The traditional Chinese calendar divides a year into 24 solar terms (节气/節氣).
[1] Shuāngjiàng, Sōkō, Sanggang, or Sương giáng (Chinese and Japanese: 霜降; pinyin: shuāngjiàng; rōmaji: sōkō; Korean: 상강; romaja: sanggang; Vietnamese: sương giáng; lit.
It more often refers in particular to the day when the Sun is exactly at the celestial longitude of 210°.
In the Gregorian calendar, it usually begins around October 23 and ends around November 7.
The western holiday of Halloween occurs in this solar term.