close the
door repeatedly one day.