Circular Sun Halo
Sun halos, like the one photographed near Rome, are formed by ice crystals in high clouds creating a 22-degree ring. Visible more often than rainbows, they can be seen by blocking the Sun with a fingertip. Today's partial solar eclipse offers a rarer "ring of fire" to those along the Moon's shadow path.
HD image at https://apod.nasa.gov/apod/ap231014.html
