Sep232026 · UTC
September Equinox
Astronomical autumn begins in the Northern Hemisphere and spring in the Southern Hemisphere.
Your guide to the sky
Equinoxes & Solstices.
The turning points of Earth’s year. Mark the equinoxes and solstices, with one global instant and a different seasonal story in each hemisphere.
Plan ahead
Upcoming equinoxes & solstices
The next 400 days in the available catalog. Event pages explain local visibility and prediction uncertainty.
Dec212026 · UTC
December Solstice
Astronomical winter begins in the Northern Hemisphere and summer in the Southern Hemisphere.
Mar202027 · UTC
March Equinox
Astronomical spring begins in the Northern Hemisphere and autumn in the Southern Hemisphere.
Jun212027 · UTC
June Solstice
Astronomical summer begins in the Northern Hemisphere and winter in the Southern Hemisphere.
Sep232027 · UTC
September Equinox
Astronomical autumn begins in the Northern Hemisphere and spring in the Southern Hemisphere.
Catalog refreshed . Dates and predictions come from the catalog used by Forecast Bar, with a source on every event.
Calendar day groupings use UTC. Event times adapt to your device’s time zone when JavaScript is available. Exact local visibility and weather can differ from the global catalog timing.
A little context. A better view.
Equinoxes & Solstices: a field guide
Astronomical seasons have precise boundaries
Equinoxes and solstices are calculated from the Earth–Sun geometry. Their exact times are global; the local calendar date can differ by time zone.
The hemispheres tell opposite stories
A June solstice marks the start of astronomical summer in the Northern Hemisphere and winter in the Southern Hemisphere. Event details identify both hemispheres.
These are calendar milestones
An equinox or solstice is not a brief object appearing in the sky. No special equipment or clear weather is required to mark the instant in your calendar.
Weather seasons are a different convention
Astronomical season boundaries do not predict a particular temperature or a sudden weather change. Local climate and seasonal weather follow their own patterns.
Learn more: U.S. Naval Observatory astronomical data
Take the sky with you
From a date on a calendar
to a night worth remembering.
Open the astronomy calendar in Forecast Bar to explore events alongside your local weather and astronomy alert settings.
