Q: Why are the days still longer than nights, until a few days after the fall equinox?
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Physicist: The issue here is the equinoxes are the two days of the year when the length of the day should be exactly as long as the night. And yet you’ll find that on the equinox the day is always slightly longer than 12 hours. Before the light from the Sun can get to us (here on the ground) it has to pass through the atmosphere. Basically, when light has to pass between a medium where it can travel fast (space counts) to one where it travels slower, the light will bend toward the slower medium. So, every day a handful of physical laws conspire to give us a couple more minutes of sunlight than you might otherwise expect (even on the equinoctes!