Fact check: Is there a safe way to watch the solar eclipse?
Published Tuesday, August 15, 2017 12:32PM EDT
Last Updated Sunday, August 20, 2017 4:17PM EDT
Optometrists, astronomers and doctors say it’s absolutely possible for kids and adults to safely observe the Aug. 21 solar eclipse through ISO-approved shades, despite a viral Facebook post urging everyone to simply watch it on TV.
Ohio optometrist Michael Schecter recently sparked fears with a Facebook post claiming that there is “no absolutely safe way to (observe the eclipse) other than on TV.” In his post, Schecter urged a better-safe-than-sorry approach to the rare astronomical event, particularly when it comes to children.
“One failure, just one, where education and supervision fail, will have such a devastating consequence,” Schecter wrote. He called watching the eclipse “a huge risk,” and suggested that one scratch or manufacturing defect in a pair of eclipse glasses could expose the viewer to light that will cause permanent vision damage.
The post has been shared more than 600 times on Facebook. The text has also been reposted on many people’s walls. “Please, please be safe,” Schecter writes. “Watch it on television.”
Is it true?
It’s certainly dangerous to look at the sun with the naked eye or through run-of-the-mill sunglasses, but that doesn’t mean the only safe solution is to watch the eclipse on TV.
Canadian optometry professor B. Ralph Chou, who helped develop the current International Organization for Standardization requirements for solar filters, says it’s entirely possible for anyone to enjoy the eclipse through a properly-vetted pair of solar shades. And that includes children.
“If they are properly supervised… they’re perfectly safe, just like adults,” Chou told CTVNews.ca on Tuesday.
And Chou is not alone. An overwhelming number of medical and astronomical experts say eclipse shades are safe to use, including top minds at NASA, the Canadian Space Agency, Health Canada, the U.S. National Eye Institute and the U.S. CDC. Great care should be taken to ensure that ISO-approved shades are used, but otherwise, experts say the rare phenomenon is a great educational event for children.
Schecter’s post echoes a common theme found among anti-vaxxers who distrust science and embrace a “better safe than sorry” attitude when it comes to their children.
Chou said he was amused by the social media hysteria over Schecter’s post, and stressed that eclipse glasses are perfectly safe, so long as children don’t try to peek around them.
“They need to use it properly,” he said. “Frankly, I don’t need the business.”
Which eclipse glasses are safe to use?
Sky-watchers should only look at the eclipse through ISO-approved shades that meet the ISO 12312-2 or ISO 12312-2:2015 international safety standard. This means they reduce visible sunlight to a comfortable level while also protecting the eyes against infrared and ultraviolent light. Approved shades will be clearly marked with the ISO 12312-2 label.
A true solar filter should be impossible to see through except when looking at the sun or an extremely bright light source, such as an incandescent light, Chou said. He says people should be wary of knockoffs, as many of their filters are far too light to protect against the sun.
He said the safest way to choose a pair of eclipse shades is to consult the American Astronomical Society’s list of approved vendors.
“I’ve reviewed all of them and made sure they’re legit,” he said.
He added that any shades marked with the EN 1836 standard are also safe to use. The standard was withdrawn in Europe when it was replaced by the current ISO a few years ago.
The AAS recommends checking your shades before the eclipse to ensure that they are safe. That means making sure they aren’t scratched, punctured or torn, as well as testing them on a bright light source to see if there are any flaws in the coverage. That way, you won’t be in a rush when the moment comes on Aug. 21, and you won’t be testing your eyes against the full intensity of the sun.
Still nervous? Use a pinhole viewer
For those who fail to get their hands on a pair of ISO-approved eclipse shades, a pinhole viewer is a fairly simple DIY alternative for observing the eclipse.
The Canada Space Agency website includes instructions for making your own pinhole viewer at home, using only a cardboard box, white paper, scissors, aluminum foil, a pin and some tape.
However, if you don’t have an arts and crafts section at your home or workplace, it’s also quite easy to make a simple projector using two sheets of white paper.
Simply puncture one sheet with a pin and hold it up with your back to the sun. Then hold the second sheet in front of the first, and an inverted image of the sun will be projected onto the second sheet.
When to watch
The eclipse will track across North America on Aug. 21, moving from west to east. It will be visible as a full solar eclipse in parts of the U.S., but part of the sun will remain visible in Canada throughout the day. Victoria is expected to see the most coverage, while Iqaluit will see the least.
The eclipse will reach its maximum point in the late morning on the West Coast, between noon and 1 p.m. in the Prairies, around 2:30 p.m. in Ontario and Quebec and shortly before 4 p.m. on the East Coast (all times local).