The Sun Has Hidden Whirlpools: Scientists Just Filmed Them In Action For The First Time

For the first time, scientists have directly observed swirling, wave-like instabilities forming on the Sun’s visible surface near magnetic flux concentrations in an active region. The discovery could help explain what powers the Sun’s most explosive outbursts, the same solar storms capable of knocking out power grids, GPS, and satellites here on Earth.

Using the world’s largest solar telescope, a team of researchers captured clear evidence of these structures forming in real time. Scientists had long predicted they should exist, but had never been able to see them directly. Now they have, and the findings are published in the journal Nature.

At the edges of magnetic flux concentrations, the Sun is generating swirling vortices only a few dozen kilometers across, with measured sizes ranging from roughly 25 to 170 kilometers. The images reveal a solar surface more complex and dynamic than previous observations could resolve, and capturing that detail required a telescope with resolving power earlier instruments probably lacked.

A Telescope Powerful Enough to See It

Capturing this required the NSF’s Daniel K. Inouye Solar Telescope, known as DKIST, located in Hawaii. It is the world’s first 4-meter-class solar telescope, giving it the resolving power to distinguish features on the Sun as small as about 19 kilometers, near the theoretical diffraction limit of DKIST at this wavelength and in this dataset.

Earlier solar telescopes, those with smaller mirrors, probably lacked the resolving power to detect structures this small. The paper notes the phenomenon has likely gone unobserved because “the characteristic spatial scale is not easily accessible by telescopes with aperture sizes below 2 m,” even though physicists had predicted their existence for years.

A Familiar Physics Phenomenon, Now Seen on the Sun

This phenomenon, called a Kelvin-Helmholtz instability, is named after two 19th-century physicists, Lord Kelvin and Hermann von Helmholtz, who first described how fluids moving at different speeds generate turbulent, rolling structures along their shared boundary. The same process has been observed in Earth’s oceans, in the atmospheres of Jupiter and Saturn, and at the edge of Earth’s own magnetic field where solar wind pushes against it.

On the Sun, powerful bundles of magnetic field poke up through the surface and create concentrated magnetic regions. Around the edges of these regions, hot plasma flows rapidly in one direction while the material just inside the magnetic boundary moves at a very different speed. That mismatch in speed is precisely the recipe for one of these instabilities to form.

Researchers identified 47 of these vortex structures in the observational data, spaced about 65 kilometers apart on average.

Computer simulations of a patch of the Sun’s surface helped confirm what the telescope captured, checked against 94 separate instability occurrences. The vortex spacing in the simulations closely matched what the telescope observed, and so did the speeds.

“The consistency between the numerical simulations and observations demonstrates that the numerical model sufficiently captures the physical processes leading to the KHI,” the authors write.

The Swirls Could Explain the Sun’s Most Violent Outbursts

Solar physicists have a leading theory for how the Sun builds up the energy behind flares, jets, and coronal mass ejections, the eruptions that drive space weather and can disrupt power grids and satellites on Earth. It is called flux braiding. Magnetic field lines twist around each other the way strands of hair twist into a braid, building up tension until the lines snap, cross, and reconnect in new shapes. That sudden rearrangement releases a burst of energy.

What scientists have not been able to pin down is what starts the twisting in the first place. This new discovery may be part of the answer. Because the swirls appear to be happening constantly, everywhere the Sun’s magnetic field is strong enough, they could work as the everyday engine that keeps the braiding going.

That same mixing could help crack two more longstanding puzzles. One is why the Sun’s outer atmosphere runs far hotter than its surface. “Kelvin-Helmholtz instability is likely a mechanism that contributes to the heating of the outer atmosphere and is part of the solution of the longstanding enigma of why stars have a million degrees Kelvin hot corona,” said Dr. Thomas Rimmele, chief technologist at the National Solar Observatory. The other is how the Sun’s magnetic field manages to flip roughly every 11 years, a fast pace by cosmic standards that existing models have struggled to explain.

Simulations further reveal that deeper below the surface, these instabilities are fragmenting monolithic magnetic elements into several smaller structures, offering a new window into how the Sun organizes its magnetic field in layers humans cannot directly observe.

Decades of theoretical work said these swirling instabilities should be present throughout the solar photosphere near magnetic boundaries, constantly shredding and reforming them. DKIST has now confirmed that prediction, giving solar physicists a new tool for understanding how the Sun actually works.

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