What is an Equinox? | National Geographic

What are equinoxes? What causes these astronomical events? Find out how they influence the seasons and hours of daylight on each planet. ➡ Subscribe: About National Geographic: National Geographic is the world’s premium destination for science, exploration, and adventure. Through their world-class scientists, photographers, journalists, and filmmakers, Nat Geo gets you closer to the stories that matter and past the edge of what’s possible. Get More National Geographic: Offici