A Happy Sky over Bufa Hill in Mexico.

Sometimes, the sky itself seems to smile. A few days ago, visible over much of the world, an unusual superposition of our Moon with the planets Venus and Saturn created just such an iconic facial expression . Specifically, a crescent Moon appeared to make a happy face on the night sky when paired with seemingly nearby planets. Pictured is the scene as it appeared over Zacatecas , México , with distinctive Bufa Hill in the foreground. On the far right and farthest in the distance is the planet Saturn . Significantly closer and visible to Saturn's upper left is Venus , the brightest planet on the sky. Just above the central horizon is Earth's Moon in a waning crescent phase. To create this gigantic icon, the crescent moon phase must be smiling in the correct direction.

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