Indian New Year Traditions Celebration of Celestial Timekeeping

If there is one force that binds humanity across cultures, it is the shared joy of renewal and rebirth. And what bet­ter symbol of renewal exists than the arrival of spring? In the grand tapestry of the Earth’s seasons, the Vasant (spring) reigns supreme. In Indian culture, the odds are so highly in favour of the popularity of the spring that it has been termed as Rituraj (the king of the seasons). This regal title is no mere poetic flourish; it is deeply root­ed in the rhythms of the cosmos.

In the Indian system of timekeep­ing, a season is known as a ritu, and each ritu spans two months. The an­cient seers of India identified six ritus, each with its own unique character and connection to the natural world: Vasant (spring), Grishma (summer), Varsha (monsoon), Sharad (au­tumn), Hemanta (early winter) and Shishira (late winter). These ritus are not arbitrary divisions but are deeply intertwined with the Earth’s journey around the Sun. As a matter of fact, the seasons themselves are born from the Earth’s delicate tilt of approximately 23.5 degrees relative to the Sun. It is this celestial setting that gifts us the cyclical dance of warmth and cold, growth and dormancy in the form of seasons. But beyond the beauty of blooming flowers and gentle breezes lies a profound as­tronomical truth: the timing of seasons, their onset, duration, and departure, are all governed by the precise movements of celestial bodies.

TIME IS CYCLICAL, NOT LINEAR

In the Indian traditions, time is not linear but cyclical, mirroring the pe­riodic motions of the Sun, the Moon and the stars. Spring, like all seasons, has a beginning, a period of flourishing and an end—yet it carries the eternal promise of return. But what celestial event heralds the arrival of this beloved season? The answer lies in the Vernal Equinox, a moment of cosmic balance that earmarks the ‘rebirth of life’ in the Northern Hemisphere. (Kindly note, here in the context of Vernal Equinox, Spring means Spring of the Northern Hemisphere as the Southern hemisphere seasons are an inversion of the North­ern hemisphere seasons). The Sanskrit text Ritusamhara, attributed to the poet Kalidasa, beautifully encapsulates the essence of these seasons.

Each ritu is a reflection of the Sun’s apparent movement across the sky, divided into the two-month intervals that align with the tropical zodiac. For instance, Vasant begins when the Sun continues its journey through Ar­ies (Mesha). This division is not just a matter of celestial mechanics but also a cultural framework that guides agricul­tural practices, festivals and even daily life. The ritus are a testament to the profound understanding of astronomy of the ancient Indians, and their ability to harmonise human existence with the rhythms of nature.

Image Courtesy: Wikipedia/ By Tau’olunga – Own work, CC BY-SA 2.5

As we delve deeper into the astro­nomical underpinnings of the ritus, we encounter the concept of the equinoxes, those pivotal moments when day and night stand in perfect equilibrium. The word ‘equinox’ itself is derived from the Latin words,‘aequus’ meaning ‘equal’ and ‘nox’ meaning ‘night, a fitting name for a phenomenon that occurs twice a year when the Sun crosses the celestial equator and shines overhead the Equa­tor (see figure above). For the Earth, tilted at its characteristic 23.5 degrees, these moments are marked by the Sun rising due east and setting due west, bathing the planet in equal parts with light and darkness. The Vernal Equi­nox, which occurs around March 20 or 21, signals the beginning of spring in the Northern Hemisphere, while the Autumnal Equinox, around September 22 or 23, heralds the arrival of autumn (See figure below).

CELESTIAL MARKERS OF SEASONS

It can be said that the equinoxes are defi­nitely the celestial markers that define the boundaries of the seasons. Just as the ri­tus are a celebration of nature’s cyclical beauty, the equinoxes are a reminder of the cosmic order that governs our lives. Together, they form the foundation of India’s New Year traditions, which are as much about astronomy as they are about culture. As we explore these traditions further, we will see how the ancient Indi­ans wove the threads of time, astronomy and spirituality into a tapestry that con­tinues to inspire and guide us today.

In the course of the northwards mo­tion of the Sun (known as Uttarayan) the Sun crosses the Celestial Equator (projection of Earth’s Equator onto the sky) which is Declination 0 in terms of Equatorial Coordinate System and moves up, making the days longer and longer in the Northern hemisphere in the time to come. This accompanies a change in weather in the Northern hemi­sphere, making it warmer, blossoming of spring flowers, beginning of a new cycle of plant growth.

