Why does staring at the sun hurt

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Continue reading with a Scientific American subscription. Solar retinopathy, as the damage is known, may not be painful like photokeratitis—but the results can be permanent. When the light-sensing cells of the retina are overstimulated, they release a flood of signaling chemicals. In sufficient concentrations, like during a long look at the sun, these can damage surrounding tissue. This condition is typically reversible over time—from one month up to a year, depending on the amount of damage sustained.

In some cases, healing progresses steadily over the course of 12 months. In others, it heals rapidly in the first month, then remains static for 18 months before improving again. With enough damage to the retina, though, staring at the sun can leave you partially blind. Prolonged UV exposure can damage the macula, a tiny substructure of the retina responsible for the majority of your central detail vision. The pupil will naturally contract when exposed to bright light, but the amount of light still entering the eye is concentrated on the macula tissue.

Damaging it can cause macular degeneration, eventually resulting in permanent blindness in the center of your field of vision. Basically, that black dot you see after a photo flash would just never go away. We see those waves as colors. Different wavelengths show up for us as green, yellow, blue — all the colors of the rainbow. Infrared radiation has wavelengths that are too long to be visible to us.

Ultraviolet radiation has wavelengths that are too short. But when the lens blocks UV radiation, that energy has to go somewhere. Instead of passing through the cells that make up the lens of the eye, the oscillating particles crash into them, damaging the cells, and causing the pain of photokeratitis, Jeffery told me. That was a pretty crazy idea. The re-evaluation started with rodents , which turned out to have light-sensing cells in their eyes that could see light with a wavelength of nanometers — UV light is defined as light with a wavelength between about nanometers and 10 nanometers.

Light is visible to humans when the wavelengths are to nanometers. He contacted a bunch of zoos and asked them to let him know anytime they had a mammal that died. When they did, he requested that the zoo extract an eyeball, freeze it and send it to him. Scientists get very interesting mail. He ended up with eyeballs from 38 species.

Is it possible to heal sun damage? How can you protect yourself? Surgery is a routinely safe and successful option for removing pterygia and pingueculae, and reversing the effects of cataracts.

The best thing you can do for your eyes is take measures to shield them from sun damage. Preventing UV rays from gaining access to your eyes will save you a lot of trouble in the long run.

Wear sunglasses with maximum UV protection : Not all sunglasses offer the same level of protection against harmful UV rays. For an added level of sun protection, consider wrap-around sunglasses, which also protect your peripheral vision.