On Monday, the moon’s shadow will block the sun from view in a total solar eclipse.
There’s one thing you shouldn’t do, and that’s look at the sun with your naked eye.
The only time you can look at the sun with your naked eye is A) if you’re in the path of totality, where the sun will be completely covered by the moon, and B) during those two minutes or less when the sun is completely covered.
Otherwise, looking directly at the powerful brightness of the sun can cause damage to the retina, the light-sensitive part of the eye by literally cooking it.
The safe way to view the eclipse is with filters that meet the ISO 12312-2 standard, which reduces the sun’s brightness to a safe and comfortable level.
However, unsafe eclipse glasses bearing the ISO logo and certification label have been flooding the market, according the astronomical society. Websites are also displaying false results that claim to show positive test results for glasses they sell.
“The only way you can be sure your solar viewer is safe is to verify that it comes from a reputable manufacturer or one of their authorized dealers,” the society said in a recent release. The organization has a list it keeps updated.
To test for safety, the only thing you can see through a safe solar filter is the sun itself. If you look through and the sun is too bright, out of focus or surrounded by a murky haze, or if you can see things like ordinary household lights, the glasses aren’t safe. Read more at CNN.