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As the total solar eclipse approaches on April 8 in Mexico, the United States and Canada, experts are reminding viewers to buy a pair of eclipse glasses to safely view the celestial event and make sure they’re not fake.
Fake eclipse glasses are “polluting the market,” according to a statement shared by the American Astronomical Society (AAS).
A total solar eclipse occurs when the Moon comes between the Earth and the Sun, completely blocking the Sun’s face for a while. About 32 million people in the United States live within the 115-mile-wide (185-kilometer-wide) path of totality, or places where the Moon will appear to completely cover the sun and the lunar shadow falls on the Earth’s surface. People outside the path of totality will still be able to see a partial solar eclipse, where the moon covers only part of the sun’s face.
According to NASA, the only time it is safe to see the sun without eye protection is during a total solar eclipse or a brief period when the moon completely blocks sunlight.
Otherwise, experts say it is absolutely necessary to wear certified eclipse glasses or use handheld solar viewing devices that meet a specific safety standard known as ISO 12312-2 when viewing all other phases of a total or partial solar eclipse. The safety standard means the lenses meet international requirements for direct sunlight imaging, according to AAS.
The lenses of solar eclipse glasses are made of black polymer, or resin infused with carbon particles, that blocks nearly all visible, infrared and ultraviolet light, according to The Planetary Society. And sunglasses will not work as a substitute for eclipse glasses or sunglasses.
“Sunglasses, smoked lenses, telescopes or magnifiers without filters, and polarizing filters are unsafe. According to a statement from the American Optometric Association, inspect your Eclipse glasses or handheld viewer before use; Discard the device if it is torn, scratched, or otherwise damaged.”
Looking at the sun without eclipse glasses can cause serious eye injuries, from temporary visual impairment to permanent blindness. However, AAS discovered that fake solar eclipse glasses were being produced that did not provide the protection needed to see the sun safely without damaging the eyes.
How to spot fake Eclipse glasses?
According to the AAS, fake glasses can be difficult to spot because they contain information and even original artwork that indicate the products were made by a known reputable manufacturer, but different as-yet-unidentified factories actually produced them.
“Until recently the only counterfeit product we knew of was one manufactured by an unidentified factory in China but labeled ‘Mfg.’ They were sunglasses with cardboard frames printed with a label. “American Paper Optics’ (APO) is about them,” AAS shared in a news release. “APO is one of the largest U.S. manufacturers of safe solar imaging devices and prints its name and address on its solar eclipse glasses, while counterfeit products in China have APO’s name but no address. “Fortunately, these fake products appear to be safe.”
However, close monitoring by AAS revealed that more unidentified factories were identified as Cangnan County Qiwei Craft Co., which produces safe products. It was revealed that the Chinese factory named was producing fake glasses with its name and address printed on it. Some of the fake glasses also feature the name or logo of Solar Eclipse International of Canada, Qiwei’s North American distributor.
While some glasses appear safe and virtually indistinguishable from genuine Qiwei products, others have lenses as dark as sunglasses, meaning they are unsafe to use, according to the AAS.
“Filters that provide safe and comfortable views of the Sun typically transmit between 1 in 100,000 (0.001%) and 1 in 2,000,000 (0.00005%) of visible light,” said Rick Fienberg, AAS Solar Eclipse Task Force project manager. said. , in a statement. “Solar filters are at least 1,000 times darker than even the darkest tinted regular sunglasses.”
AAS has compiled a list of safe manufacturers and vendors of Eclipse glasses and filters for optical devices, including cameras and smartphones. The AAS task force for the eclipse confirmed that solar imagers and glasses made by all known manufacturers in the US and Europe, as well as some Chinese manufacturers, were tested in a laboratory.
