Light, not lava, is the real showrunner at Yosemite’s so‑called firefall, where Horsetail Fall can blaze orange as if a spell had been cast on the cliff. On a few evenings each late winter, the Sun’s low angle aligns almost perfectly with the narrow chute of falling water, so that direct rays graze the granite wall and strike the cascade from behind.The spectacle looks supernatural because the con...More