Dawn - Yoake

Around the time of dawn. Since the Kansei calendar (implemented in 1798), dawn was defined as the time when the sun reached 7 degrees 21 minutes 40 seconds below the horizon at dawn. It is when the bright stars are no longer visible, and corresponds to the common twilight in Europe. Before the Kansei calendar, dawn was defined as 2.5 hours before sunrise (equivalent to 36 minutes today). In the Edo period, under the seasonal time system, daytime was defined as the time from dawn to dusk, and nighttime was defined as the time from dusk to dawn, and each day and night was divided into six equal parts, with dawn being called ake-rokutsu and dusk being called kure-rokutsu.

[Toshio Watanabe]

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

夜が明けるころ。寛政(かんせい)暦（1798年施行）から、太陽が明け方、地平線下七度21分40秒に達したときを夜明けとした。明るい星が見えなくなるころで、ヨーロッパの常用薄明に相当する。寛政暦以前では日の出前二刻半（現在の36分に相当）をもって夜明けとした。江戸時代、不定時法では夜明けから日暮れまでを昼間、日暮れから夜明けまでを夜間とし、昼夜おのおのを六等分して夜明けを明(あけ)六つ、日暮れを暮(くれ)六つと称した。

［渡辺敏夫］

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