40 Fun Facts About Spring Equinox

A 1945 Life magazine story from China fed the US myth that which food stands on end only at the spring equinox?

An egg will balance on its end on any day of the year, given a steady hand. The equinox legend spread across America after reports of a standing craze in wartime Chongqing.

At which ancient Mexican city does a shadow serpent seem to crawl down a pyramid at the spring equinox?

Chichen Itza draws thousands each March to watch triangles of late-afternoon light ripple down El Castillo's balustrade. The effect lasts for weeks, so nobody knows whether the builders planned it.

Which Christian festival falls on the first Sunday after the first full moon on or after the spring equinox?

Easter can fall anywhere from 22 March to 25 April because it follows the Moon as well as the Sun. For the sum, churches treat 21 March as the equinox whatever the sky says.

Which Persian New Year festival, celebrated for over 3,000 years, is timed to the spring equinox?

Nowruz means 'New Day' in Persian. The Iranian calendar year opens that day if the equinox arrives before noon in Tehran, and on the next day if it comes later.

Which country makes the spring equinox a national holiday, spent visiting family graves and holding reunions?

Japan made Vernal Equinox Day a public holiday in 1948. The date is only confirmed in February of the year before, once astronomers have measured when the equinox will fall.

The word equinox comes from Latin aequinoctium, a compound of two words that together mean what?

Equal night is the literal meaning, though the match is not exact. On the equinox itself, daylight lasts a few minutes longer than darkness almost everywhere on the planet.

Which planet's equinox did NASA's Cassini probe study in 2009, on a mission extension named after the event?

Saturn's rings turn edge-on to the Sun at its equinox and dim sharply. In 2009 a hidden moonlet was found by the long shadow it cast across them.

Which live creature often joins the mirror and candles on the haft-sin table Iranians set at the spring equinox?

A goldfish in a bowl is a favourite extra on the table. The seven main items are chosen because their Persian names all begin with the same letter.

Which observance, better known for its 22 April date, did John McConnell propose for the spring equinox of 1970?

Earth Day was first proclaimed by San Francisco's mayor on 21 March 1970. The April version, a nationwide teach-in planned by Senator Gaylord Nelson, followed a month later.

Along which imaginary line does the noon Sun pass directly overhead on the day of the spring equinox?

The Equator is the only place the Sun stands exactly overhead at an equinox. From then until September the overhead point stays in the Northern Hemisphere.

In Australia and the rest of the Southern Hemisphere, the March equinox marks the astronomical start of which season?

Autumn begins in the south at the very moment spring begins in the north. That mismatch is why the hemisphere-neutral name March equinox is often preferred to vernal equinox.

On the day of the spring equinox, the Sun rises from which compass direction almost everywhere on the globe?

Due east at dawn and due west at dusk: early sky-watchers in the tropics spotted that pattern long before anyone noticed the matching hours of light and dark.

At which spot does the Sun rise at the March equinox and then stay above the horizon for about six months?

The North Pole gets just one sunrise and one sunset a year, both at the equinoxes. In between, the Sun circles the sky without setting until late September.

In Western astrology, which zodiac sign does the Sun enter at the March equinox, making it first in the zodiac year?

Aries, the ram, opens the zodiac because astrologers count their twelve signs from the Sun's position at the equinox. The same day begins the first month of Iran's solar calendar.

Which Jewish festival begins on the 15th of Nisan, usually at the first full moon after the spring equinox?

Passover has to fall in spring, so the Hebrew calendar slips in a whole extra month in seven years out of every nineteen to stop its lunar dates drifting toward winter.

Which feature of our planet, tilted about 23.4 degrees, leans neither toward nor away from the Sun at an equinox?

Its rotation axis sits side-on to the Sun at an equinox, so both hemispheres are lit equally. Three months later the same tilt hands one hemisphere its longest day.

Which sky spectacle becomes more likely around the equinoxes, when geomagnetic storms strike most often?

The aurora is sparked by geomagnetic storms, and records going back to the 1850s show that such storms run higher near both equinoxes than in midsummer or midwinter.

In which country do children drown a straw doll called Marzanna to chase winter away on the first day of spring?

Poland's schoolchildren often make the doll themselves and may burn it before the drowning. Superstition says nobody may touch her in the water or look back on the walk home.

Which pope cut ten days from October 1582 to pull the drifting spring equinox back to around 21 March?

Gregory XIII also dropped three leap years from every four centuries. The old Julian calendar ran slightly long, which had let the equinox creep about ten days early.

The Persian New Year at the spring equinox has its roots in the faith of Ahura Mazda, founded by which prophet?

Zoroaster's followers rank the equinox new year among their seven most important festivals. Most of the people who celebrate it treat it as a secular holiday instead.

On the eve of the last Wednesday of the Iranian year, days before the spring equinox, revellers leap over what?

