How to safely view the solar eclipse: tips, classes

Want to view the eclipse safely but aren’t sure how to do it?

The Lake Afton observatory is hosting classes on each of the next two Saturdays leading up to the Aug. 21 eclipse. While Wichita won’t be in the zone of total eclipse, the moon will still cover up to 93 percent of the sun here.

Harold Henderson, director of the Lake Afton observatory, said he is holding the Saturday information sessions because he’s worried eager viewers will harm their eyes.

“Eye safety during this eclipse is kind of a big thing,” Henderson said. A lot of people know that this one is coming up.

“That being the case, a lot of my concern is ‘Hey, don’t be using methods and questionable techniques ... you can do some damage to your eyeballs that will potentially last you the rest of your life.’ ”

The Lake Afton sessions, which cost $8 per person, will run from 1 to 3 p.m. each Saturday. Henderson said he plans to show participants how to view the eclipse indirectly, so they can protect their eyes from damage resulting from looking directly at the sun.

There are a lot of “eclipse glasses” on the shelves and the Internet, he said. People may not be sure how to choose glasses that are safe and avoid cheap knock-offs that don’t provide the eye protection that’s needed.

NASA recommends buying eclipse viewing glasses from any one of just five companies: American Paper Optics, Baader Planetarium, Rainbow Symphony, Thousand Oaks Optical and TSE 17. American Paper Optics is the largest of those companies, with sales reaching 500,000 pairs of glasses per day in the weeks leading up to the eclipse, according to USA Today.

NASA also recommends eclipse viewers ensure that the ISO certification number 12312-2 and the manufacturer’s address are printed on viewing glasses.

Solar eclipse glasses can be bought in stores, including some Walmart and Lowe’s Home Improvement locations, according to the American Astronomical Society, which helped NASA compile a list of reputable manufacturers.

But glasses from companies not recommended by NASA are readily available online, where it is sometimes hard to tell the difference between safe and potentially risky glasses.

When buying glasses in person, Henderson said to look for lenses that are a little darker than welding glasses.

“The easiest thing to do is, inside the store, find the brightest light source you can find,” Henderson said.

Put the glasses on and look at the light. The only thing you should see is the glowing filaments in the lights. If you see more than that, he said, the shades aren’t dark enough and you could damage your eyes.

A “table lamp test” is also a good way to check eclipse glasses, he said.

“If you can see light coming through them with your typical table lamp,” he said, “they’re not dark enough.”

This story was originally published August 10, 2017 at 12:17 PM with the headline "How to safely view the solar eclipse: tips, classes."