每年6月22日前后太阳到达黄经90°时为夏至。今年夏至为6月21日。《月令七十二候集解》:“五月中……夏,假也,至,极也,万物于此皆假大而至极也。”夏至是二十四节气中最早被确定的一个节气。公元前七世纪,先人采用土圭测日影,夏至这一天日影最短,因此把这一天称作“夏至”。 Around June 22 each year, the sun reaches the summer solstice when it reaches 90 °. This summer solstice is June 21. “The month of the month seventy-two waiting for solution”: “mid-May ... summer, fake too, to, very, everything in this fake great and extremely. ” The summer solstice is twenty-four solar terms was first identified A solar term. The seventh century BC, the ancestors used Tuyou to measure the shadow of Japan, the shortest shadow on the day of the Summer Solstice, so this day is called “the summer solstice.”