The geomagnetic storm that generated the spectacular aurora visible throughout Italy on the night of Friday 10 May 2024 continues to shake the Earth’s magnetosphere and could persist in the coming days with new auroras in unusual locations. Here’s where they might occur.
The most confident were awaiting it with enthusiasm, especially those who missed the fascinating spectacle of the dawn that crossed the skies of Italy on the night of Friday 10 May 2024. But in the end, on the night between 11 and 12 May 2024only a lucky few, especially in the North, they were able to observe it again. Of course, it was not as intense as that of the previous night, when in various regions of Italy the sky was tinged with a suggestive colored light, between pink and violet (here we have collected the most beautiful photos).
On the other hand, the forecasts had left open the hypothesis of a possible encore on these nightsgiven that what generated it, one geomagnetic storm very intense (grade G4 on a scale that reaches G5), it has not yet completely subsided, but is going through its peak in recent days.
However, many they were disappointed: from the United States several users on social media have posted photos of the dark sky without the long-awaited dawnothers posted shots in which only a faint colored light was visible.
Earth hit by acute geomagnetic storm, opens “crack” in magnetosphere: what happens
DOLOMITES VAL GARDENA | A scene taken from the livestream webcam during the night between Saturday 11th and Sunday 12th May
How the geomagnetic storm is evolving
Friday 10 May an alert from Space Weather Prediction Center (SWPC) and the National Oceanic and Atmospheric Administration (NOAA) warned that a geomagnetic storm would hit the Earth in the following days. Specifically, the warning made it clear that it would be a severe geomagnetic storm.
It was classified as G4 grade, practically almost the maximum foreseen by the scale used to measure the intensity of geomagnetic storms and which does not foresee other levels beyond G5. In this specific case, SWPC and NOAA explained that the origin was “a large and complex sunspot cluster (NOAA Region 3664)”, equal to 17 times the diameter of the Earth. Here you can see what a sunspot looks like.
Such an intense geomagnetic storm it hasn’t happened since 2005: so much so that the forecasts for these days had also taken into account the possibility of interference with GPS, electricity grids, space vehicles and other technologies. On Saturday 11 May, a new update from SWPC and NOAA clarified that the storm had even reached levels that could be classified as maximum G5.
According to the latest update, published on the official SWPC website at 17:54 UTC on Saturday 11 May 2024, the coronal mass ejections (CME)origin of the storm, also occurred on Saturday 11 May and is expected to others will arrive on Earth also during Sunday 12 May. This is why it is possible that they will occur new aurorasfor example NOAA predicts possible ones in the Northern United States and “perhaps south of Alabama and northern California”.
The causes of the geomagnetic storm that generated the aurora
As we explained here, the aurora is a phenomenon of colored lights, a spectrum ranging from red to violetwhich manifests itself as a result of thegas excitation present in the other part of the atmosphere, beyond the 50 km away from the earth’s surface. Usually, the traditional aurora is the one that occurs in the heavens Northern countries and only at certain times of the year, but what we have seen in recent days is an even rarer event.
If in traditional auroras the gases in the atmosphere are excited by the particles of solar winds, in those we have witnessed in recent days in Italy – but have also been visible elsewhere – the cause is this intense geomagnetic storm.
This is a natural phenomenon that occurs when i solar winds – the set of charged particles emitted by the coronal mass ejections (CME) that occur around the Sun – arrive on Earth, interfering with the outermost part of the magnetosphere that surrounds our Planet and creating these phenomena visible from the Earth’s surface.
