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My SAM III Magnetometer Readings for Winterton, North Lincolnshire in England.


I bought this magnetometer way back in March 2019 were it just sat in the filing cabinet waiting for me to finish building. In May 2021, I spent 3 days finishing and testing the magnetometer. It's finally running - alerting me to possible Northern Light shows due to the fluctuations in magnetic field around Earth.


In November 2023, I noticed the Bx axis readings disappeared, following shortly later was the Bz axis. December, I lost the By axis. In January 2024, I dug the sensors up (as I buried them 1m into the ground) and found water had ingressed and ruined the setup. I therefore ordered 3 FG3-PRO sensors and circuitry and on 21st January 2024 the units were back up and running - in waterproof boxes above ground!

April 3rd, the FG3-Pro sensors from Greece were showing erratic readings since install. On April 8th, I ordered the original FG-3+ sensors from Slovenia and installed them when they arrived on 17th April 2024, I also double waterproof boxed them and buried them 1m down into the ground. Fingers crossed...

Thanks go to Witham Reeve for shipping it to me from Alaska...

Below is the live magnetometer trend from the sensors located in my back garden! When a geomagnetic storm starts - the magnetometer responds with spikes indicating unrest. As the storm strengthens the magnetometer spikes better... once the trend falls significantly in these lower latitudes there is a chance that we will see the aurora low in the Northern Horizon... don't forget, clear skies and no light pollution is required for best results... Good Luck!!!


This page automatically reloads the latest magnetogram every minute.

Sensor: 3-axis, X (North-South, blue), Y (East-West, red), and Z (Vertical, green) - Geographic Coordinate System

My SAM-III with 3 sensors commissioned 23rd May 2021. Re-commissioned 21st January 2024 after water damage (FG3 Pro sensors). Re-commissioned again with new FG-3+ sensors on 17th April 2024.


The horizontal scale is a 24-hour time scale in Coordinated Universal Time (UTC). Just above the horizontal axis are colored bars indicating the K-index for each period (this actually is a pseudo-K-index because it is calculated on each of the X, Y and Z components instead of the horizontal component [vector sum of X and Y]). The highest K-index of the three appears at the top of the chart. The colors of the K-index bars are: Green: K3 and below, Yellow: K4 and K5, and Red: K6 and above.


A red alarm bar may appear just below the horizontal axis. The alarm is triggered when the magnetic field fluctuations reach a preset threshold within 20 minutes. For the above chart, the threshold is K6. A rapidly changing field indicates high probability of visible and radio aurora.


The vertical scale shows magnetic induction (magnetic flux density, B) in nanoTeslas. The chart is normalized each day at 0000 UTC wherein the magnetic induction of all three components, Bx, By and Bz, are zeroed relative to the value at 2359:59 UTC the day before. The vertical scale is automatically adjusted (auto-scale).


The color of each trace is indicated for Bx (Blue), By (Red) and Bz (Green) in the lower-left corner of the chart.


The chart legend includes the Town and Country, Geographic Coordinates, date (dd.mm.yy) and time. Note: geomagnetic coordinates of the station are given at the top of this page.

Magnetogram updates every minute.