On August 12, 2026, a total solar eclipse will cross Greenland, Iceland, and Spain before the Moon's shadow leaves Earth near the Balearic Islands at sunset. For observers in Italy, however, the event will be only a partial eclipse, and its visibility will depend heavily on local terrain. Scientists at the Italian National Institute for Astrophysics (INAF) have now produced detailed maps that show exactly which parts of the country will have a clear view of the partially eclipsed Sun.
The challenge for Italian skywatchers is that the eclipse occurs very low in the western sky, just before sunset. At such a low altitude, even modest hills or mountains along the northwestern horizon can completely block the view. To address this, the researchers used a digital elevation model of Italy called Tinitaly, developed by the National Institute of Geophysics and Volcanology (INGV). This model provides terrain data at a resolution of 10 meters per pixel, allowing precise calculation of the horizon in the direction of the Sun.
The team performed ray-tracing calculations that accounted for Earth's curvature and atmospheric refraction, which near the horizon can lift the apparent position of the Sun by about half a degree — roughly the Sun's own diameter. For each point on the map, the researchers computed the angle of the real horizon toward the Sun (azimuth about 288–290 degrees, west-northwest) and sampled the digital elevation model up to 120 kilometers away. Points were then classified into four categories: free view (the partially eclipsed Sun is visible), marginal (within 0.3 degrees of being blocked), blocked by mountains, or Sun already set.
The maps cover three fixed times — 7:30 p.m., 7:50 p.m., and 8:20 p.m. local time — as well as the moment of first contact and the maximum observable eclipse at each location. The percentage of the Sun's disk obscured increases steadily from southeast to northwest. In Calabria, at the southern tip of the mainland, only about 18 percent of the Sun will be covered, while in Piedmont and Liguria in the northwest, the coverage reaches over 93 percent. Unfortunately, in central and southern regions, the absolute maximum of the eclipse occurs after local sunset, making that peak unobservable.
To generate national-scale maps, the researchers used a lower-resolution version of the Tinitaly model resampled to 300 meters per pixel, while for detailed maps of individual 50×50 kilometer tiles they maintained the full 10-meter resolution. The calculations were performed with Python, accounting for the topocentric positions of the Sun and Moon at each point and each instant. The curvature of Earth lowers the apparent height of a distant ridge by nearly 300 meters at 60 kilometers — a significant effect when the Sun is grazing the horizon.
The resulting maps show that observers in western Liguria and Piedmont have the best chance of seeing a deep partial eclipse, with more than 90 percent of the Sun covered. In the rest of northern Italy and much of Tuscany, coverage remains above 70 percent, but the Sun sits very low, so a clear western horizon is essential. The researchers recommend that viewers scout their observation site a few days earlier to confirm that the Sun is visible at sunset.
This eclipse serves as a preview for an even more spectacular total solar eclipse in 2027, which will feature a totality lasting nearly six and a half minutes — among the longest of the century. For now, the detailed maps give Italian astronomy enthusiasts a practical tool to plan their observations and make the most of the August 2026 event.
