Eclipse Glasses Safety
A total solar eclipse is about as bright as a full moon, and just as safe to look at. But that lasts only about 2.5 minutes at the center of the path and just a few seconds at its edges. There is 2-3 hours of partial eclipse to enjoy as well, but you must be prepared to view it safely.
Homeade filters of even very dark sunglasses are not safe. There are a variety of purpose made eclipse glasses on the market at a variety of price levels from around $1 cardboard ones which will probably only last for this big event to $15 or $20 ones that, with proper care could be useful again the morning of November 11, 2019 for the transit of Mercury.
Beware of cheap imitations though , especially as the date gets closer.
Make sure whatever you select meets ISO 12312-2 standards. Today four manufacturers have certified that their eclipse glasses and handheld solar viewers meet this international standard:
When buying online, also beware of what the search “eclipse glasses” brings up. Eclipse is a common name used for regular sunglasses. Some may mention that they met ANSI Z87.1 standards, and they probably do. But these aren’t nearly dark enough. This is an occupational safety standard focused on protecting workers eyes from impact, splashes and other hazards on the job, not the intense light of the sun.
I wouldn’t wait too much longer to buy glasses, and consider buy a few extra for family and friends. But you dont have a buy a thing to see the eclipse safely. More on that at eclipse2017.nasa.gov and on future weather brains episodes.
Category: ALL POSTS, Spacey Stuff