In the stillness of 1st September 2025, the Sun unleashed a rare and dramatic event  –  two successive coronal mass ejections (CMEs), one chasing and engulfing the other. This cosmic “cannibal storm” has now reached Earth, and set the stage for a night of vibrant aurora and subtle terrestrial reverberations. With a bit of luck you would have seen some of it. A G2–G3 (possibly G4) geomagnetic storm

This twin-edged solar outburst was born from sunspot AR4199, which erupted on August 30. The storm reached our planet September 1st into the early hours of September 2

NOAA’s Space Weather Prediction Centre issued a Moderate to Strong geomagnetic storm watch (G2–G3), with the potential for G4-level severity – a threshold that brings rare intensity to the night’s sky.

Astronomically speaking, the CME’s arrival compressed Earth’s day-side magnetosphere and extended its magnetotail – an energetic dance of magnetic reconnection that channels many terawatts of energy into the upper atmosphere. These induced currents ripple through the ionosphere, increasing electron density particularly in high latitudes. The ionospheric plasma becomes a stage for auroral light, and HF radio waves can experience absorption, leading to shortwave communication blackouts.
Even at Earth’s surface, geomagnetically induced currents (GICs) stir in pipelines and power grids. While today’s storm did not cause widespread interference, it nudged our technological veins all the same.

Aside from aurora borealis, any geomagnetic storm may – at least modestly – disrupt satellites, tweak HF radio propagation, and momentarily ruffle GPS accuracy. Satellite operators and power grid managers are always notified to brace for these episodic fluctuations.

This solar activity arrived amid Solar Cycle 25’s growing outbursts. As this solar activity surges, the Sun’s tangled magnetism repels cosmic rays, leading to a measured drop in atmospheric radiation.

And though the Carrington Event of September 1859 remains unmatched in historical ferocity, the current “cannibal storm” offers a fresh reminder of our star’s dynamic temperament – capable of disrupting terrestrial systems or, if conditions are right, painting the night sky in shimmering colours – which are a sight worth going to see if you can.

Earth is currently experiencing elevated solar activity. Coronal mass ejections (CMEs) and solar flares have increased in frequency, impacting the magnetosphere with geomagnetic storms. These disturbances compress the magnetosphere, drive currents in the ionosphere, and subtly alter Earth’s electromagnetic environment. Plasma bursts from the Sun contribute to these effects, producing variations in the geomagnetic field that can propagate to the surface. Creating sights and events that also effect you, as the human being is a torus of electromagnet balance of the utmost delicacy – as are all living beings.