Revisiting Mount Wilson: How corrected solar data revealed a groundbreaking discovery

Between 1982 and 2012, the 150-foot solar tower at Mount Wilson Observatory collected a vast archive of observations of the Sun’s surface. In a series of recent studies, Professor Roger Ulrich, together with colleagues Dr. Tham Tran and Dr. John Boyden at UCLA, have revisited these data, running a thorough recalibration of the findings. Their results led them to a crucial discovery: two properties of the Sun’s plasma which were once thought to be separate are actually two faces of the same underlying effect, which plays a fundamental role in shaping the Sun’s magnetic field throughout the solar cycle.