Why do stars twinkle?
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What shapes do you imagine the twinkling stars could make in the sky?
What about...?
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Transcript
Have you ever looked up and wondered, why do stars twinkle?
A star sends its light all the way to Earth. The light travels through the air around our planet.
Our air is always moving, with warm and cool parts. These moving parts bend the star's light a tiny bit.
The bent light reaches our eyes in little changing bits. So the star can look like it is blinking and twinkling.
So that's why stars twinkle. Moving air bends their light on its trip to our eyes!
For grown-ups: the science
Stars twinkle because moving air bends their light a little before it reaches our eyes.
Stellar scintillation is caused by turbulence in Earth's atmosphere. Small, changing pockets of air with different temperatures and densities slightly change the path and brightness of starlight. Stars are so far away that they appear as tiny points, making the effect easy to see.