With a solar eclipse visible across the U.S. and beyond on Saturday, October 14 everyone wants to know the best places to see it, but there’s also a scramble for solar eclipse glasses. Many are wondering how to make them and how to view the solar eclipse without glasses.
Here’s the truth: solar protection filters are essential at all times for all people on Saturday. At no time will it be safe for anyone to look at the eclipse with the naked eye.
Rare Event
Observers of the rare celestial event will see something different depending on where they are. For example, for those are inside a path 125 miles wide going from Oregon through Texas, the main sight will be a “ring of fire” around the moon for a few minutes. That will occur in the middle of a partial solar eclipse lasting a few hours.
Everyone else in the U.S. (and in all of North, Central and South America) will see a partial solar eclipse of varying magnitude on Saturday.
Late Stage
At this late stage the best way to buy solar eclipse glasses is from a local shop (check the labeling for the logos of the main manufacturers, American Paper Optics, Rainbow Symphony/Thousand Oaks Optical), from a science museum or by attending a local eclipse observing event—many of which will have vendors selling safe solar eclipse glasses.
Here’s how to (and how not to) make solar eclipse glasses—and why there are many other, much safe ways of observing the sun.
How To Make Solar Eclipse Glasses
Nobody should be making their own solar eclipse glasses from things they find around the home. “Don’t do it,” said Dr. Ralph Chou, the world’s leading expert on eclipse eye safety who wrote the ISO standard for eclipse glasses, in an interview. “Yes, there’s a lot of aluminized polyester in consumer packaging, but it doesn’t have the density or the quality that you need to make a good optical filter.” Chou recommends only using solar eclipse glasses. “Don’t try to save a penny and risk your eyesight.”
Where To Get Free Solar Eclipse Glasses
Five-million pairs of solar-viewing glasses are being distributed for free to 10,000 libraries across the U.S. as part of the Gordon and Betty Moore Foundation-funded Solar Eclipse Activities for Libraries (SEAL) project.
Use this interactive map to find a library near you that may be giving out free solar eclipse glasses.
Don’t Use Sunglasses To Look At The Sun
Whether they’re polarized or just really dark, no pair of sunglasses is anywhere near up to the task of safely viewing a solar eclipse. “Sunglasses just block 10s of percent of the light—they are thousands of times too bright,” said Dr. Rick Feinberg, Project Manager, AAS Solar Eclipse Task Force at the American Astronomical Society, at a seminar on eclipse eye safety in June. “Solar filters are so dark they block one part in 100,000 and they also attenuate ultraviolet and infrared radiation.”
Using Welding Glass To Look At The (Green) Sun
Technically speaking you can observe a solar eclipse safely through some welding glass—but it’s not worth taking the risk. In the “what to avoid” section of a page on the American Astronomical Society’s website it states that the only welding filters that are safe for direct viewing of the sun with your eyes are those of Shade 13 or 14. Crucially, these are much darker than the filters used for most kinds of welding—so if you have something laying around at home it probably isn’t safe.
“Most welding supply stores do not carry Shade 13 and 14 as a regular inventory item,” said Chou. “It’s not the kind of welding that those customers would normally perform and although they can order it in, if the eclipse is in a few hours you’re not going to able to nip down to the shop and buy one.”
There’s also another downside to using welding filters—they make the sun look green!
How To Make A Safe Solar Eclipse Viewer
The safest way to view the solar eclipse if you don’t have solar filters is indirectly. Essentially you watch a projection of the sun rather than the sun itself. You can do that by using a pair of binoculars and a tripod to create a sun projector, using a telescope to build a sun funnel or simply project the sun through the holes of a kitchen colander or slotted spoon onto a plain surface. Even more simply, stand beneath a tree and the leaves will filter crescent suns onto the floor.
I’m an expert on eclipses—the editor of WhenIsTheNextEclipse.com and author of The Complete Guide To The Great North American Eclipse of April 8, 2024. For the very latest on the “ring of fire” solar eclipse check my main feed for new articles each day this week.
Wishing you clear skies and wide eyes.
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