Why Do Stars Twinkle But Planets Don't?

Stars twinkle because their light has to pass through the Earth's atmosphere, which is full of moving air. Think of it like a glass of water with bubbles, when you look at something through that water, it looks wobbly and shaky. Stars are far away, so they seem more affected by the bubbles in the air. Planets are much closer to us, so their light is less disturbed by those same bubbles, making them appear steady.

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Examples

  1. A bright light from across the room looks steady, but if it’s far away like a tiny flashlight in the distance, it might flicker when you look through a glass of water.

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