ESA's Swarm Bravo satellite was perfectly positioned to measure Earth's changing magnetic field during the large geomagnetic storm of 10-11 May 2024. In this animation, shades of red indicate areas where the magnetic field is stronger, while blues show it weakening, over time.
In the days leading up to 10 May, there is moderate geomagnetic activity at the poles, before the geomagnetic storm begins and deep reds extend down across the whole of Northern Europe and up as far as New Zealand. Meanwhile, mid-latitudes see a significant weakening of the magnetic field, as indicated by the deep blues.
The Swarm constellation is constantly monitoring changes to Earth’s magnetic field, which gives us information about the processes going on deep within Earth’s core all the way to the outer stretches of the atmosphere.