Indian-led team makes breakthrough in understanding solar superheating phenomenon
NASA scientists have made significant progress in explaining one of the long-standing mysteries surrounding our Sun. Led by an Indian researcher, a team of scientists have identified magnetic interactions as the likely cause behind superheating a moss-like structure in the Sun’s atmosphere to over a hundred times hotter than its surroundings.
Similar to algal moss found growing near bodies of water on Earth, the Sun also exhibits mossy patchy structures in its atmosphere composed of plasma. Known as ‘solar moss’, these formations blossom around sunspots under strong magnetic conditions. Recent observations revealed that temperatures within the moss region can spike to an astounding 5.5 million degrees Celsius, far exceeding the near 100,000 degree layer just below.
To unravel this conundrum, a NASA team analyzed observations from the Interface Region Imaging Spectrograph (IRIS) satellite and Hi-C rocket mission. Combining the imagery with simulations, researchers noticed that the moss area hosts a complex web of interwoven magnetic field lines. Their chaotic interactions were generating electric currents capable of imparting immense heat.
Led by Dr. Souvik Bose, the team’s simulations demonstrated how magnetic tangling near the moss fuelled these currents through Joule heating. With sunspots harboring the Sun’s strongest magnetism, minor variances in field potency across regions could account for the moss’s super-hot temperatures. The findings, published in Nature Astronomy, bring scientists a step closer to decrypting how the outer solar atmosphere achieves its fusion-like temperatures.
Upcoming Hi-C flybys will allow expanding this work. By continuing to dissect magnetic dances on the Sun, we deepen understanding of phenomena influencing space weather with implications for life on Earth.
