Scientists Discover How Tiny Clouds Form in the Sun's Outer Layer

By Space.Fan Editorial DeskOctober 3, 2026 at 11:02 AM UTC

Researchers used computer models to reveal how magnetic activity on the Sun creates cool, dense pockets of gas.

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The Drop

The Sun's atmosphere is a very busy place filled with magnetic fields that constantly snap and reconnect. When these magnetic lines break and rejoin, they release a lot of energy. This process can create little bubbles of plasma called plasmoids. Scientists have wondered for a long time how these plasmoids can sometimes become very cold compared to the super-hot environment around them. To find out, a team of researchers built a sophisticated computer simulation to mimic what happens in the Sun's middle layer, known as the chromosphere. They used complex math to track how heat and cooling move through the gas. The model shows that in certain areas where the magnetic pressure is low, the plasma inside these bubbles can get trapped. As more gas gets stuck inside these bubbles, it ts to cool down rapidly. The simulation shows that this cooling happens because the gas becomes so dense that it loses heat much faster than the surrounding area. This creates a chain reaction that turns hot, active plasma into a dense, cooler structure trapped within the magnetic bubble. This process is like a sudden temperature drop in a hot room caused by a fast change in air pressure. The team found that this happens quite effectively in conditions where the magnetic field is strong compared to the plasma pressure. When the conditions are different, the cooling does not get the chance to spiral out of control.

Why It Matters

Understanding these cool, dense structures helps scientists solve a long-standing mystery about the Sun's atmosphere. It shows that magnetic reconnection is not just about making things hotter; it can also create sudden, localized cooling. This helps experts explain why we sometimes see cool matter acting differently than the hot gas around it in solar observations.

The Catch

This discovery comes from a computer model, which is a mathematical representation of the Sun, rather than a direct photo or telescope observation. While the simulation is very detailed, it relies on specific assumptions about how solar gas behaves. Real-world conditions on the Sun are even more complicated, so future telescope observations are needed to confirm if these tiny, cold structures appear exactly as the computer predicted.

Put That in Perspective

Scientists plan to use these findings to better interpret images from high-resolution solar telescopes. By knowing what to look for, they can better understand how energy flows from the Sun's surface into its outer atmosphere.

Source October 3, 2026

Abdullah Zafar, Lei Ni, Samrat Sen, Yuhao Chen, Mohamed Sedik, Mehdi Yousefzadeh, Jun Lin

Yunnan Observatories, Chinese Academy of Sciences; Dr. K. S. Krishnan Geomagnetic Research Laboratory; Peking University·The Astrophysical Journal·10.3847/1538-4357/aea6d5