Omie & Irie and the Four Seasons
One sunny afternoon, Omie was very busy being hot. He had taken off his socks, his hat, and one shoe, and he was still hot.
"Why is summer so hot?" he asked his big sister Irie, fanning himself with a leaf.
"And why is winter so cold?" Irie added, because she had been wondering the same thing. "Is the Sun closer to us in the summer, and farther away in the winter?"
It seemed like a sensible idea. When you stand close to a campfire, you feel warmer. When you step back, you feel cooler. Maybe the whole Earth did the same thing with the Sun.
The Flashlight Experiment
Irie fetched two things from the house: a big round beach ball, and a flashlight.
"Pretend this ball is the Earth," she said, "and the flashlight is the Sun."
Omie held the flashlight very still, the way a Sun should. Irie held the ball straight up and down, and shone the light right at its middle.
"See? The light hits the middle straight on," Irie said. "That part gets the most light, so it's the warmest."
Then Irie tilted the ball a little, the way the real Earth leans in space. Suddenly the light did not hit the top and the bottom the same way at all.
The Leaning Earth
The Seasons Lesson: The Earth does not stand up straight as it travels around the Sun. It leans — always tipped to one side, like a spinning top that never quite straightens up. That lean is what makes the seasons!
When your half of the Earth leans toward the Sun, the sunlight hits you straight on, strong and direct, and the days are long. That is summer. When your half leans away from the Sun, the sunlight comes in slanted and spread out, like butter scraped thin across toast, and the days are short. That is winter.
And here is the surprising part: the Earth is actually a tiny bit farther from the Sun during summer in the Northern Hemisphere, where Irie and Omie live. Distance is not what makes the seasons. The lean is!
A Walk Around the Year
To celebrate their discovery, Irie and Omie took a walk around the garden, pretending each corner was a different season.
In the spring corner, they sniffed imaginary flowers and counted baby leaves. In the summer corner, Omie spread his arms wide and declared himself "the Sun." In the autumn corner, they crunched pretend leaves under their shoes. And in the winter corner, they shivered dramatically and pretended to catch snowflakes on their tongues.
"Spring, summer, autumn, winter!" Irie chanted, hopping from corner to corner. "All because the Earth leans!"
Omie hopped after her, chanting, "Lean! Lean! Lean!" and then fell over, which is also a kind of leaning.
The Season Wheel
Back inside, Irie drew a big circle on a piece of paper and divided it into four parts. She colored one green for spring, one yellow for summer, one orange for autumn, and one blue for winter. Then she drew a little Earth in the middle, leaning politely to one side.
"This is our Season Wheel," she said. "So we never forget."
Omie studied it very seriously, then added his own contribution: a small drawing of himself, in the summer corner, eating an ice pop.
That night, as they looked out the window at the stars, Irie whispered, "Somewhere up there, the Earth is leaning right now."
"Leaning toward summer or away from it?" Omie asked.
"That," said Irie, "depends on which side of the world you are standing on. And that is the wonderful thing about a leaning planet — somewhere, it is always somebody's summer."
And from then on, whenever someone asked Omie why summer was hot, he would tilt his whole body to one side, grin, and say, "Because the Earth leans!"