Stratospheric observatory Sunrise-III reveals intricate solar magnetic structures

A team of researchers, including those from the National Astronomical Observatory of Japan, have discovered unexpectedly complex magnetic structures above quiet regions of the sun using the balloon-borne solar observatory Sunrise-III during its 2024 flight. Their findings, published in The Astrophysical Journal Letters, reveal thin, elongated, thread-like magnetic structures embedded within the magnetic canopy above these quiet regions.

The magnetic canopy forms in the solar atmosphere as magnetic fields concentrated at the sun's surface arc outward with increasing altitude, creating an arch of magnetic structures. However, this canopy is not a uniform structure, but rather contains many thin, elongated magnetic substructures. A numerical simulation of the observed structures suggests they are associated with magnetic field lines twisted by motions at the sun's surface.

Sunrise-III, which maps magnetic fields above the sun's surface, observed how the magnetic field distribution varies with height above the solar limb, particularly in regions without activity like sunspots. These observations, made possible by the observatory's high-precision measurements from the stratosphere, provide crucial insights into how energy is transported from the sun's surface to heat the solar atmosphere.