March Equinox
March 20, 2026
Start of astronomical spring in the Northern Hemisphere / autumn in the Southern Hemisphere. Day and night are nearly equal worldwide.
June Solstice
June 21, 2026
Northern summer / southern winter solstice. Longest day of the year north of the Equator; midnight sun begins near the Arctic Circle.
September Equinox
September 22, 2026
Start of astronomical autumn in the Northern Hemisphere / spring in the Southern Hemisphere. Another near-equal day-and-night checkpoint.
December Solstice
December 21, 2026
Northern winter / southern summer solstice. Shortest day north of the Equator; longest day in the Southern Hemisphere.
Daylight Extremes
Solstice Day Length Comparison
| City | June Solstice sample | December Solstice sample |
|---|---|---|
| New York | 15h 5m 0s | 9h 15m 0s |
| London | 16h 38m 0s | 7h 49m 0s |
| Sydney | 9h 52m 0s | 14h 24m 0s |
| Singapore | 12h 11m 0s | 12h 1m 0s |
Why Seasons Change Sunrise and Sunset
Earth’s axis is tilted about 23.5° relative to its orbit. As we travel around the Sun, that tilt points each hemisphere toward or away from sunlight, stretching or compressing the daily solar arc. Solstices are the tilt extremes; equinoxes are the balance points. The result is the familiar rhythm of earlier/later sunrises — and the dramatic high-latitude swings that produce white nights and polar night.
Planning with Season Markers
- Photographers: summer solstice brings long golden hours at high latitudes; winter solstice packs dramatic low sun angles into short days.
- Travelers: check destination day length months ahead — “summer” in Sydney is December, not June.
- Solar energy: panel yield tracks both day length and solar altitude at noon across the season cycle.
Dig deeper with Day Length, our solstice & equinox guide, and midnight sun & polar night.
Seasons Frequently Asked Questions
Solstices mark the Sun’s maximum northern or southern declination (longest/shortest days). Equinoxes mark when the Sun crosses the celestial equator (nearly equal day and night).
Not exactly for most locations. Refraction and the Sun’s disk make daylight slightly longer than 12 hours on the equinox itself; the “equilux” date can differ by a few days.
The Equation of Time — from Earth’s elliptical orbit and axial tilt — shifts clock-time sunrise so the earliest sunrise usually arrives a few days before the solstice.
They share the same four astronomical instants, but the seasons are opposite: June solstice is northern summer and southern winter.
Open your city page for a 12-month sunrise/sunset overview, or use the Day Length calculator for today’s daylight span.