When you look up at the blue sky and see white dots flying around, you're actually seeing your own white blood cells.

When you look up at the blue sky and see white dots flying around, you’re actually seeing your own white blood cells.

Turns out, the blue field entoptic phenomenon is a real and, according to the US-based American Academy of Ophthalmology (AAO), normal occurrence. Moving dots in vision after staring at the sky are “created by your own white blood cells flowing through your eyes”, the academy says.

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