Fig. 2From: Response of aurora candidates in the Chinese official histories to the space climate during 511–1876Proportions of the aurora candidates in LSA and HSA periods. Overall, white, red, and blue in each solar activity period (bar chart on the left), and those during the whole periods (pie chart on the right). The proportion is computed by aurora year counts divided by the year counts of the period. The proportions of LSA (PLSA) and HSA (PHSA) periods are denotedBack to article page