Going deep into observational as­tronomy, there is an interesting con­nection of the Vernal Equinox with the constellations of the zodiac (the band of constellations that the Sun appears to pass through as it moves across the sky). Traditionally, the Vernal Equinox marks the beginning of the zodiac sign of Aries, the first sign in the zodiac and hence is also referred to as the ‘First Point of Aries’.

THE PRECESSION PHENOMENA

One of the most fascinating aspects of the Vernal Equinox is its connection to the precession of the Earth’s axis. Pre­cession, which is the third type of mo­tion apart from the Earth’s daily rota­tion and yearly revolution around the Sun (See figure on the following page), is the slow wobble of the Earth’s axis, caused by the gravitational pull of the Sun and the Moon, which completes a full cycle approximately every 25,772 years. This wobble causes the position

of the equinoxes to shift gradually over time. The Vernal Equinox slowly moves backwards through the zodiac, at a rate of approximately one degree every ~72 years of time span, a phenomenon known as the precession of the equi­noxes. In the current era, the Vernal Equinox has been in Pisces zodiac since around 68 BCE and is slated to move to Aquarius around 2600 CE.

The discovery or observation of precession phenomenon is attributed to Greek astronomer Hipparchus in the 2nd century BCE. But it is beyond any doubt that Vedic Hindus were aware of the precession of equinoxes caused by the wobbling of the Earth’s axis. This is evident from the fact that they shifted the zero point of their zodiac from time-to-time. Accordingly, the celestial lists were modified from time-to-time with changes in the Vernal Equinox, for the position of the first nakshatra. Naksha­tra in Indian astronomy are 27 equal spaces into which the zodiac can be divided, each space being 360°/27 = 13°20’ wide over the celestial sphere. There were times when the Vasanta Sampat was in Mrigashirsha (Orion) [B.G. Tilak (1922)]. During the times of Shatapatha Brahmana, it was near Krittikas (Pleiades), during the time of Surya-Prajnapti it was in Bharani (35, 39, and 41 Arietis) and in the Siddhan­tic era, it shifted to Ashvini (ß and Ari­etis). Ancient Indian astronomers Vish­nuchandra and Munjala gave the rate of precession of equinoxes as 56.9” and 59.2” per year respectively. This knowledge underscores the advanced astronomical understanding of ancient Indian scholars.

Image Courtesy: https://cococubed.com/images/astro101/precession_top.svg

Accordingly, two types of practices originated while considering the zodiac, viz., tropical or sayana (used in Western world) and sidereal nirayana (used by Indians). Ayana refers to the precession. Hence, sayana means ‘with ayana’, here the starting point of Aries is determined with reference to the precessed equi­noctial point. Nirayana means ‘with­out ayana’, here that the starting point of Aries is determined without reference to a precessed point, but to the actual observed position of the distant stars. The difference between the tropical and sidereal zodiacs is called ayanamsha. In other words, ayanamsha can be called the difference between the point of Vi­shuva (Vernal Equinox) and that of the ‘First Point of Aries’.

INDIAN CALENDAR SYSTEM: TIMELESS DIALOGUE BETWEEN THE EARTH AND THE SKY

The Indian calendar system is a unique blend of lunar and solar cycles, known as the luni-solar calendar. This system, which has been in use for thousands of years, is based on the movements of both the Moon and the Sun. The lunar month is determined by the Moon’s phases, while the solar year is based on the Earth’s orbit around the Sun. The luni-solar calendar ensures that festivals and New Year celebrations are aligned with both lunar and solar events, mak­ing it a highly accurate and culturally significant system. The Nava Samvat­sar or the New Year in the luni-solar calendar typically begins around the Vernal Equinox. This period marks the Sun’s entry into the Aries zodiac sign, known as Mesha Samkranti. The luni-solar calendar is used in various forms across India, with regional variations in the names and dates of the New Year.

