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Why Do I Sometimes See Tiny Moving Dots?

Those tiny dots are actually blood cells moving in the retina of your eye.

statue staring at the sun

Photo: Matt Mendoza (flickr)

It's best to relax and stare at the sky because when your eyes focus on an object at any particular distance, you won't be able to see the retina of your own eyes.

Lie back on a cloudless day and let your eyes rest on a deep blue sky. As you relax and stare at the sky, you should begin to see faint dots of light moving quickly around. It may take ten or fifteen seconds before you begin to see the dots. Or they may look like tiny flashes of light.

However they appear to you, those tiny dots are really blood cells moving in the retina of your eye.

What’s Going On?

At the back of the eye in the part called the retina, are the photoreceptor cells that detect light and send signals through the nerves to the brain.

In the eyes of invertebrates, like insects, snails, and spiders, the nerves go straight from the back of the eye to the brain.

In the eyes of vertebrates, such as mammals, birds, and reptiles, the path that the nerves take from the photoreceptors to the brain begins at the surface of the retina in front of the photoreceptors.

Those nerves then come together to form the optic nerve, passing through the retina on their way to the brain.

Detecting Light

What this means is that there is a layer of nerves between the retina and the light that the retina is detecting. But to operate, the nerves need blood and so tiny blood vessels also flow across the surface of the retina.

A spider looking at the sky wouldn’t see the tiny flashes because there are no blood vessels between its photoreceptor cells and the sky. But when you look at the sky, you can see your own blood cells moving across your retina.

It’s best to relax and stare at the sky because when your eyes focus on an object at any particular distance, you won’t be able to see the retina of your own eyes.

  • Doug McKinney

    But what about floaters, These “tiny moving dots” can be caused by other other things as well. They can be benign or they can be a sign of a serious condition such as a detaching retina.

  • Rõhān G. Vǽdyā

    Really a phenomenal article.

  • Silent Koala

    i see this all the time. but what if its not just an illusion? what if those particles of light are actually high frequency positively charged electrons emanating from the sun? the sun emits high frequency electricity at close to a million volts that beam to our planet and get trapped in our atmosphere. if you think about this, it becomes clear how lightning can be produced, and how the aurora borealis is made

  • Silent Koala

    could be. but what i see can ONLY be seen in the sky during sunset or sunrise. if it were a condition brought upon by our retinas we should be able to see the same things on the backs of our eye lids. but i don’t.

  • pizzahutdude

    But mine aren’t in a controlled motion. They fly around everywhere and dont seem to follow a pattern. If they were in a vessel, wouldnt they follow the same paths or at least some would repeat? Mine go all different directions, sometimes in collision courses with others. Also wouldn’t an object such as a blood cell in between the light source and the receptor block light and cause the spots to be dark? Even so the “particles”, as I call them, seem to be energized. If light was being blocked then how do they appear brighter than the light behind them (sky)? I think that it is some type of atmoshperic reaction, whether it be some type of particle or physical reaction from something coming in from space (dust, micrometorites etc.) Maybe it is just free floating energy like Tesla theorized about?

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