Aditya-L1 mission findings offer clues to Sun's corona heating mystery

Researchers studying data from India’s first dedicated solar observation mission, Aditya-L1, have reported findings that may explain why the Sun’s outer atmosphere, or corona, is significantly hotter than its surface. While the Sun’s visible surface, the photosphere, is approximately 5,500 degrees Celsius, the corona can reach temperatures between 2 million and 40 million degrees Celsius.

The study, led by Professor R. Ramesh of the Indian Institute of Astrophysics (IIA) and published in the Astrophysical Journal Letters, addresses the mystery of how the corona maintains such extreme heat despite losing vast amounts of energy through frequent solar eruptions. These eruptions, including solar flares and coronal mass ejections (CMEs), release energy and charged particles into space.

Understanding these processes is critical because CMEs can trigger geomagnetic storms on Earth, potentially disrupting power grids, communication networks, navigation systems, and satellites.