haustjafndægur

Haustjafndægur refers to the autumnal equinox in Icelandic. An equinox occurs twice a year, around March 20 or 21 and September 22 or 23, when the plane of Earth's equator passes through the center of the Sun's disk. At this time, day and night are of approximately equal length across the globe. Haustjafndægur marks the astronomical beginning of autumn in the Northern Hemisphere. Following haustjafndægur, the days begin to shorten and the nights lengthen as the Northern Hemisphere tilts further away from the sun. The term itself is a compound of "haust" meaning autumn and "jafndægur" meaning equinox, literally translating to "autumn equinox." Culturally, haustjafndægur has historically been a significant marker of seasonal change, often associated with harvest festivals and a transition into a period of shorter daylight hours. The precise date can vary slightly each year due to the Earth's orbit and the Gregorian calendar.