On the afternoon of May 7, a rare superior mirage appeared on the sea of Penglai near east China's Shandong Province. Thousan ds of residents and tourists had the luck to view the wonderful scene. According to meteorologists, superior mirage, which reflects landscapes nearby, is one of the three natural wonders on the sea of Penglai, the other two being mirage that reflects landscapes from afar and advection fog that is formed when dense fog on the sea is raised by light wind and floats horizontally in the mid-air.