“Xīn Nián Kuài Lè!” 新年快乐!
Tuesday marks the Lunar New Year in many countries around the world, including China, Korea and Vietnam.
Unlike the western Gregorian calendar, a lunisolar calendar uses the 29.53-day cycle of the Moon’s phases to define the months of the year – usually starting each month when the new Moon phase occurs, or on the day when the young crescent Moon is first glimpsed after sunset. The placement of those months is anchored to a solstice or equinox. Since solstices and equinoxes are Earth-Sun phenomena, and completely independent of the Moon’s phases, lunisolar calendars drift compared to our Gregorian system. And, because the Moon runs through its cycle 12.37 times per year, every second or third lunisolar year requires an extra 13th intercalary or “leap” month to stay in line with the solar calendar.
The Chinese lunisolar calendar places the December solstice into the eleventh month, causing the first month of the subsequent year to begin about two months later on the new Moon that occurs somewhere between January 21 and February 20 on the Gregorian calendar. Most of the time, that Moon phase lands in early February.
When the Moon officially reaches its new Moon phase on Tuesday at 12:46 a.m. EST (or 05:46 Greenwich Mean Time), it will trigger the Lunar New Year observed in many Asian countries. Since that new Moon happens on Tuesday, Beijing-time, too, that will be the first day of Chinese New Year holiday celebrations worldwide. It is also the first day of the Spring Festival 春节, or Chūn Jié (“CHWUN-jee-EH”), which ends with the Lantern Festival on the full Moon two weeks later. Families often kick things off early by celebrating New Year’s Eve Monday night with a meal together.
In Vietnam, the new year is called Tết, short for tết nguyên đán, meaning “Festival of the First Morning of the First Day.” Koreans celebrate Seolla, from Eumnyeok Seollal “lunar new year.” Japan switched to the western Gregorian new year in 1873.
Happy Year of the Tiger! The Chinese use a zodiac system – but this version doesn’t relate to the Sun’s journey along the ecliptic or even to any of the animal constellations. Instead, the Chinese zodiac preserves the sense of that word from the Ancient Greek expression zōdiakòs kýklos (ζῳδιακός κύκλος), “cycle of small animals.” An animal and its attributes are assigned to each year in a repeating 12-year cycle.

The order of the animals is said to have been determined by a great race to become the guards of the Jade Emperor — with their rank determined by the order in which the animals arrived at the finish line at the palace gates. The race involved both running and swimming. The mighty ox was a shoe-in to win the race. But the rat woke up early on race-day and took the lead. Arriving at the river, he feared to cross it. When the ox arrived, the rat jumped onto the gentle ox’s back and hitched a ride across. Upon reaching the opposite shore, the little rascal jumped off of the tired ox and raced ahead to win the race, leaving the ox with second place! Did he cheat – or was he clever, and worthy to be senior-most of the guards?
2022 is the third year of the current cycle, named for the third-place finisher, the tiger.
Nisg̱a’a tradition
The Nisg̱a’a, an Indigenous population in British Columbia, traditionally celebrate their new year when the crescent Moon first appears after its new phase in February or March. This celebration is called Hobiyee, a name derived from the expression “Hobixis Hee,” which means “the Moon is in the shape of the hoobix,” the bowl of the Nisg̱a’a traditional wooden spoon. The young Moon’s orientation after sunset, with its horn-tips pointing upwards, resembles a celestial scoop; if seen, the year is thought to be filled with an abundance of salmon, river saak (candlefish), berries and more.
The first month of the Nisga’a year is called Buxw-laḵs, where buxw means “to blow about” and laḵs means “needles” — a sure sign of winter’s end.
Chris Vaughan is a science writer, geophysicist, astronomer, planetary scientist and an “outreach RASCal.” He writes Astronomy Skylights, and you can follow him on Twitter at @astrogeoguy. He can also bring his Digital Starlab portable inflatable planetarium to your school or other daytime or evening event. Contact him through AstroGeo.ca to tour the Universe together.