Ask the Chatbot Games & Quizzes History & Society Science & Tech Biographies Animals & Nature Geography & Travel Arts & Culture ProCon Money Videos
Equinox
Introduction References & Edit History Related Topics
Images & Videos
Diagram showing Earth's elliptical orbit around the Sun with labeled points for aphelion, perihelion, solstices, and equinoxes, and distances from the Sun at aphelion and perihelion.
A large tree with leaves turning orange in fall.
A diagram of the celestial sphere with Earth at the center, showing the celestial equator, ecliptic, and labeled positions of the vernal and autumnal equinoxes, as well as the north celestial and ecliptic poles. sunlight strikes parts of Earth differently Diagram showing Earth's orbit around the Sun with labeled positions for the summer solstice, winter solstice, vernal equinox, and autumnal equinox, illustrating how Earth's tilt causes the seasons.
What is the summer solstice?
Quizzes
View of the Andromeda Galaxy (Messier 31, M31).
Astronomy and Space Quiz
The orbits of the planets and other elements of the solar system, including asteroids, Kuiper belt, Oort cloud, comet
Space Odyssey
Nicolaus Copernicus. Nicolas Copernicus (1473-1543) Polish astronomer. In 1543 he published, forward proof of a Heliocentric (sun centered) universe. Coloured stipple engraving published London 1802. De revolutionibus orbium coelestium libri vi.
All About Astronomy
Encyclopaedia Britannica thistle graphic to be used with a Mendel/Consumer quiz in place of a photograph.
36 Questions from Britannica’s Most Popular Science Quizzes

Equinox: References & Edit History

Article Contributors

Primary Contributors

  • The Editors of Encyclopaedia Britannica
    Encyclopaedia Britannica's editors oversee subject areas in which they have extensive knowledge, whether from years of experience gained by working on that content or via study for an advanced degree. They write new content and verify and edit content received from contributors.

Other Encyclopedia Britannica Contributors

Article History

Type Description Contributor Date
Article title updated for style. Nov 10, 2026
Corrected typographical error. Apr 30, 2026
Article revised and updated. Mar 19, 2026
Modified link of Web site: CORE - Equinox transition at the magnetic equator in Africa: analysis of ESF ionograms (PDF). Feb 18, 2026
Add new Web site: CORE - Equinox transition at the magnetic equator in Africa: analysis of ESF ionograms (PDF). Nov 19, 2025
Add new Web site: CORE - Equinox transition at the magnetic equator in Africa: analysis of ESF ionograms (PDF). Oct 11, 2025
Add new Web site: Academia - Which Equinox? Aug 23, 2024
Add new Web site: Ancient Origins - How Ancient People Marked the Equinox Around the World. May 31, 2024
Media added. Aug 15, 2023
Add new Web site: Space.com - What is an Equinox? Sep 24, 2021
Corrected display issue. Aug 15, 2019
Add new Web site: John A. Dutton e-Education Institute - Understanding the Equinox and the Solstice. Jan 09, 2019
Add new Web site: National Geographic - Equinox. Aug 16, 2018
Add new Web site: NASA - Visible Earth - Equinoxes and Solstices from Space. May 28, 2018
Add new Web site: Royal Museums Greenwich - When is the summer solstice? Apr 03, 2017
Add new Web site: Fact Monster - Science - Equinox. Dec 21, 2011
Add new Web site: Wolfram Research - Equinox. Dec 20, 2011
Add new Web site: How Stuff Works - Science - Equinox. Dec 20, 2011
Article added to new online database. Jul 20, 1998
View Changes:
Article History
Revised:
By: