Bengaluru: The Sun may be giving scientists a warning before unleashing some of its most powerful eruptions. Researchers studying data from India’s Aditya-L1 solar mission have identified small, short-lived brightenings in the Sun’s atmosphere that appear in the hours before major solar flares.
The findings suggest that these small energy releases are not random. They tend to appear close to the region where a major flare subsequently erupts, offering scientists a potential new way of recognising the early stages of a solar eruption.
The study was led by researchers from the Manipal Centre for Natural Sciences (MCNS) and Manipal Academy of Higher Education, in collaboration with scientists from the Indian Space Research Organisation (ISRO), the Department of Space and other academic institutions. The research has been published in the Monthly Notices of the Royal Astronomical Society.
The Sun may be showing its hand early
Solar flares are sudden and powerful releases of energy from the Sun.
They can send intense electromagnetic radiation and energetic particles into space. When major solar eruptions are directed towards Earth, they can affect radio communications, satellite operations, navigation systems and other technologies that modern society depends on.
Predicting exactly when a major flare will occur has remained difficult.
Scientists know that powerful flares are closely connected to the Sun’s magnetic fields, particularly in active regions around sunspots. But identifying the precise moment when stored magnetic energy will suddenly be released remains a major challenge.
The new study provides an important clue.
Tiny flashes appear before the big eruption
The researchers identified small, short-lived brightening events in the Sun’s atmosphere before major flares.
These events were observed in active regions during the hours leading up to the larger eruptions.
More importantly, several of the small brightenings appeared close to the exact location where the major flare later developed.
That pattern suggests that the Sun’s atmosphere may undergo a series of smaller energy releases before reaching the point at which a much larger eruption becomes possible.
Scientists refer to these small events as pre-flare transient events.
Their repeated appearance could provide a valuable signal for identifying an active region that is becoming increasingly unstable.
Aditya-L1 helped scientists see the changes
The discovery was possible because Aditya-L1 can continuously observe the Sun from a special location between Earth and the Sun.
India’s first dedicated solar observatory is positioned at the Sun-Earth Lagrange Point 1 (L1), approximately 1.5 million kilometres from Earth.
From there, the spacecraft can maintain an uninterrupted view of the Sun, allowing researchers to study solar activity across different wavelengths.
For this study, scientists combined observations from three instruments aboard the spacecraft.
The Solar Ultraviolet Imaging Telescope (SUIT) observed the Sun in near-ultraviolet wavelengths, while the Solar Low Energy X-ray Spectrometer (SoLEXS) and High Energy L1 Orbiting X-ray Spectrometer (HEL1OS) recorded X-ray emissions associated with energetic activity in the solar corona.
Bringing these observations together allowed researchers to connect activity in the lower solar atmosphere with energy release higher up in the corona.
Why ultraviolet observations matter
One of the important advantages of Aditya-L1 is its ability to observe the Sun in wavelengths that are difficult to study from the ground.
Earth’s atmosphere absorbs much of the ultraviolet radiation arriving from space.
SUIT can observe the Sun through 11 near-ultraviolet filters, allowing researchers to examine different layers of the solar atmosphere, from the upper photosphere to the chromosphere.
This provides a more detailed picture of what happens before a flare.
When combined with X-ray observations, the data can show how small-scale activity lower in the atmosphere is connected to the release of much larger amounts of energy in the corona.
The magnetic field could be slowly losing stability
The researchers believe the repeated small energy releases may gradually destabilise the magnetic field in an active solar region.
The Sun’s magnetic field stores enormous amounts of energy.
When the magnetic configuration becomes unstable, that stored energy can be released suddenly, producing a solar flare.
The new observations suggest that the process may not always begin with one dramatic event.
Instead, a series of smaller releases could progressively alter the magnetic environment until the region reaches a critical state and produces a major eruption.
This provides scientists with a possible physical explanation for the early warning signals they observed.
Why predicting solar flares matters on Earth
A solar flare may occur roughly 150 million kilometres away, but its effects can reach Earth.
Strong solar activity can produce radio blackouts and disturb communication and navigation systems.
Solar eruptions can also send huge clouds of magnetised plasma known as coronal mass ejections (CMEs) towards Earth. When these interact with Earth’s magnetic field, they can produce geomagnetic storms.
Severe space-weather events have the potential to disrupt satellites, power infrastructure, GPS systems and communications.
They can also increase radiation exposure for astronauts and spacecraft.
This is why scientists around the world are working to improve space-weather forecasting.
From an observation to a possible warning system
The researchers are cautious about what the discovery means.
The small brightenings are a promising precursor, but scientists still need to establish how consistently they occur before major flares and whether they can reliably distinguish a flare-producing region from one that remains stable.
In other words, the discovery does not yet mean that scientists can predict every solar flare with certainty.
However, identifying a repeatable pattern that occurs hours before major eruptions could become an important component of future forecasting systems.
Further observations and larger datasets will be needed to determine how reliable the signal is.
India’s solar mission is opening new doors
The study also highlights the growing scientific value of Aditya-L1.
Launched by ISRO in September 2023, the spacecraft was designed to study the Sun and its influence on the space environment around Earth.
Its position at L1 allows scientists to observe solar activity continuously without the interruptions that occur when Earth-based instruments are affected by atmospheric conditions or the Earth’s rotation.
The latest findings demonstrate how observations from different instruments can be combined to understand the chain of events leading to a solar flare.
The research is also an example of Indian scientists contributing to one of space science’s most important practical challenges: protecting modern technology from unpredictable solar activity.
The warning may be hidden in the smallest flashes
The most intriguing part of the discovery is that the Sun’s warning may not arrive as a dramatic signal.
It may begin with a collection of tiny flashes that last only briefly.
If scientists can learn to recognise the pattern reliably, these small events could eventually give space-weather forecasters valuable additional time to assess the possibility of a major flare.
That could help operators prepare satellites, communication networks and other sensitive systems for potentially disruptive solar activity.
The researchers say the findings move scientists a step closer to reliable solar-flare forecasting, although more work is needed before such observations can become an operational prediction tool.
A small clue could lead to a bigger breakthrough
The Sun remains one of the most closely studied objects in the universe, yet many aspects of its explosive behaviour are still not fully understood.
This new research adds an important piece to that puzzle.
The discovery of repeated small energy releases before major flares suggests that the build-up to a powerful solar eruption may leave detectable fingerprints.
For scientists, the next challenge is to determine just how dependable those fingerprints are.
If future observations confirm the pattern, the Sun may no longer be quite as unpredictable as it seems — and tiny flashes could become an important early warning of a much bigger storm.