Scientists Map Sun's Hidden Side Using Sound Waves

Scientists just figured out how to see around the sun using sound, and it could give us more time to prepare for solar storms that disrupt satellites and power grids.

Researchers at the National Solar Observatory found a way to map magnetic fields on the side of the sun we can't see from Earth. By studying tiny shifts in sound waves moving through the star, they can now detect not just where active regions are forming, but how their magnetic fields are oriented.

This matters because the sun's hidden hemisphere can host powerful active regions that later rotate into view and trigger solar flares. These eruptions can knock out satellites, mess with GPS navigation, and even damage power infrastructure on Earth.

For years, scientists have used a technique called helioseismology to spot large active regions on the far side days before they come into view. But until now, they couldn't determine magnetic polarity, which tells them whether a region might produce dangerous eruptions.

"The sun is constantly ringing with sound waves," explains Dr. Amr Hamada, who led the research published in Scientific Reports. His team discovered that these waves carry more information than anyone realized, including clues about how magnetic fields are structured.

The breakthrough came from detecting incredibly subtle shifts in wave signals. These tiny changes reveal whether magnetic fields point outward or inward, which directly influences how powerful an eruption might become.

The work relies on the Global Oscillation Network Group, a worldwide network of robotic telescopes that continuously records the sun's surface vibrations. Dr. Alexei Pevtsov notes that these oscillations have been tracking far-side activity for years, but the team found hidden details in data scientists were already collecting.

Why This Inspires

Since the sun rotates every 27 days, active regions can become threats to Earth before we get a direct look at their magnetic properties. This new technique essentially gives us X-ray vision around a corner we couldn't peek around before.

Adding far-side magnetic data to existing space weather models could improve early warning systems. Scientists would have more time to assess potential impacts and alert satellite operators, airlines, and power companies about incoming storms.

The research shows how listening more carefully to signals we already receive can reveal entirely new dimensions of understanding. Sometimes the breakthrough isn't gathering new data but hearing what the old data was quietly telling us all along.