《礼记·月令》
仲夏五月，太阳运行的位置在东井；黄昏时，亢星位于南夭的正中；拂晓时，危星位于南天的正中。
仲夏之月，日在东井，昏亢中，旦危中。
In the fifth month of the mid-summer, the location of the sun's path is at Dongjing; at dusk, the Kang star is located in the middle of the southern sky; at dawn, the Wei star is located in the middle of the southern sky.