# A Mathematician’s Quest to Capture the Sun’s Enigmatic Corona Using advanced algorithms and custom optics, researchers map solar heat during total eclipses. - **Source:** [IEEE Spectrum](https://spectrum.ieee.org/) - **Published:** 2026-11-05 - **Topic:** [science](https://brifing.si/c/science) - **Original article:** - **On Brifing:** https://brifing.si/s/f237dc5e-16e5-4497-a651-d15802b6d3ba ## Chasing Eclipses in Spain On the slopes of Pico Trigaza, Spain, mathematician Miloslav Druckmüller and his team prepared for their 19th solar eclipse expedition. Despite concerns regarding cloud cover, the team deployed specialized telescopes and cameras to capture the sun’s corona. This mission aimed to gather data during the 107 seconds of totality available on August 12. ## The Corona's Thermal Mystery The sun's outer atmosphere, the corona, remains a scientific enigma due to its extreme heat compared to the solar surface. While the surface is 5,500 degrees Celsius, the corona reaches one million degrees. Researchers study this region to understand why temperatures rise further from the core, a phenomenon that defies standard fusion expectations. ## Limitations of Standard Coronagraphs Specialized telescopes called coronagraphs use opaque disks to block the sun's glare, but diffraction often obscures the inner corona. Total solar eclipses provide a unique natural advantage, as the moon acts as a perfect occulter. This allows scientists to observe the corona's structure nearly down to the sun's surface without light diffraction interference. ## Advanced Optical Instrument Design Druckmüller designed a unique instrument incorporating eight astrocameras, each equipped with specific spectral filters. These filters detect emission spectra from iron ions, which are associated with different temperature levels. By analyzing the abundance of these ions, the team gains precise insights into the distribution of heat within the sun's outer atmosphere. ## The Role of Image Processing Capturing the corona is difficult because the contrast between its brightest and darkest parts is one to a million. Druckmüller uses custom algorithms to combine 200 frames with varying exposure times. This process, which takes two days per image, effectively bridges the gap between raw sensor data and human-perceivable visual detail. ## Calibration and Data Integrity To ensure accuracy, the team calibrates data against thousands of reference images, including flat fields and dark frames. Flat fields correct for telescope optics and dust, while dark frames remove sensor-generated artifacts. A single finished composite image requires approximately 3,000 input frames to filter out noise and reveal subtle magnetic field lines. ## Collaboration with Solar Physicists Druckmüller’s partnership with solar physicist Shadia Habbal began after she discovered his high-resolution eclipse images. Their collaboration combines his mathematical expertise in image processing with her scientific focus on solar wind. Together, they reveal tiny, previously unseen features in the corona that provide critical data on solar plasma and magnetic structures. ## Strategic Deployment and Logistics Since 2008, the Solar Wind Sherpas team has deployed to multiple locations to mitigate the risk of bad weather. For the August 12 event, teams were split between Iceland and Spain. Despite Iceland offering a higher sun angle, Spain was chosen as a critical backup site to ensure at least some data collection. ## Fieldwork Under Spartan Conditions The research team, including five doctoral candidates, traveled over 2,000 kilometers from Brno to reach the Spanish mountainside. They utilized an abandoned hut as a base, powering equipment via car batteries and a nearby telecommunication outpost. Living on yoga mats and propane-cooked meals, they maintained focus on the high-stakes scientific objective. ## The Challenge of Low Altitude Observing the eclipse at just 8 degrees above the horizon presented significant atmospheric challenges. Light rays had to pass through a thicker layer of the atmosphere, increasing distortion compared to higher-altitude observations. The team relied on the 1,600-meter elevation of Pico Trigaza to minimize these effects and maximize the quality of their data. ## Comparing Space-Based Observations While NASA’s Solar Dynamics Observatory captures the inner corona in ultraviolet light, it lacks the extended view provided by visible emission lines. The European Proba-3 mission attempts to simulate eclipses using two spacecraft, but ground-based photography remains superior for capturing specific spectral details. This makes eclipse expeditions essential for modern solar physics research. ## Scientific Impact of Totality The 107 seconds of totality provide a rare window into the sun's upper atmosphere that cannot be replicated by current technology. By mapping iron ion dispersal, the team contributes to a deeper understanding of interplanetary space heat patterns. This work transforms fleeting celestial events into permanent, high-fidelity data for long-term solar study. ## Sources covering this story - https://spectrum.ieee.org/2026-solar-eclipse — --- _Summary written by Brifing from the original reporting. Copyright in the original article belongs to its publisher; read the full piece at the link above._