Why a Mathematician Is Chasing Eclipses With Algorithms and Cameras

The sun hangs low over the plains of Castile and León, in the north-central region of Spain. But from a slope of the mountain Pico Trigaza, it appears that a few puffy white clouds have started to block the sun. That’s vexing. A group of researchers, some wearing cardboard eclipse glasses, is clustered around sets of portable telescopes and cameras connected to laptops. All this gear is scattered on tabletops perched on the mountainside. On the computer screens, the sun’s disk looks like a deep orange crescent that is slowly waning. That’s because the moon began to crawl across it about half an hour ago. In 25 minutes, it will obscure the sun completely, producing an eerie and wondrous phenomenon—a total solar eclipse.