autumnal equinox

基本解释

The Autumnal Equinox is the best time for wheat-sowing.
秋分种麦最相宜。
《新英汉大辞典》
MacRobert said the full moon falling on the autumnal equinox is simply one of many astronomical coincidences that happen to be occurring this month.
麦克罗伯特说满月于秋分日落下不过是众多天文巧合事件中的一例，碰巧发生在了本月。
Even though the sun rises due east and sets due west on the autumnal equinox, "you'll only see an east sun rising and west sun setting with an obstruction-free horizon," Young said.
尽管秋分时太阳从正东方升起到正西方落下，“你只能在毫无遮挡视野开阔的地平线上看到这种现象，”扬说道。

Depending on your definition of the seasons, that means they have either 20 days (Labor Day) or 36 days (the Autumnal Equinox) left.
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If you work the tide changes in Puget Sound, it is your rotten luck that low tide shifts after the autumnal equinox into the nighttime hours.
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Although his heavenly body-inspired market timing may seem far-fetched, Crawford's work (using the Bradley model) correctly called for a steep drop in September 2001 and a low on the autumnal equinox that year.
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the time at which the sun crosses the plane of the equator away from the relevant hemisphere, making day and night of equal length. It occurs about Sept 23 in the N hemisphere (March 21 in the S hemisphere)