The solstice and seasons have nothing to do with how close Earth is to the sun. It's all about the stable tilt of its spin. It's the solstice again, which is an astronomer's favorite time of year. That's because it's one of the few occasions where we have anything semi-practical to say to anyone.
"Hey, Adam, you're an astronomer. What's this whole solstice thing about?"
Well, I'm glad you asked.
Let's start with why we have a solstice at all. The cool thing about this question is that it's really asking why we have seasons at all. There's a great documentary made years back where new graduates from Harvard are asked to explain the cause of Earth's seasons. Lots of them get the answer dead wrong. So if you don't know, you're in good company. Remarkably, Earth has seasons for the same reason that a good quarterback can throw a tight spiral. It's all about the stability of spinning things.
"Hey, Adam, you're an astronomer. What's this whole solstice thing about?"
Well, I'm glad you asked.
Let's start with why we have a solstice at all. The cool thing about this question is that it's really asking why we have seasons at all. There's a great documentary made years back where new graduates from Harvard are asked to explain the cause of Earth's seasons. Lots of them get the answer dead wrong. So if you don't know, you're in good company. Remarkably, Earth has seasons for the same reason that a good quarterback can throw a tight spiral. It's all about the stability of spinning things.