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    Re: Susceptibility of GPS to CME, Rationale for CN?
    From: Brad Morris
    Date: 2018 Sep 30, 21:38 -0400
    Hi Francis

    As Bob indicated, the watches should be in an insulator, and then enclosed in the metal faraday cage.  

    Is the top of the thermos plastic?  Then the faraday cage isn't complete.  Are the watches touching any metal of the thermos?  Then the insulator just isn't.


    On Sun, Sep 30, 2018, 9:29 PM Francis Upchurch <NoReply_Upchurch@fer3.com> wrote:

    Does CME affect quartz watches? I keep my 4 cheap backups in a thermos flask stowed in a metal box ("Faraday cage").Should be safe?
    I knew I might  find a practical use for my mechanical Invicta watch (cheap Rolex Submariner copy)  which keeps regular time + 4-8 secs per day over the last 2 years.
    On the philosophy of time. Enjoy life and do it now. It is later than you think!
    -----Original Message-----
    From: NavList@fer3.com [mailto:NavList@fer3.com] On Behalf Of Richard B. Langley
    Sent: 29 September 2018 13:46
    To: francisupchurch---.com
    Subject: [NavList] Re: Susceptibility of GPS to CME, Rationale for CN?
    " The paucity of precise data from prior solar cycles may limit your ability to predict future levels of activity."
    It's impossible to predict when a strong solar flare or CME large enough to disrupt GNSS might occur. They can even strike near the minimum of the roughly 11-year solar cycle. Most outbursts are not severe enough to prevent GNSS being used but simply reduce positioning accuracy with the vertical coordinate (as is always the case) being a few times worse than the horizontal coordinates. Potentially more impactful are strong solar radio storms, which drown out the GPS signals. NOAA reported on such a storm in December 2006 here: https://web.archive.org/web/20071213212715/http://www.noaanews.noaa.gov/stories2007/s2831.htm (from the "Wayback Machine" as the original item is missing or got moved on the NOAA site).
    Much more impactful would be a repeat of the 1859 Carrington Event: https://science.nasa.gov/science-news/science-at-nasa/2008/06may_carringtonflare
    -- Richard Langley
    [plain text auto-generated]
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