Spring Equinox 2027: the first day of spring

What the spring equinox is

Twice a year the Sun crosses the celestial equator, the projection of Earth's equator onto the sky. The March equinox is the crossing from south to north, the moment the Sun's ecliptic longitude reaches 0 degrees. For an instant the Earth's axis is tipped neither towards nor away from the Sun, the Sun stands directly over the equator at noon, and day and night are close to equal all over the planet. In the Northern Hemisphere it marks the start of astronomical spring; in the Southern Hemisphere, the start of autumn.

In 2027 the moment is 20 Mar, 20:24 UTC, which is 4:24 PM EDT on Saturday, March 20, 2027 where you are. "Equinox" comes from the Latin aequinoctium, "equal night". The other name, vernal equinox, comes from ver, spring.

March 19, 20 or 21?

The equinox is a single instant, so its date depends on your time zone and drifts through the leap-year cycle. In this century it lands on March 20 in UTC in nearly every year, and in the Americas it sometimes arrives on the evening of March 19, as it will in 2028, 2032. The table at the bottom of the page shows the next five years in your time zone.

Day and night are not exactly equal

The name promises 12 hours of day and 12 of night, but your clock disagrees. On the equinox in New York you get 12h 08m of daylight. Two things add the extra minutes. First, sunrise and sunset are timed when the top edge of the Sun's disc touches the horizon, not its centre, which adds a minute or so at each end. Second, the atmosphere bends sunlight over the horizon, so we see the Sun about half a degree higher than it really is, adding a couple of minutes more.

The day when daylight is closest to exactly 12 hours is called the equilux. In the Northern Hemisphere it comes a few days before the March equinox. In New York it is Wednesday, March 17 (12h 00m); in London it is Thursday, March 18. The closer you are to the equator the further the equilux moves from the equinox, and near the equator itself there is none at all, because the day never gets down to 12 hours.

The days lengthen fastest now

Around the equinox day length changes faster than at any other time of year. In New York the days are growing by about 2.7 minutes a day; in London, farther north, by about 4.0 minutes. Compare that with a few seconds a day around the solstices. By the summer solstice in June the gain slows to nothing.

The Sun rises due east everywhere

On the equinox the Sun rises almost exactly due east and sets almost exactly due west from every place on Earth except the poles. In the Sun path chart above, the equinox arc starts and ends at E and W, halfway between the low December arc and the high June arc. At noon the Sun's height above the horizon equals 90 degrees minus your latitude: 49.2° in New York. At the North Pole the Sun rises on about this day for six months of daylight, while at the South Pole it sets for six months of night.

Where the Sun is among the stars

The equinox point is called the First Point of Aries, a name from Greek astronomy 2,000 years ago. Earth's axis slowly wobbles like a spinning top (precession), so the equinox point drifts west along the zodiac by about one degree every 72 years. Today it sits in the constellation Pisces, which is where the Sun is at the equinox, and in about 600 years it will reach Aquarius: the "Age of Aquarius" of the old song. Tropical astrology still counts the equinox as 0 degrees Aries; that is a convention of the tradition, not where the stars are.

Spring equinox traditions

Nowruz, the Iranian New Year

Nowruz ("new day") is the New Year of the Iranian solar calendar, and it begins at the exact moment of the March equinox, the tahvil. In 2027 that is March 20 at 11:54 PM Tehran time. It has been celebrated for at least 3,000 years and is kept by about 300 million people across Iran, Afghanistan, Central Asia, the Caucasus, Kurdish communities and the diaspora. Families set a haft-sin table with seven items whose names start with the letter "s", such as sprouted wheat (sabzeh), apples (sib) and garlic (sir). Before it comes Chaharshanbe Suri, when people jump over bonfires, and it ends on the thirteenth day with Sizdah Bedar, a day of picnics outdoors. Nowruz is on UNESCO's intangible heritage list, and the United Nations recognises March 21 as the International Day of Nowruz.

The serpent of Chichen Itza

At Chichen Itza in Mexico's Yucatan, the stepped pyramid of El Castillo, the Temple of Kukulcan, puts on a show around the equinoxes. In the late afternoon the corners of the pyramid's terraces cast a row of triangles of light and shadow on the side of the northern staircase, which joins up with the carved serpent head at its foot, so a feathered serpent seems to slither down the pyramid. The effect is visible for several days around each equinox, and thousands of visitors gather to watch it. Archaeoastronomers still debate whether the Maya builders designed it on purpose; the pyramid's alignment to the Sun at other dates is better established.

Higan in Japan

In Japan the spring equinox, Shunbun no Hi, is a national holiday; in 2027 it is on Sunday, March 21. The date is announced each February by the National Astronomical Observatory of Japan, based on the calculated equinox. It sits in the middle of Higan, a seven-day Buddhist period when families visit and clean their ancestors' graves and eat botamochi, sweet rice balls covered in red bean paste. Higan, "the other shore", refers to the far shore of enlightenment, and the equinox, with the Sun setting due west, was linked to the Western Pure Land.

Easter, Passover and the equinox

The date of Easter is tied to the spring equinox and the Moon. The rule set by the early church, associated with the Council of Nicaea in 325, puts Easter on the Sunday after the first full moon on or after the equinox. The church fixes the equinox at March 21 and uses tables for the full moon rather than the real sky, so Easter can differ from the astronomical rule. In 2027 the first real full moon after the equinox is on March 22, and Western Easter falls on Sunday, March 28; Orthodox churches, which still use the Julian calendar for the calculation, keep Easter on Sunday, May 2. Passover begins on the 15th of Nisan, at the full moon of the Hebrew spring month, which is why it is usually close to Easter. Our moon calendar lists every full moon.

Ostara and other spring festivals

Modern Pagans celebrate the spring equinox as Ostara, one of the eight festivals of the Wheel of the Year. The name comes from Eostre, a goddess the monk Bede said gave her name to the Anglo-Saxon month around April; how much more was known about her is debated. In Mexico, crowds climb the Pyramid of the Sun at Teotihuacan on the equinox to "recharge" in the spring sunshine, a modern custom.

Southern Hemisphere: the autumn equinox

The March equinox is the same moment worldwide, but south of the equator it is the autumn equinox: in Sydney, Melbourne and Auckland the days are getting shorter from here, and the southern equilux comes a few days after the equinox. The southern spring equinox is the September equinox, next on Thursday, September 23, 2027 (UTC). Set your city above and this page recalculates for you.

Astronomical vs meteorological spring

Astronomical spring runs from the March equinox to the June solstice, about 92.7 days. Meteorological spring is simply March, April and May, which forecasters prefer because whole months make tidy statistics. In the US the equinox is usually called the first day of spring; in the UK and Ireland both are used. Compare all the seasons on the seasons page, or read about the shortest day on the winter solstice page.