What are Solar Flares, and What's Been Happening on the Sun Lately? Scientists Weigh In

A sudden surge of 'violent' activity on the Sun has placed solar flares in the headlines as scientists track one of the most active sunspot regions seen in years. Many who are unfamiliar with the phenomena are asking: 'What are solar flares, and what exactly is happening on the sun?'

Solar flares are intense, localised bursts of electromagnetic radiation that erupt from the Sun's atmosphere, usually forming in areas known as active regions. They are driven by the rapid release of stored magnetic energy, which accelerates charged particles in surrounding plasma and produces radiation across the full electromagnetic spectrum. These events often occur alongside other solar phenomena, although a flare can happen without additional eruptions.

The radiation released during a flare follows a recognisable sequence that scientists have studied for decades. This pattern begins with a precursor phase, followed by an impulsive phase dominated by particle acceleration, and then a gradual phase as hot plasma cools through radiation and energy conduction. Some flares also show a late extreme ultraviolet phase that remains unexplained.

Why Solar Flares Happen

The Sun's surface and atmosphere are threaded with powerful magnetic fields that constantly shift and twist. When magnetic field lines in active regions become too tangled, they can snap back into alignment in a sudden release of energy. This process produces solar flares and can also send large clouds of plasma into space.

These events are not evenly spread over time and instead follow a repeating cycle. Solar activity rises and falls over an 11-year period linked to changes in the Sun's magnetic field. During the most active stage, known as solar maximum, sunspots, flares, and coronal mass ejections become more frequent and more intense.

A Monster Sunspot Emerges

Scientists are currently watching a fast-growing sunspot known as region 4366, which appeared only days ago and expanded rapidly. It has already reached roughly half the size of the sunspot linked to the Carrington Event of September 1859, the most destructive geomagnetic storm on record. Its sudden growth has made the region highly unstable.

Between Sunday and Monday on 1–2 February, region 4366 produced more than 20 solar flares in just 24 hours. These included at least 23 M-class flares and four X-class flares, the strongest category recorded by NASA. Such concentrated activity over a short period is unusual and closely monitored.

The Strongest Flare in Years

The peak of this activity came at 6:57 pm EST on Sunday, when the sunspot released an X8.1 solar flare. According to the Space Weather Prediction Center, this was the strongest solar flare observed since an X9.0 eruption in October 2024. The flare immediately affected parts of near-Earth space.

Reports from Spaceweather.com confirmed partial radio blackouts across the South Pacific following the eruption. The flare also launched a slower-moving coronal mass ejection in the direction of Earth. This cloud of charged plasma is now being tracked as it moves through space.

Potential Effects on Earth

The Space Weather Prediction Center expects the coronal mass ejection to pass by Earth on 5 February. Current forecasts suggest it will narrowly miss the planet, although a slight impact remains possible. Even a minor encounter could have visible effects.

If the plasma cloud clips Earth, charged particles would be guided towards the magnetic poles. This process could produce bright auroras, potentially visible at lower latitudes than usual. Elevated geomagnetic activity has already been flagged as a possibility, though certainty remains limited.