You can go blind by staring at the sun

  Photo by Lykaestria

Everyone has heard the admonition against staring at the sun when they were kids. It seems logical; the sun is extremely bright. But can you really go blind?

The Sight and Hearing Association explains that "invisible UV light is the component of sunlight most responsible for eye damage. Excessive exposure to UV light from light reflected off sand, snow or pavement can produce a burn on the surface of the eye." According to How Stuff Works, "UV rays in sunlight cause irreparable damage and the cells die. Unfortunately for your eyes, there isn’t a way to replace damaged cells in the retina, so when someone stares at the sun, the cells in the retina die. And they they are dead for good."

Astronomy Blog decided to test this myth by holding a grape at the focus of a small telescope. After a few seconds the grape began to sizzle and then the outer layer gave way and hot grape juice squirted out. They posted a video of the damage occurring on their website.

DNA India reported in 2008 that:

At least 50 people have reportedly lost their vision after gazing at the sun looking for an image of Virgin Mary. St Joseph's ENT and Eye Hospital in Kanjirappally alone has recorded 48 cases of vision loss due to photochemical burns on the retina. "All our patients have similar history and symptoms. The damage is to the macula, the most sensitive part of retina. They have developed photochemical, not thermal, burns after continuously gazing at the sun," Dr Annamma James Isaac, the hospital's ophthalmologist, said. "Most patients may hopefully improve their vision. But there may be long-term effects on the retina."

So, while you may not go blind from a short look, serious damage is occurring and it's best not to take any chances. If viewing the sun, always be sure to take proper precautions.