While solar storms are responsible for generating beautiful aurora displays in our night sky, they're also a cause of concern for astronauts, satellite companies and engineers alike.
The heightened displays of aurora we've seen this week, 18–20 January 2026, were caused by one such solar storm, and it was one of the most severe and intense on record.
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As a result, the European Space Agency (ESA) says its Space Weather Office is monitoring the event, gathering data and investigating the storm's effect on satellite and navigation systems.
ESA has also said that close monitoring of such space weather events is vital to ensure the upcoming Artemis II mission has a safe passage to the Moon and back.
A severe solar storm
The aurora displays seen this week were generated by an X-class solar flare, 'X-class' denoting it as the most extreme kind of solar flare.
The flare erupted from the Sun on 18 January 2026, along with a coronal mass ejection.
Solar flares have the potential to release as much energy as a billion atomic bombs, according to the European Space Agency.
Once a flare has erupted, electromagnetic waves from the Sun travel at the speed of light and hit Earth eight minutes later (since the Sun is eight lightminutes from Earth).
These waves are so powerful, they can disrupt radio transmissions and navigation systems and even have the potential to harm astronauts and spacecraft.
A flare is often accompanied by a coronal mass ejection, which is an eruption of ionised gas from the Sun's corona, its outer layer.
This generates a powerful 'solar wind' of charged particles that slams into Earth, reacts with atoms in our atmosphere and generates the aurora.
The European Space Agency says its Space Weather Office is monitoring the 18 January event.
"An X-class solar flare was detected on 18 January, at 18:09 UTC. The Sun’s activity recently crossed the peak of its current solar cycle but is still very active," ESA says.
"Our models predicted that the CME would travel towards the Earth at a speed estimated initially at 1,400 km/s, but the arrival at Earth after 25 hours indicates a speed closer to about 1,700 km/s."
ESA says the event peaked at 19:15 UTC on 19 January 2026, reaching 'severe' levels and making it one of the most intense radiation storms recorded.
What's more, ESA says events like this will need to be monitored in order to keep safe the astronaut crew of the Artemis II mission to the Moon, which could launch in a matter of weeks.
"Auroras have been observed all over Europe, even at lower latitudes than usual," ESA says. "Continued high levels of space weather activity are anticipated over the coming days."
If you captured images of the aurora, share them with us and they could feature in a future issue of BBC Sky at Night Magazine
