Scientists reveal the most detailed images of the Sun’s surface ever taken

Tengrinews.kz — Scientists have obtained the most detailed images of the Sun’s surface to date. The images reveal structures just around 20 kilometres across and, for the first time, show small plasma vortices, according to the journal Nature.
The images were captured using the four-metre Daniel K. Inouye Solar Telescope in Hawaii, the world’s largest solar telescope. Researchers observed an active region near a sunspot.
The images have a resolution of about 19 kilometres. For comparison, the Sun’s diameter is roughly 1.4 million kilometres. This level of detail revealed the star’s surface to be far more complex and dynamic than previous images had shown.
The magnetic field and plasma movement on the Sun's surface. Source: nature.com
Researchers were particularly interested in numerous small vortices along the boundaries of regions with strong magnetic fields. Some were only about 25 kilometres across. In total, scientists analysed 47 such vortices in detail, ranging in size from 25 to 170 kilometres.
The structures turned out to be manifestations of what is known as the Kelvin–Helmholtz instability. This phenomenon occurs when adjacent flows of liquid or gas move at different speeds. Similar vortices can be seen on Earth, for example in the atmosphere and oceans. Scientists had long suspected that such processes could occur on the Sun, but until now they had not been directly observed in the photosphere, the star’s visible surface.

The main obstacle had been insufficient resolution, as the structures are too small for most existing solar telescopes to detect. The new observations have, for the first time, shown the boundaries of magnetic regions not as relatively smooth lines, but as areas filled with constantly forming vortices and streaks.
To verify the nature of the structures, scientists compared the observations with computer simulations of the solar atmosphere. The models reproduced similar vortices, supporting the researchers’ conclusion that they were caused by Kelvin–Helmholtz instability.
The discovery is significant not only because of the record-breaking detail of the images. Such vortices may play a role in transporting matter, energy and magnetic fields across the Sun. Researchers believe that studying them could help improve our understanding of the processes taking place in the star’s magnetically active regions.