The traditional Chinese calendar divides a year into 24 solar terms.
[1] Lìqiū, Risshū, Ipchu, or Lập thu (Chinese: 立秋; pinyin: lìqiū) is the 13th solar term.
It begins when the Sun reaches the celestial longitude of 135° and ends when it reaches the longitude of 150°.
It more often refers in particular to the day when the Sun is exactly at the celestial longitude of 135°.
Liqiu signifies the beginning of autumn in East Asian cultures.