NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Susceptibility of GPS to CME, Rationale for CN?
From: Francis Upchurch
Date: 2018 Sep 30, 06:40 +0100
From: Francis Upchurch
Date: 2018 Sep 30, 06:40 +0100
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! Francis -----Original Message----- From: NavList@fer3.com [mailto:NavList@fer3.com] On Behalf Of Richard B. Langley Sent: 29 September 2018 13:46 To: francisupchurch@gmail.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] ---------------------------------------------------------------- NavList message boards and member settings: http://fer3.com/NavList Members may optionally receive posts by email. To cancel email delivery, send a message to NoMail[at]fer3.com ---------------------------------------------------------------- ---------------------------------------------------------------- : http://fer3.com/arc/m2.aspx/Susceptibility-GPS-CME-Rationale-for-CN-Langley-sep-2018-g42938