<Tr> <Th> 2020 </Th> <Td> 20 </Td> <Td> 03: 50 </Td> <Td> 20 </Td> <Td> 21: 44 </Td> <Td> 22 </Td> <Td> 13: 31 </Td> <Td> 21 </Td> <Td> 10: 02 </Td> </Tr> <P> An equinox is the moment in which the plane of Earth's equator passes through the center of the Sun's disk, which occurs twice each year, around 20 March and 23 September . </P> <P> On an equinox, day and night are of approximately equal duration all over the planet . They are not exactly equal, however, due to the angular size of the sun and atmospheric refraction . To avoid this ambiguity, the word equilux is sometimes (but rarely) used to mean a day in which the durations of light and darkness are equal . See Length of equinoctial day and night for further discussion . </P> <P> The word is derived from the Latin aequinoctium, aequus (equal) and nox (genitive noctis) (night). </P>

When is the day as long as the night