Solar eclipse viewing: What to wear to protect your eyes

As anticipation for the August 21 total solar eclipse builds across the U.S., NASA is issuing a warning: don’t be reckless with your eyes. 

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NASA

The total solar eclipse —  a much-anticipated celestial event in which the moon completely obscures the sun, transforming day into night — is expected to be visible to anyone within a roughly 70-mile-wide path stretching from Oregon to South Carolina. Those in other areas of North America will still see a solar eclipse, but only a partial one. 

It will be the first total solar eclipse visible from coast to coast in the continental U.S. since 1918, and millions of Americans are looking forward to catching a glimpse.

But the safety stakes are high. A solar eclipse, viewed without adequate eye protection, is powerful enough to blind you. Even the smallest sliver of a crescent sun peeking out from behind the moon is enough to potentially permanently scorch your retinas, according to ophthalmologists.

Viewing the total solar eclipse requires specific eclipse glasses or hand-held solar viewers. Regular sunglasses won’t do the job. According to NASA, there are only four eclipse glasses and solar viewers on the market certified to meet international safety standards:

Be sure to inspect your solar filter before the eclipse, and don’t use it if it’s scratched or damaged, the experts advise.

Another option is to view the eclipse through #14 welder’s glass. That’s much darker than the shades arc welders typically wear, and NASA warns that only #14 or darker is adequate to protect your eyes in an eclipse.

NASA’s strict advice: Unless you’re in the narrow zone where the eclipse will be total, keep your special glasses on throughout the eclipse. The only time it’s safe look without glasses is during the moments of totality, when the sun is completely and totally blocked by the moon — and beware, that phase may only last a minute or two in some locations. 

NASA’s local listings detail when the total solar eclipse with start and end at different locations across the country. 

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The solar eclipse of 2017 will darken skies from coast to coast on Aug. 21 along a 70-mile wide “path of totality.” But viewers anywhere in the United States will be able to enjoy at least a partial eclipse with the moon covering half of the sun or more.

NASA

As the moon moves across the sun, the lower atmosphere of the sun will slowly begin to peek out in the shape of a crescent, according to NASA. That is the signal to stop looking directly at the eclipse and again grab your glasses before the first flash of sun emerges around the moon’s edges.

You could also consider observing the eclipse through a pinhole camera. NASA has more detailed safety information here

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