The Sun's surface has unveiled a new secret: ultra fine magnetic "curtains" that create striking patterns of bright and dark stripes across the solar photosphere. Thanks to groundbreaking observations from the NSF Daniel K. Inouye Solar Telescope in Hawaii, scientists have captured the sharpest ever images of these previously unseen structures, revealing magnetic field variations at scales as small as 20 kilometres.
Daniel K. Inouye Solar Telescope on the left hand side of the Haleakala Observatory (Credit : Ekrem Canli)
These striations, observed against the walls of solar convection cells called granules, result from sheets of magnetic fields that ripple and shift like fabric blowing in the wind. As sunlight passes through these magnetic "curtains," the interaction creates alternating patterns of brightness and darkness that directly trace the underlying magnetic field variations. When the magnetic field is weaker within a curtain compared to its surroundings, it appears dark; when relatively stronger, it appears bright.
The discovery by the team led by NSO scientist Dr. David Kuridze, represents a significant leap forward in solar astronomy. They used the Inouye's Visible Broadband Imager operating in the G-band, achieving an impressive spatial resolution better than 0.03 arc seconds on the Sun's visible surface. This clarity allowed researchers to observe magnetic fluctuations of only a hundred gauss, comparable to a typical refrigerator magnet's strength.
The Sun's visible surface (Credit : ESA)
What makes this discovery particularly exciting is how it bridges observation with theory. The team compared their high resolution images with cutting edge simulations that recreate the physics of the Sun's surface, allowing them to clearly link these observed stripes to those predicted in state of the art models. This connection helps scientists better understand the fundamental nature of these magnetic structures.
These striations are the fingerprints of fine-scale magnetic field variations - Dr. David Kuridze, the study's lead author from the National Solar Observatory.
The magnetic variations alter plasma density and opacity, creating tiny shifts in the visible surface called Wilson depressions, detectable only through the Inouye telescope's unique 4-meter primary mirror the world's largest solar telescope.
Understanding these magnetic structures extends far beyond academic curiosity. Studying the magnetic architecture of the solar surface is essential for understanding the most energetic events in the Sun's outer atmosphere such as flares, eruptions, and coronal mass ejections and consequently improving space weather predictions. As our society becomes increasingly dependent on technology, accurate space weather forecasting becomes crucial for protecting satellites, power grids, and communication systems.
The research also has broader astrophysical implications. Similar magnetically induced stripes have been observed in more distant astrophysical objects, such as molecular clouds. The Inouye telescope's high resolution, combined with advanced simulations, provides a unique window into understanding magnetic field behaviour across various cosmic environments. This groundbreaking study, published in The Astrophysical Journal Letters, represents just the beginning of what the Inouye Solar Telescope can reveal about our nearest star's complex magnetic personality.
