vernal equinox

音標(biāo)發(fā)音

The vernal equinox, however, occurs when the center of the sun crosses the Equator.
當(dāng)太陽(yáng)中心橫過(guò)赤道之時(shí)，便是春分。
It issued the Easter Rule which states that Easter shall be celebrated on the first Sunday that occurs after the first full moon on or after the vernal equinox.
這個(gè)理事會(huì)制定了復(fù)活節(jié)的標(biāo)準(zhǔn)：復(fù)活節(jié)應(yīng)該在第一個(gè)滿月后或是春分后的第一個(gè)星期進(jìn)行慶祝。
Therefore, on the vernal equinox day, the daylight hours are actually longer than the length of time between when the sun crosses the horizon at dawn and when the sun crosses the horizon at sunset.
于是，在春分之日，太陽(yáng)從黎明經(jīng)過(guò)地平線生氣之時(shí)，到黃昏經(jīng)過(guò)地平線落下之時(shí)，兩者間的時(shí)長(zhǎng)確實(shí)沒(méi)有我們所看見(jiàn)的白天長(zhǎng)。

Well, obviously Florida and California are two states where one can ride 12 months a year but for motorcyclists in less temperate climes it can be hard hanging up your helmet until the vernal equinox.
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the time in the spring when the sun crosses the equator, and when night and day are of equal length

the time at which the sun crosses the plane of the equator towards the relevant hemisphere, making day and night of equal length. It occurs about March 21 in the N hemisphere (Sept 23 in the S hemisphere)