What happens when day and night almost match up?

Every year around late March, something interesting happens in the sky. On March 20, 2026, at 10:46 a. m. Eastern Time, the sun will cross a special line in the sky. This event is called the spring equinox. It’s the moment when winter fades and spring arrives in the Northern Hemisphere. Days get longer, temperatures rise, and plants start to wake up. But why does this happen? And why isn’t it the same date every year? The Earth spins on a tilted axis, like a wobbly top. Because of this tilt, different parts of the planet get sunlight at different angles throughout the year. When the Northern Hemisphere leans toward the sun, it’s summer there. When it leans away, it’s winter. The Southern Hemisphere does the opposite. So while people in the north are digging out their spring jackets, those in the south might be heading to the beach.But here’s something odd. The Earth doesn’t take exactly 365 days to go around the sun. It actually takes about six extra hours. That small difference adds up over time. To fix this, we add an extra day every four years. This is why the spring equinox doesn’t always land on the same day. It can happen between March 19 and 21. It’s like a calendar puzzle that never quite fits perfectly. This shifting date might seem confusing. But it’s a reminder that our planet doesn’t move in neat, round numbers. Nature doesn’t follow a strict schedule, even though humans like to plan everything down to the second.