“If you now want to buy sunglasses, we recommend that you only buy from sites you reach by clicking the links in our list or from a seller whose identity you can verify and whose name appears on our list.” AAS. “We recommend that you do not buy eclipse glasses from random sellers on online marketplaces, even if they claim to source their products from a supplier on our list or are approved by AAS or NASA. The US space agency does not approve or approve commercial products; therefore, any claims to the contrary are a warning sign that you are not dealing with a trustworthy vendor. Similarly, if a vendor claims to be on the AAS supplier list but you cannot find it on the list, you should not trust it.”
Tips for viewing the eclipse safely and testing your glasses
For those who don’t purchase their glasses directly from listed authorized dealers, there are ways to test the Eclipse glasses before April 8.
“There’s no way to tell if eclipse glasses are actually safe just by looking at them,” Fienberg said, “but it’s easy to tell whether they are.”
Try the glasses indoors first. Nothing should be visible through the lenses and even the brightest lights should appear very faint. If furniture or wall decorations are visible through the lenses, these glasses are not safe for viewing the sun.
But if the glasses pass the indoor test, the AAS recommends wearing them outside on a sunny day and looking around. Again, nothing should be visible through the lenses unless the sun is reflecting off an extremely shiny surface, and even then the light will appear faint if glasses are safe.
If the glasses pass the second test, try looking at the sun through the glasses for less than a second. If the glasses are secure, the sun will appear comfortably bright and possibly white, yellow, orange or bluish-white.
On the day of the eclipse, stand still and cover your eyes with glasses or sunglasses before looking up. And never take off your glasses when looking at the sun. For those who wear glasses, put eclipse glasses on them or hold a handheld viewer in front of them.
Do not forget to equip camera lenses, binoculars or telescopes used to observe the eclipse with appropriate solar filters. In this case, never look through an unfiltered optical device, even if you are wearing eclipse glasses.
Avoid eclipse eye damage
It is only safe to view the eclipse without eye protection when the moon has completely blocked the sun and no light is visible, and be sure to put your eclipse glasses back on before any light reappears.
Looking at the sun without proper eye protection can cause solar retinopathy, or retinal damage due to sun exposure. While the highly specialized cells inside our eyes don’t feel any pain, the rods, cones and photochemical reactors become inflamed and damaged when looking at the sun, said Ronald Benner, an optometrist and president of the American Optometric Association.
This is somewhat similar to the effect that occurs when we see a camera flash go off, which can distort our vision for several minutes before disappearing. However, the intensity of solar retinopathy causes permanent damage that may not be immediately noticeable. Overnight, cells may die and new ones will not regenerate. There is no cure for solar retinopathy. It may get better or worse, but it is a permanent condition.
Changes in a person’s vision depend on the type of damage that occurs, and they may occur in one or both eyes.
“The retina is an extension of the brain, so it’s actually neurological tissue, and when you damage it, it doesn’t always come back,” Benner said. “If you damage a cell, that cell may never be the same again. But if you damage a group of cells, you’ll be left with smeared vision, like someone putting oil on your windshield. If you damage them a little and they do not die completely, then color vision will change. What can you do about this? “It is absolutely nothing but obstruction.”
If the damage occurs in a person’s center of vision, it can affect their ability to read or recognize faces, Benner said.
If you experience vision problems or eye discomfort after viewing the eclipse, Benner recommends making an appointment right away using the American Optometric Association’s doctor locator tool. Symptoms can take hours to several days to appear and include loss of central vision, change in color vision, or visual impairment.
“For most people, this is a change in color vision,” Benner said. “The next morning the colors don’t look quite right, they may be faded or constantly hazy. “And some may actually have holes in their vision.”
Always keep your eyes open to make sure that children wearing eclipse glasses do not take them off and look directly at the sun. Benner recommends that parents talk to their children about how and when they can watch the eclipse and when they can take off their glasses. If parents are worried their child might take off their glasses at the wrong time, make plans to watch the eclipse on television or use pinhole projection to view the eclipse indirectly.
“Make sure you protect not only yourself, but more importantly, your children,” Benner said. “If your child’s eye is damaged, he will have to live with it for the rest of his life. And they may not be able to tell you, ‘I can’t see clearly in one eye.'”
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