Solar corona to display active-phase features during August 12, 2026 total eclipse

The total solar eclipse on Aug. 12, 2026 will pass over Greenland, Iceland, Spain and the Balearic Islands, providing a brief view of the Sun’s outer atmosphere, the corona. Because the eclipse falls about two years after the peak of Solar Cycle 25, scientists expect the corona to show an intermediate level of activity—more structured than the quiet-sun eclipses of 2017, 2019 and 2020, but less intricate than the corona observed during the solar-maximum eclipse of April 2024.

Solar physicist Ryan French of the Laboratory for Atmospheric and Space Physics explained that the Sun follows an 11-year magnetic cycle, with sunspot numbers peaking at solar maximum and declining thereafter. "We’re a third of the way past the peak in terms of amplitude and years passed," French said, adding that the monthly sunspot number for August 2026 is projected around 102, compared with about 144 in 2024.

The corona’s shape is dictated by magnetic fields anchored to sunspot regions. During the declining phase, observers can anticipate prominent streamers extending several solar diameters from the eclipsed disk, with possible asymmetry between the two sides of the Sun. The relatively short totality—about 2 minutes 18 seconds—may also allow multiple smaller prominences to be seen around the Moon’s edge, as the Moon will only slightly exceed the Sun’s apparent size.

While a coronal mass ejection (CME) could be captured if one occurs near the eclipse date, French noted that CMEs move slowly and would appear as a static feature rather than a moving eruption during the brief totality. Forecasts from Predictive Science and real-time coronagraph images from instruments such as NASA’s SOHO LASCO and the COSMO K-Coronagraph will help observers anticipate the corona’s appearance, though the exact configuration will only be known on the day of the eclipse.