AUTUMN ARRIVES WITH THE SEPTEMBER EQUINOX 2025
NEW DELHI, Sept. 22 — The turning of the seasons takes place today with the arrival of the September equinox, when day and night balance almost equally across the planet. At precisely 18:19 UTC (11:49 p.m. IST, 2:19 p.m. EDT, 19:20 BST), the Sun will be positioned directly above Earth’s equator, bringing a moment of near symmetry in light and darkness worldwide.
For the Northern Hemisphere, this marks the end of astronomical summer and the official beginning of autumn. In the Southern Hemisphere, the same instant ushers in the start of spring.
The word equinox comes from the Latin aequus (equal) and nox (night), evoking the ancient recognition of this balance of light. On this day, the Sun rises due east and sets due west across the globe, a phenomenon that underscores the geometric precision of Earth’s orbit and axial tilt.
Scientists note that while the equinox suggests equal day and night, the equality is not exact. Atmospheric refraction and the Sun’s apparent size cause daylight to last slightly longer, making the perfect balance occur a few days earlier or later — a moment known as the equilux.
Cultural and Historical Resonance
For millennia, equinoxes have held deep cultural and agricultural meaning. They marked the harvest season in ancient civilizations and continue to be celebrated today:
Japan observes Shūbun no Hi (Autumnal Equinox Day), a national holiday centered on family gatherings, temple visits, and seasonal foods like botamochi.
Ancient monuments such as Chichén Itzá in Mexico and Angkor Wat in Cambodia were designed with equinox alignments, turning the play of sunlight into ritual spectacle.
Across Europe and Asia, harvest festivals coincide with the equinox, echoing the rhythm of farming cycles.
Astronomical Context
The September equinox is one of two yearly events when the Earth’s tilt is neutral relative to the Sun. Unlike the solstices, when the poles lean toward or away from the Sun, the equinox brings equal illumination to both hemispheres.
Date: Monday, 22 September 2025
Exact Moment: ~18:19 UTC
Northern Hemisphere: Start of autumn
Southern Hemisphere: Start of spring
Day vs Night: Nearly equal duration worldwide
A Universal Turning Point
From farmers timing their harvests to astronomers calibrating celestial maps, the equinox has long provided a universal marker in human history. Today, it remains a moment to pause and reflect on the natural cycles that connect all corners of the Earth.
As the Sun crosses the celestial equator this evening, skies worldwide will mirror an ancient truth: that balance, however brief, is woven into the fabric of our planet’s journey around the Sun.
