More than 300 million people in the United States may be watching on August 21 when the total solar eclipse occurs. In Oregon, 4 million residents and an estimated 1 million visitors will watch the moon pass in front of the sun in what NASA, the National Aeronautics and Space Administration, calls “a spectacular sky show.”

Eclipse glasses are being sold in nearly every Salem venue imaginable – including fast food restaurants – because serious retinal damage can result when people look at even the smallest area of the sun during the eclipse process.

NASA issued info on what to look for in eclipse glasses in late July.

“Only with special-purpose solar filters,” NASA says, “such as eclipse glasses or a handheld solar viewer, you can safely look directly at the Sun.“

NASA recommends that anyone viewing the eclipse should check their viewing glasses ahead of time. Eclipse viewing glasses and handheld solar viewers should meet all the following criteria:

· Have certification information with a designated ISO 12312-2 international standard

· Have the manufacturer’s name and address printed somewhere on the product

· Not be used if they are older than three years, or have scratched or wrinkled lenses

· Not use homemade filters

· Ordinary sunglasses — even very dark ones — should not be used as a replacement for eclipse viewing glasses or handheld solar viewers.

Some glasses are not made to spec and are marketed by fraudulent companies. For a list of reputable sources, check with the American Astro Nomical website, and more information is available on the NASA website.