V interesting indeed LS
One of the many school projects that I am currently working on has introduced me to the geomagnetic effects of space weather.
One measure of geomagnetic activity calculates the horizontal perturbations to the Earth’s own magnetic field and is called the ap index, which samples every 3hrs and records activity from nothing 0 to a maximum of 400. In March of this year magnetic storms with an
ap index ≤40 occurred and were mainly isolated intervals, due to the influence of high speed solar winds streams from the coronal holes in the Sun’s atmosphere.
However, two days before St Patricks Day (17032013) a moderately intense but long duration solar flare erupted and launched a CME (Coronal mass eruption) towards earth and travelling at over 3,000,000kmph it arrived on St Patricks Day and the result was the largest geomagnetic storm since November last year, when they had been unseasonably high storms, with the
ap index staying above storm level for over 18 hours, peaking at 110, knocking out two GPS satellites and tripping power grids in N America. This was also the reason the aurorae could be seen as far south as the Isle of Man, which I posted about
http://micronavigation.com/forum/index.php?topic=524.msg3730#msg3730