hohohosJGloHWGlibWtikWBGkawtnag |first2=Hongfeng |title=The Twenty-four Solar Terms of the Chinese Calendar and the Calculation for Them |journal=Purple Mountain Observatory |date=1994 |url=https://en.cnki.com.cn/Article_en/CJFDTotal-GXKK403.013.htm |access-date=9 March 2021 |archive-date=12 June 2021 |archive-url=https://web.archive.org/web/20210612151759/https://en.cnki.com.cn/Article_en/CJFDTotal-GXKK403.013.htm |url-status=dead }}</ref> Dàshǔ (大暑), Taisho, Daeseo, or Đại thử (Chinese and Japanese: 大暑; pinyin: dàshǔ; rōmaji: taisho; Korean: 대서; romaja: daeseo; Vietnamese: đại thử; "major heat") is the 12th solar term. It begins when the Sun reaches the celestial longitude of 120° and ends when it reaches the longitude of 135°. It more often refers in particular to the day when the Sun is exactly at the celestial longitude of 120°. In the Gregorian calendar, it usually begins around 22 July (23 July Chinese lunisolar calendar time) and ends around 7 August.