Indian Solar Mission's New Findings Shed Light on Sun's Mysterious Corona
Scientists in India have made new discoveries about the Sun's corona, a region that remains millions of degrees hotter than the Sun's surface despite frequent energy losses.
The Sun's corona, its outer atmosphere, has long been a mystery to scientists. It remains millions of degrees hotter than the Sun's surface, despite frequent energy losses through solar flares and coronal mass ejections (CMEs).
Astrophysicists in India have made new findings that provide clues to unlocking these mysteries. The discoveries were made using data from the Aditya-L1 solar observation mission in space. The findings were published in the Astrophysical Journal Letters.
The temperature variations in different regions of the Sun defy the laws of physics. The core of the Sun is 15 million degrees Celsius, while the surface is about 5,500 degrees Celsius. The corona, on the other hand, is about 2 million degrees Celsius, and can sometimes reach up to 40 million degrees Celsius.
The corona is where extreme weather events, such as solar flares and CMEs, originate. These events release large amounts of energy into space, causing geomagnetic storms that can affect life on Earth. During normal or low-activity times, the Sun launches two to three CMEs a day. However, during the maximum solar activity cycle, which occurs every 11 years, there can be 10 or more CMEs in a single day.
The scientists behind the study believe that the corona is able to maintain its high temperature due to a mechanism that replenishes the lost energy. They propose two factors that contribute to this mechanism: the bubbling boiling motions on the Sun's surface that generate waves, and the tangled magnetic field lines in the Sun's atmosphere that constantly snap and reconnect.
The study found that the magnetic field lines snapping and reconnecting supply most of the energy to the corona. The waves generated by the bubbling motions on the Sun's surface supply only 7% of the energy requirement, while the magnetic field lines supply the remaining 93%.
The scientists studied a very energetic CME that took place on 5 August 2024. Emissions were recorded by Aditya-L1's coronagraph called Velc (Visible Emission Line Coronagraph). They found that in 10 hours after the CME, the tangled field lines were able to go back to their original place, they reconnected and corona's energy was reconfigured.
These data provide an important benchmark for future studies into the potential energy generation mechanisms in the Sun's atmosphere. The scientists believe that their findings will help answer fundamental questions of physics that defy logic.
| **Energy Source** | **Contribution to Corona's Energy** | | --- | --- | | Waves generated by bubbling motions | 7% | | Magnetic field lines snapping and reconnecting | 93% |
The study's findings have significant implications for our understanding of the Sun's behavior and its impact on life on Earth. Further research is needed to confirm these results and to better understand the mechanisms that govern the Sun's corona.
