Scientists have used the world’s largest telescope to study the sun to capture the highest-resolution pictures yet of the sun’s surface, revealing small, violent plasma whirlpools moving across it.
The discovery could change how scientists understand the way energy and magnetic fields move through the sun’s atmosphere. These whirlpools seem like an efficient way to move energy and magnetic flux, and could also be responsible for braiding the sun’s magnetic fields at small scales.
Such braided fields are thought to store and release the energy that powers solar flares and other eruptions — and may help explain why the sun’s outer atmosphere is so unexpectedly hot.
The team’s findings were published in Nature on August 5.
Details on the edge
The part of the sun that we see is called the photosphere. This is a chaotic environment filled with a roiling mass of superheated plasma. The light we see on the earth is energy emitted by this plasma.
Astronomers have been taking pictures of the sun’s exterior for a long time, and they have always seen a beehive-like structure there. The cells in this structure are called convection cells. Each cell spans up to around 2,000 km — the distance from Mumbai to Guwahati — and lasts for 5-10 minutes before dissipating. The visible features of a convection cell are called granules. All these granules together form the outer visible layer of the sun.
In all the pictures taken of the sun’s surface in the past century, the edges of these granules were blurred. They looked like frayed cotton.
And for decades, solar physicists have wondered if these edges are really frayed or if they will find more detail if they observe them using a more powerful telescope. The new images have settled the debate.
“The weakness is in the telescope’s aperture,” the researchers — from the U.S. National Science Foundation National Solar Observatory (NSO), Germany’s Max Planck Institute for Solar System Research (MPS), and the High Altitude Observatory (HAO) — wrote in their paper in Nature.
It seems that with telescopes whose primary mirrors are smaller than 2 m wide, it is not possible for physicists to observe the fundamental perturbations on the sun’s surface.
Cleaning up the blur
For their study, the researchers turned to the NSF Daniel K. Inouye Solar Telescope (DKIST) in Hawaii. Perched near the 10,000-foot-high summit of the Haleakalā volcano, the DKIST features a giant 4-m primary mirror. It started scientific operations in late 2019.
The team used it to observe a magnetically active region on the sun called NOAA 14060, capturing light at a wavelength of 416 nanometres (which is visible light of a blue-violet colour). They also paired the telescope with a high-speed FastCam camera developed jointly by NSO and MPS. The camera had a stunning exposure time of 100 microseconds, capturing up to 740 frames per second.
With the help of this camera, the researchers took many pictures of the sun’s turbulent atmosphere. Not all of the pictures were clear.
Then, one member of the research team, Michiel van Noort of MPS, used an advanced image processing technology called multi-frame blind deconvolution to remove the blurring that occurs when the sun is photographed from the earth. Then the team combined multiple cleaned-up images to recover a clear image.
Dr. Noort used this technology to capture images of the sun’s surface of dimension 5,800 km x 4,350 km at a resolution of 19 km. This is like being able to spot a 10-rupee coin in Mumbai from Pune.
Thus, the team found that the edges of the solar granules are not smooth at all. Instead, there are innumerable small coils of plasma, each only 25-170 km long, separated by around 65 km. And they had their own little magnetic fields.
Wind over a river
The researchers also found that these small plasma coils were not stationary. They moved along the boundaries of the granules, twisting and interacting with one another. And as they did, they generated whirlpools in the plasma — vortices that spun rapidly and changed shape within seconds.
When a strong wind blows over a calm river, small whirlpools form on the water. Generally, physicists say, a vortex is formed at the interface where two adjacent fluids move past each other at different speeds. The same thing has been found happening on the sun.
Scientists have previously found such whirlpools in the atmosphere of gaseous planets like Jupiter. This is the first time scientists have seen such a wave moving on the surface of the sun.
These whirlpools in the sun’s plasma also rapidly grow in size. Using high-speed cameras, the scientists found that the fastest-growing vortices became 2.7-times larger than their original size in just 18 seconds. Even those that grew a little slower took only 71 seconds to reach this size. They rotated at about 1.6-2.8 km/s.
The scientists found that, over three minutes, these whirlpools constantly form, merge with each other, and break up again.
A new way
The team confirmed its observations with the DKIST using magneto-hydrodynamics simulations on a computer. In both cases, the vortices’ rotational speed and energy were the same. In other words, these whirlpools are essentially the sun’s engines: they capture the sun’s internal magnetic energy and radiate it out into the universe.
The simulations also suggested the whirlpools lie 100-400 km below the photosphere.
The findings give solar physicists a new way to investigate the boundary between convection and magnetism. The whirlpools generate turbulence and continuously distort the magnetic fields. In doing so, they could provide the small-scale motion needed to braid magnetic field lines and release magnetic energy higher in the atmosphere.
The next step is to determine how much energy these instabilities transport and how the small vortices are connected to the more energetic events of the sun’s atmosphere.
Shamim Haque Mondal is with the Physics Division, State Forensic Science Laboratory, Kolkata.
Published – September 07, 2026 09:00 am IST