India’s New Year celebrations, root­ed in the sidereal solar cycle, reflect an ancient astronomical precision. Unlike the Gregorian calendar, which follows fixed dates, these festivals align with the Sun’s transition into Aries (Medam/Chithirai) around April 14–15, as cal­culated by the Nirayana system. This

sidereal approach, detailed in texts like the Surya Siddhanta, contrasts with the tropical equinox (March 20–21), em­phasizing India’s unique blend of stellar and solar observations. Termed Mesha Sankramana in Vedic traditions, this celestial shift symbolises renewal and is celebrated diversely across regions.

Around this period of the year, in Kerala, Vishu begins with the Vishuk­kani ritual, reflecting regional customs of auspicious ‘first sights’, while Tamil Nadu’s Puthandu celebrates the Sun’s entry into Chithirai (Aries) with the Kanni tradition. Punjab’s Baisakhi, Bengal’s Pohela Boishakh, Assam’s Bo­hag Bihu coincide with the Rabi har­vest, aligning with the Sun’s transition into Aries. Maharashtra’s Gudi Padwa (marked by hoisting victory flags) and Nepal’s Navavarsha follow regional al­manacs, blending celestial and cultural rhythms. Meanwhile, in Karnataka, Telangana, and Andhra Pradesh, Ugadi (also called as Samvatsaradi) marks the lunar new year, determined by the first day of Chaitra in the lunisolar cal­endar. Though it often falls near the vernal equinox, Ugadi marks the new year, determined by the first day of the lunar month Chaitra. While its date is set by the Moon’s cycle (New Moon), the broader lunisolar calendar ensures it typically falls near the Sun’s movement toward Aries and the vernal equinox (March 20–21), though it is not directly based on the Sun’s position. Even India’s National Calendar, adopted in 1957, aligns with this astronomical legacy, commencing on March 22 (post-vernal equinox) as Chaitra 1. While the Gre­gorian New Year lacks astronomical ties, India’s festivals—whether solar, lunar, or lunisolar—unite in harmonis­ing human life with cosmic rhythms, embodying a timeless dialogue between earth and sky.

For ancient civilizations, the Vernal Equinox was more than an astronomical event—it was a sacred moment where human ingenuity met the cosmos. Mar­vels like England’s Stonehenge, aligned precisely with the equinoxes, or Cam­bodia’s 12th-century Angkor Wat, where the Sun crowns its central tower only on this day, stand as testaments to this celestial reverence. The Mayan Temple of Kukulkan in Chichen Itza (in Mexico) dazzles with equinoctial light-and-shadow serpents, while in Thiru­vananthapuram, the Sun’s golden disk slips perfectly through the windows of the Sree Padmanabhaswamy Temple, uniting stone and sky. These architec­tural wonders reveal how our ancestors wove astronomy into their spiritual and daily lives.

Culturally, the equinox remains a  global celebration. Iran’s Nowruz, the Persian New Year, blooms on the March equinox, symbolizing renewal. In Japan, families honour ancestors during Higan, balancing light and darkness. Ancient Romans celebrated Cybele, the mother goddess, while India’s diverse New Year festivals echo this solar transition. This day marks the beginning of the cycle of the zero shadow days between Tropic of Cancer and Tropic of Capricorn at different latitudes on different dates which attract astronomy enthusiasts all around. From temple alignments to har­vest festivals, humanity’s shared rhythm with the equinox endures—a timeless dance of earth, sky and spirit.

This Gregorian year (in 2025), the Vernal Equinox (March Equinox) moment has fallen on Thursday, 20 March 2025, 14:31 IST (09:31 UTC). Vasant ritu with its visible effects in na­ture, signifies positivity. The onset of Vasant indicated by the Vernal Equi­nox (Vasanta Sampat) definitely makes it the nava prabhat of vasanta ritu (a new dawn of spring)—a time for cel­ebration and moving ahead for making the nation astronomically vibrant and scientifically vigilant. As we celebrate the Vernal Equinox and the Indian New Year, let us remember the ancient wis­dom that connects us to the cosmos. Let us embrace the positivity and renewal that spring brings and move forward with hope and determination. Wishing all a very Happy Indian New Year!

* The writer is an amateur astron­omer and science communicator ac­tive in STEAM education, and is Prin­cipal Investigator, Astro STREAM Project, Saptarshi India (under Global Sky Partners Programme of Las Cum­bres Observatory). He is the National Coordinator, Saptarshi India Asteroid Search Campaign (under IASC).