Thomas the little rabbit sat at his window, frowning at the sky. The night was quiet, only a gentle breeze rustled the leaves on the old apple tree. Everything would have been perfect, if... if the moon wasn't so strange. Just a few days ago, it had been like a giant silver ball, illuminating the entire garden. Today, all that was left of it was a thin, smiling sliver, like a piece of a banana someone had forgotten on the dark plate of the sky.
"It's not fair," he muttered under his whiskers. "Where did the rest of it go?"
The next morning, he had to tell his best friend, Lisa the squirrel, who was busy burying a nut under the roots of an oak tree with great concentration. "Lisa! Did you see the moon last night?" Thomas blurted out, out of breath. Lisa shook the dirt from her fur and twitched her ears curiously. "Of course, I did! It was so thin, I was afraid it might break. Do you think something ate it?" Thomas scratched behind his ear. "I don't know. And sometimes it's not in the sky at all. As if it's hiding somewhere. It's a mystery."
The two friends thought in silence for a while. They asked themselves questions that would occur to any curious observer. Does the Moon get tired and go to rest? Or is it playing hide-and-seek?
"You know what?" Lisa said suddenly, her eyes shining. "I know someone who might know. Professor Hoot!" Professor Hoot was an old, wise owl who lived on the highest branch of the oldest tree in the forest. He knew everything about the stars, the wind, and why the leaves change color in the autumn.
When evening fell and the thin crescent moon appeared in the sky again, Thomas and Lisa bravely set out for the old oak tree. Professor Hoot was sitting on his favorite branch, hooting softly into the night. "Good evening, Professor," chirped Thomas. "Good evening," Lisa added. "We have a very important question for you." "Hoo, hoo," the owl hooted amiably, turning his head almost all the way around. "Just ask, my little friends. Curiosity is the seed of wisdom."
"Why does the moon change?" asked Thomas. "Sometimes it's big and round, then it's just a tiny piece, and sometimes it disappears completely." Professor Hoot smiled his owlish smile. "An excellent question! It's not a mystery, but a wonderful celestial show. The Moon doesn't actually change. It's always the same size and shape, like a giant stone ball." Thomas and Lisa stared at him, confused. "But... we see it differently," Lisa objected.
"Come, I'll show you something," said Professor Hoot. He flew down to a clearing under the oak. He found a nice, smooth, and pale pebble, almost perfectly round. He placed it in the middle of the clearing. "Imagine this pebble is the Moon," he said solemnly. Then he called to a small firefly that was flitting nearby. "Could you help us for a moment, little firefly?" The firefly nodded and lit up its light. "And this," the professor said, pointing to the firefly, "is our Sun. The only great light in space that truly shines. The Moon doesn't shine on its own; it only borrows light from the Sun, like a mirror."
The professor asked the firefly to fly around the pebble in a wide circle, while Thomas and Lisa stood in one place and watched. When the firefly was directly behind them, shining straight onto the pebble's "face," the entire pebble was beautifully lit. "Look," said Hoot. "This is a full moon. You see the entire illuminated Moon." Then the firefly flew to the side of the pebble. Suddenly, Thomas and Lisa saw only half of it lit up. And when the firefly flew almost in front of the pebble, between it and their eyes, they could only see a very thin, glowing edge. Exactly like the crescent they had seen in the sky! "Aha!" exclaimed Thomas. "I get it now! We on Earth always see only the part of the Moon that the Sun is currently shining on!" "Exactly," the professor praised him. "And when the Moon gets right between us and the Sun, we don't see any of its illuminated part. That's when we say it's a new moon. And then it slowly begins to wax again, until it becomes a full moon once more."
Lisa jumped up and down with excitement. "That's amazing! So the moon doesn't disappear, it's just that its lit-up part is hidden from us." "Correct. And this celestial show has its own rules and repeats itself regularly," added Professor Hoot. "But the Moon doesn't just put on a show in the sky. It also has real power. Do you want to see what else it can do?"
Thomas and Lisa nodded curiously. Professor Hoot led them to the shore of a large lake, which shimmered like a dark mirror in the night. "Watch the shore carefully," he whispered. He showed them a line of wet sand and small pebbles. "You see how far the water reached today." They sat in silence for a while and watched. In the moonlight, they noticed that the water in the lake seemed to be slowly rising. It climbed higher and higher up the shore, until it passed the old line. "What's happening?" Thomas wondered. "Is it raining somewhere?" "No," the professor smiled. "That's the Moon, with its invisible force, pulling the water towards it. We call it high tide. And when the Moon moves further on its journey across the sky, its force weakens, and the water level drops again. We call that low tide. It happens every day in the seas and oceans, and just a little bit in our big lake here, too."
Lisa and Thomas were astounded. Not only had they solved the mystery of the Moon's changing shapes, but they had also discovered its secret power. "And why are some animals, like you, Professor, awake at night?" asked the curious Lisa. "Some of us have adapted to life in the dark," Hoot explained. "It's cooler and quieter at night. Bats hunt insects that fly in the dark, hedgehogs look for earthworms, and I have the best view of mice that run out of their holes. Everyone has their place and their time in nature."
As they were returning home, Thomas's head was full of new thoughts. He was no longer angry at the moon for changing. On the contrary, he looked forward to observing it every evening. "You know what, Lisa?" he said enthusiastically. "We could make our own moon calendar!" "Great idea!" Lisa agreed. "Every evening, we can draw what the Moon looks like!"
The very next day, they found a large, flat piece of dark bark. Using a white pebble, they began to draw on it. On the first day, they drew a thin crescent. On the second day, the crescent was a little thicker. A week later, a perfect half-moon was drawn on their calendar. They learned new words like first quarter and last quarter. They watched as the moon 'waned' and shrank after the full moon. They now knew exactly when the night would be darkest, because it would be a new moon, and when it would be brightest, because it would be a full moon.
Their small piece of bark became a map of the night sky. They never again wondered where the Moon had gone. They knew it was still there, just playing a wonderful game of light and shadow with the Sun. And with every glance up at the sky, they remembered the wise Professor Hoot and their nightly adventure.
"Look, Thomas," Lisa said one evening, pointing at their calendar. "According to our records, it will be a full moon tomorrow!" Thomas smiled. "Great! That means plenty of light for night games! And we know the water in the lake will be at its highest, too." It was no longer a mystery. It was their own little, shared secret that they understood. And that was even better.
And what about you, children? Will you try looking out your window tonight? What shape is the Moon right now?