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Equinox

September Equinox 2027

Date & Time

UTC

Overview

Sun crosses the celestial equator heading south — autumn begins in the Northern Hemisphere.

Data Source

Solstice and equinox dates calculated from JPL DE440 ephemeris (the same planetary/lunar ephemeris used by NASA). Meteor shower peak dates and ZHR values follow the International Meteor Organization (IMO) annual calendar. Planetary event data from NASA Horizons system.

Plan Your Observation

Use these free tools to prepare for the event:

☀️ Solar & Golden Hour Calculator🌆 Twilight Calculator🌙 MoonSync — Moon Phase & Interference🔭 Telescope FOV Calculator
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