Astronomers using the world’s most powerful solar telescope have captured the highest-resolution images yet of the sun’s visible surface, revealing swirling, vortex-like patterns of superheated plasma that provide new insights into solar dynamics. The observations, made with the U.S. National Science Foundation’s Daniel K. Inouye Solar Telescope in Hawaii, mark the first unambiguous detection of Kelvin-Helmholtz instability (KHI) on a star’s surface, a phenomenon previously observed only in Earth’s oceans, planetary atmospheres, and simulations.
The findings, published in Nature, show plasma flows moving at different speeds along the sun’s photosphere—a thin outer layer roughly 60 miles (100 km) deep—creating the distinctive spiral patterns. These vortices, ranging from 12 to 100 miles (19 to 170 km) in diameter, could help researchers understand the mechanisms behind violent solar weather, including coronal mass ejections (CMEs) and solar flares, which threaten satellite operations, GPS navigation, power grids, and global communications on Earth.
Key observations and implications
The images were initially captured to test and calibrate the telescope’s capabilities, but researchers soon realized they had obtained an unprecedented view of the sun’s dynamic surface. The swirling patterns, described as resembling Vincent van Gogh’s The Starry Night, are driven by magnetized plasma interacting at varying velocities, a process known as KHI.
"The interface can become unstable and develop wave-like vortices that grow in size until they break apart," explained Friedrich Wöger, a senior scientist at the National Solar Observatory. This instability has been observed in fluids on Earth and other planets, but this is the first time it has been detected at such fine scales on the solar surface.
Researchers combined the telescope’s observations with highly specialized computer simulations to confirm the presence of KHI. The study’s co-authors emphasized that these findings could improve predictions of solar storms, which pose significant risks to modern infrastructure.
Technical breakthroughs and scientific significance
The Daniel K. Inouye Solar Telescope, with its 4-meter primary mirror and state-of-the-art adaptive optics, enabled the detection of these ultrafine details. Prior to this, astronomers lacked the tools to observe such small-scale phenomena on the sun.
"For decades, seeing these vortices at such tiny scales remained elusive," said Jacqueline Keane, NSF Program Director for the National Solar Observatory. "By pairing a massive four-meter mirror with cutting-edge optics and instruments, the telescope delivers the resolving power needed to reveal these details for the first time."
The discovery also highlights the role of magnetic fields in shaping solar plasma flows. Unlike Earth-based KHI, which is driven by temperature or density differences, the sun’s version is influenced by magnetic forces, adding complexity to the phenomenon.
Broader impact on solar research
Scientists believe these observations could revolutionize our understanding of solar weather and its potential impacts on Earth. Solar flares and CMEs release massive bursts of energy that, when directed toward Earth, can disrupt critical systems. Improved detection of KHI and related processes may enhance early warning systems for solar storms, allowing for better preparation and mitigation.
"We’ve never observed the Sun at that resolution," said Michael Wheatland, an astrophysicist at the University of Sydney not involved in the study. "In this amazing detail, we see all of this really interesting fundamental physics happening."
The research team plans to continue studying the sun’s surface to uncover additional small-scale magnetic and plasma interactions, further refining models of solar activity.