Solar eclipse glasses from B&H Photo, GreatAmericanEclipse.com, Spectrum Telescope and Agena Astro Credit – Illustration by TIME
JAn Mars is so excited about the upcoming solar eclipse that she has purchased 1,200 branded solar eclipse glasses for her customers and friends.
“Man, it was definitely one of those things you’ll remember for the rest of your life,” says the 58-year-old real estate agent from Collierville, Tennessee, who witnessed her first total solar eclipse in 2017. “I was watching when the next [solar eclipse] was on his way home from there. I saw that [my brother’s ranch] would be in the middle of totality and I called him and said, ‘I hope you’re really enjoying your ranch because you gotta keep it until then.’
But where you buy your glasses before the April 8 solar eclipse is important. Unsafe eclipse glasses were a major problem in 2017, prompting online retailers like Amazon to issue refunds and face lawsuits from customers who purchased unsafe glasses. (The case was later dismissed by the court.)
Here’s everything you need to know about how to buy solar eclipse glasses, how to get them for free, and how to avoid counterfeits.
How to buy safe solar eclipse glasses
Before purchasing solar eclipse glasses or binoculars, make sure the items come from the American Astronomical Society’s (AAS) list of trusted suppliers. While the AAS previously issued a press release stating that most eclipse glasses are safe to use, the group recently discovered counterfeit glasses that did not meet ISO 12312-2 standards that dictate how much ultraviolet and infrared light can pass through the glasses. filters.
“It’s not smart to just search for eclipse glasses on Amazon, Etsy, eBay or Google and buy whatever pops up,” says Richard Fienberg, project manager of the American Astronomical Society’s Solar Eclipse Task Force. “There are companies that sell eclipse glasses under false pretenses. The two most likely false pretenses are that the glasses have not actually been properly tested and have not been found to be safe, or that the glasses are made in China but are printed with information saying they are made in America. Where the glasses are manufactured is important because the glasses must be tested with special equipment in an accredited laboratory.
As part of the Solar Eclipse Task Force, Fienberg reviews companies’ test reports and verifies their distributor, along with performing a series of other checks, before adding them to the AAS list. (The list is not exhaustive, which means there may be other sellers from whom you can safely buy.)
“If you see a company claiming to be on the AAS list, and you go to look at the AAS list and they’re not on it, that should tell you something,” says Feinberg. “Maybe they were already there in 2017. But we cleared the list and started all over again a few years ago.”
Amazon tells TIME that all solar eclipse glasses they sell must be ISO compliant and come from the AAS list. “We continuously monitor our store and if we discover that a product has not been detected by our automated checks, we immediately address the issue and refine our checks. “We are taking action to maintain a safe selection for our customers, including removing non-compliant products and contacting sellers, manufacturers and government agencies for additional information as necessary,” an Amazon spokesperson said.
Testing for defective eclipse glasses
Given the unreliable market, Fienberg suggests that customers test their eclipse glasses before April 8 to ensure they have a safe pair. To do this, he says to first wear their eclipse glasses indoors. If you can see the room and objects around you, it means that your glasses are not dark enough and do not protect you sufficiently from the sun.
“There are some very bright lights that you might be able to see through – like an old light bulb, you might be able to see the filament, [or] if you have a halogen lamp,” says Fienberg. “If you look through it and you can’t see anything, you can actually go outside and take a very quick look at the sun and probably find that the visibility is good, it’s sharp, it’s not too bright, not too dim . Then you should feel beautiful, quite confident that they are safe.
How to get free eclipse glasses
According to the AAS, the STAR Library Network distributes five million eclipse glasses to more than 13,000 U.S. public libraries. Interested customers can check with their local library to see if they have received any free pairs, and can also check possible locations with this map.
Some ophthalmologist offices, including MyEyeDr., give out free eclipse glasses at select locations. Warby Parker is also offering free pairs in all stores from April 1.
New York Governor Kathy Hochul announced Tuesday that the state will distribute free, limited edition “I love NY” eclipse glasses at 30 locations. Here you can view distribution centers. Also check to see if your local county or city offers free eyeglasses. For example, residents of Chautauqua County, New York can get glasses at a number of locations.
You might also be able to grab a few at your local viewing party. Republic Square in Austin, Texas is handing out free solar eclipse binoculars to the first 200 guests in attendance.
When should you use eclipse glasses?
Although you can view the solar eclipse with your naked eyes once the moon completely covers the sun or reaches totality, you will need to use solar eclipse glasses or binoculars during the partial phases of the eclipse. This means that your eyes will need some kind of protection for the estimated hour leading up to (and the estimated hour following) the eclipse.
Fienberg says those outside the path of totality — the approximately 115-mile-wide path from which the total solar eclipse will be visible in fourteen states — will need to use protection throughout the event.
Fienberg says people can use solar eclipse glasses with their contact lenses or prescription glasses, but they shouldn’t use other objects to get a better look at the sun. “It’s dangerous to put on eclipse glasses and then pick up a pair of binoculars and look through them,” he says. “If you do that, the extra light-gathering power of those big front lenses on your binoculars will collect so much light that it will burn through the solar filter and through your eye.”
Can you use old eclipse glasses?
If you have eclipse glasses from previous solar eclipses that crossed the US in 2017 and 2023, you can still use them safely in 2024, says Fienberg.
However, the AAS advises people to inspect their old lenses for holes, cracks, scratches or other damage. Older solar eclipse glasses can only be used if they are in good condition, the lenses have not come loose from the frame or have no other problems.
What if you don’t have solar eclipse glasses?
Those who don’t have eclipse glasses can still have a fun viewing experience by using pinhole projection. Instructions for making a pinhole projector can be found here.
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