Environment Planet Earth 7 Enlightening Facts About the Vernal Equinox From dancing tree fairies to spring fever, there’s more to the March equinox than equal night and day. By Melissa Breyer Editorial Director Hunter College F.I.T., State University of New York Cornell University Melissa Breyer is Treehugger’s editorial director. She is a sustainability expert and author whose work has been published by the New York Times and National Geographic, among others. our editorial process Melissa Breyer Updated March 17, 2021 Fact checked by Haley Mast Fact checker Harvard University Extension School Haley Mast is a writer, fact checker, and conservationist with a certification in sustainability. Our Fact-Checking Process Article fact-checked on Mar 18, 2021 Haley Mast kazumi miyaoto / Getty Images Share Twitter Pinterest Email Environment Weather Outdoors Conservation There is really no secret as to why the change from winter to spring has been celebrated throughout time. Even for those with the luxury of things like insulated homes and off-season food, winter can be hard and spring is beautiful. It’s a magical time, and both the body and spirit rejoice with the increase in sunlight and a wakening world. For 2021, the equinox falls on Saturday, March 20 at 5:37 a.m. EDT. That the March equinox signals the first day of spring – for those in the northern hemisphere; and the first day of winter for those in the south – is a well-known fact. Lesser known are some of the more curious occurrences that the day and impending season have to offer. Consider the following. 1. You Say Equinox, I Say Equilux While “equinox” comes from the Latin for equal night, you probably have heard that day and night are not exactly equal on the equinox. Why? The sun may be crossing the celestial equator, but sunlight can be a fickle thing. Because the sun is a disk and not a point, and because of atmospheric refraction, those of us at mid-temperate latitudes actually get a few extra minutes of daylight on the equinox. For the exact split, we have the unsung hero called the equilux, from the Latin for equal light, which comes a few days before its much-more famous sibling, the equinox. 2. Spring Fever is Deployed You may know the symptoms; a flushed face, increased heart rate, daydreaming and an inclination towards romance – all wrapped up in a very strong desire to ditch the drudgery and go outside and frolic. The prognosis? Spring fever. And as it turns out, there may be more to it than emotional exuberance that winter is over. There is plenty of anecdotal evidence suggesting a biological basis for the boost of mood, desire, and energy that comes with the vernal equinox. Although the exact causes remain elusive, it’s likely that hormones play a role. 3. Things Get Precise The fall and spring equinoxes are the only two days during the year when the sun rises exactly due east and sets exactly due west. As a way to hone your sense of direction, pick a landmark from a vantage point where you live and note where the sun rises and sets on the equinox – now you’ll always know east and west. 4. The Great Sphinx Gazes Directly into the Sunrise Although of course we’re not supposed to look directly at the sun, on the morning of the equinox the Great Sphinx of Giza does exactly that. There are a number of other ancient sites that play tricks with the equinox as well, like Chichen Itza and Angkor Wat. 5. Easter is Determined The vernal equinox is like a calendar marker to determine what date Easter will fall on. In the year 325, the Council of Nicaea decided that Easter would be held on the first Sunday after the first full moon occurring on or after the vernal equinox. If the full moon falls on Sunday, Easter gets pushed back a week so that it doesn’t coincide with Passover. For 2021, Easter will fall on April 4. 6. The Fairies Come Out to Dance The Anjana of Spanish Cantabrian mythology are 6-inch-tall fairies who take care of the forests. They can communicate with water, help injured animals and storm-damaged trees, and guide those who become lost in the woods. During the night of the vernal equinox, they flock to the fells and dance until dawn, scattering roses all about. Anyone lucky enough to find one of their floral gifts – a rose with purple, green, blue, or golden petals – will have happiness for the rest of their life. 7. Earth Isn’t the Only Planet to Have All the Fun Saturn gets in on the equinox action too. Though it’s a bit harder earned. Saturn also has an equinox every spring and autumn, but since seasons on the ringed planet are a bit more, you know, languid, the wait between equinoxes is notable. Saturn's equinoxes occur around every 15 Earth years; the next one will take place on May 6, 2025. View Article Sources "New York, New York, USA — Sunrise, Sunset, and Daylength, March 2020." timeanddate.com. Nicholson, Christie. "Fact or Fiction?: "Spring Fever" Is a Real Phenomenon." Scientific American, 2007. Bikos, Konstantin. "Calculating the Easter Date." timeanddate.com. "Saturn at equinox." esa, 2019.