Bonfires blaze in streets, yards and on rooftops for the festival called Chaharshanbe Suri. Jumpers ask the flames to take their winter pallor and hand back a healthy red glow.

The musical Hair made famous the astrological age set by the spring equinox point entering which constellation?

Aquarius is the next stop for the equinox point, which slips through one zodiac constellation roughly every 2,150 years. On modern star-map borders it crosses over around the year 2600.

Which Greek astronomer found that the equinoxes slowly drift against the stars, a motion called precession?

Hipparchus spotted the drift by comparing his own star positions with older records. He put it at no less than one degree a century; the real rate is about one degree every 72 years.

Which 1980s coinage names the date, days before the spring equinox, when daylight and darkness truly match?

Equilux comes early in mid-latitudes. Sunrise and sunset are timed from the Sun's top edge, which shows while its centre is below the horizon, so daylight on the equinox itself runs long.

Which optical effect of the air lifts the Sun into view while it is below the horizon, stretching equinox daylight?

Refraction at the horizon is slightly greater than the Sun's own width. When the bottom of the disc seems to touch the horizon, the whole Sun has in fact already set.

Which art is celebrated worldwide on the March equinox in an annual day that began in Sweden in the early 1990s?

Storytelling got its world day after a Swedish event called All Storytellers Day spread across Scandinavia in 2002. Tellers around the globe agree a shared theme for each year.

Which name, borrowed from a Germanic goddess, did Wiccan writer Aidan Kelly give the spring equinox festival in 1974?

Ostara was Jacob Grimm's 1835 reconstruction of a lost German goddess. Kelly borrowed it for the festival and named the September equinox Mabon at the same time.

Which Southeast Asian temple, built for Suryavarman II, lines its central tower up with the equinox sunrise?

Angkor Wat faces west, unlike most Khmer temples, so crowds on its entrance causeway watch the equinox Sun climb directly over the central spire.

On the thirteenth day after the spring equinox new year, Iranian families traditionally head outdoors for what?

A picnic in the countryside closes the new year holidays on Sizdah Be-dar, which Iran also calls Nature Day. Tradition links it to a rain god's victory over a demon of drought.

Which people celebrate the spring equinox as the day a blacksmith named Kawa led a revolt against the tyrant Zahak?

The Kurds tell of a king with serpents growing from his shoulders, whose thousand-year reign stopped spring from coming until the uprising toppled him.

Followers of which religion end a nineteen-day fast as their new year begins on the spring equinox?

Bahá'ís fast from sunrise to sunset through a month they call Loftiness, which leads straight into the new year. Their founder fixed that day to the equinox itself.

Which name do astronomers give the line between daylight and darkness, which runs from pole to pole at an equinox?

The terminator is also nicknamed the twilight zone. Near the poles around an equinox it creeps along so slowly that a person on foot could out-walk it.

Around each equinox the Sun slips directly behind which spacecraft, briefly swamping the signals they beam down?

Geostationary satellites suffer these 'Sun outages' for a short spell each day, because the Sun's microwave glare drowns their beam. They also dip through the planet's shadow and run on batteries.

On which Mediterranean island does the equinox sunrise shine through the main doorway of the Mnajdra temple complex?

Malta's megalithic temples date from around the fourth millennium BC. At Mnajdra the equinox beam passes the doorway and lights the building's central line from end to end.

In which country does the equinox sunrise light up carved stones deep inside Cairn T at Loughcrew?

Ireland's Loughcrew alignment was only noticed in 1980, when researcher Martin Brennan saw the dawn beam travel down the passage onto the decorated backstone.

The Romans held the Hilaria, rejoicing around the March equinox, for which goddess tied to the shepherd Attis?

Cybele was honoured on 25 March, which the Romans counted as the first day of the year with more daylight than darkness. The festival's name comes from a Greek word for cheerful.

At which ancient Mississippian city did a great circle of timber posts, nicknamed Woodhenge, mark the equinox sunrise?

Cahokia's timber circle stood west of the huge Monks Mound, and archaeologists read it as a solar calendar for timing crops and ceremonies. Public sunrise watches are held there each equinox.

In Egypt and most Arab countries, which family celebration is held on 21 March, the first day of spring?

Mother's Day reached Egypt in 1956. President Nasser ridiculed the idea at first and then accepted it, and neighbouring countries went on to copy the date.

English Heritage lets visitors walk among the stones of which roped-off monument at dawn on equinoxes and solstices?

Stonehenge was off limits on such days for almost fifteen years, under an exclusion zone that lasted until just before the twenty-first century.

In Greek myth, whose yearly return from the underworld to the harvest goddess Demeter brings the spring?

Persephone's return each spring was a symbol of immortality in the Eleusinian Mysteries, which is why she was so often carved on sarcophagi.