Research Unveils Secrets Behind Ireland’s Surprise Solar Storm

The solar storm that dazzled skies as far south as Kerry on April 23 and 24, 2023, caught scientists by surprise — and now new research is uncovering why.

Initially, the Sun’s blast, called a coronal mass ejection (CME), looked mild. It wasn’t especially fast or massive, and the preceding solar flare was weak. Yet, the resulting geomagnetic storm was intense.

Thanks to data from five NASA heliophysics spacecraft, researchers tracked the CME from its birth on the Sun to its arrival at Earth. They discovered a nearby coronal hole — a fast-streaming solar wind region — pushed and rotated the CME, steering it closer to Earth’s orbit and turning its magnetic fields opposite to our planet’s.

This magnetic alignment allowed a surge of solar energy to pour into Earth’s magnetic shield, intensifying the storm far beyond initial expectations.

At the same time, NASA’s GOLD mission revealed a surprising drop in temperature in Earth’s middle thermosphere after the storm—cooling by up to nearly 200°F. This impacts how much drag satellites experience, meaning satellites and space debris may orbit longer, increasing collision risks.

On the prediction front, researchers are making strides with machine learning tools like GeoCME, trained on solar images from NASA and ESA satellites. These models are showing high accuracy in forecasting which CMEs will trigger geomagnetic storms, promising better early warnings for our critical technologies.

Finally, during a massive storm in May 2024, NASA’s STEREO-A spacecraft — positioned closer to the Sun than ever before — demonstrated how placing sensors nearer the solar blast could extend warning times by over two hours, a vital boost for protecting Earth’s infrastructure.