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The eclipse will be cool, but not cool enough to be worth damaging your eyesight 

  • These solar eclipse glasses, spotted at my local general store, may or may not be safe to use watching the eclipse. I’m not going to take a chance, thank you. David Brooks—Monitor staff

  • As calculated by Vox media, this is what the sun willl look like in New Hampshire at maximum eclipse, 2:45 p.m. on Monday, Aug. 21.  courtesy—

  • All it takes to make a pinhole projector is a piece of paper with a pinhole in it and a piece of white paper, onto which you project the image. Courtesy

  • McAuliffe-Shepard Discovery Center senior educator R. P. Hale holds up the proper eclipse glasses that the center has for the partial eclipse Aug. 21. The center ran out of them but is expecting another shipment of 300 by Tuesday. For more information, visit starhop.com. GEOFF FORESTER / Monitor staff



Monitor staff
Tuesday, August 15, 2017

New Hampshire is going to be pretty far away from Monday’s solar eclipse, but the event will still be fun to watch – unless you’re victimized by the slimeballs selling unsafe eclipse-watching glasses, that is. 

Yes, it’s sadly true: Not even this delightful astronomical event is free from the taint of unscrupulous behavior.

The American Astronomical Society is warning people not to trust eclipse viewing glasses, even those bearing a label indicating that the product meets the ISO 12312-2 international safety standard for direct viewing of the sun, because of fakes “flooding the market.” Amazon said it would issue refunds for some eclipse filters bought through its site because they didn’t meet the standards they claimed to meet.

This is bad because using filters that don’t block out as much ultraviolet light as they claim can do serious damage to your retina that will last the rest of your life.

So be careful.

Definitely do not – repeat: do not – try to make your own eclipse glasses with film, smoked glass, or even welding goggles. These might dim the sun enough that you can look at it without pain, but that’s misleading. They don’t block the invisible UV radiation that causes the actual damage, and since you can’t feel the back of your eyeballs being zapped, you can’t judge whether they’re safe or not.

The AAS has an online list of “reputable vendors” for eclipse glasses at eclipse.aas.org/resources/solar-filters, but it’s not always easy to tell who made the glasses on sale. But frankly, unless you’re sure of your source – many libraries are giving away some glasses, and they’re for sale at McAuliffe-Shepard Discovery Center store – I’d skip the glasses entirely. Make a pinhole projector instead.

That’s what I did when I was lucky enough to be almost directly underneath the 1984 annular eclipse, a solar eclipse in which the moon is close enough to Earth that it doesn’t quite cover the entire sun, leaving a ring of light all around. It worked fine, as well as the eclipse glasses, plus I didn’t appear to be an escapee from a 3-D movie theater.

NASA’s Jet Propulsion Lab has directions about making a pinhole projector at jpl.nasa.gov, but it’s pretty easy. Basically, you punch a very small hole in one sheet of paper or cardboard – with, say, a pin! – then hold another piece of white paper or cardboard a couple of feet away. It’s a perfect way to watch the shadow of the moon eat up the sun and then spit it back out, with no fear of retinal disaster.

Mark Stowbridge, president of the New Hampshire Astronomical Society, pointed out a cool way to observe the eclipse many times over using multiple-hole pinhole cameras, both natural and manmade: “If you stand near a tree with light passing through gaps in the leaves, each bit of dappled light will become a crescent. (Or) you can hold up a piece of pegboard and make a whole field of miniature crescent Suns.”

And if you have a telescope, you can even set it up as an optical project that will project a bigger image of the sun onto a sheet of paper, as shown by the American Astronomical Society one at eclipse.aas.org/eye-safety/projection. But of course, don’t – don’t! – try looking through the telescope at the sun.

If this has you freaked out, you can watch with expert guidance at the McAuliffe-Shepard Discovery Center. It will host a bunch of eclipse events starting at 10:30 a.m. Monday, including guided viewing of the eclipse from 1:25 to 3:55 p.m. – it peaks about 2:43 p.m. Check the center’s website, starhop.org, for details.

And if you can’t tear yourself away from computer screens, NASA’s going to live-stream coverage with various vantage points on the ground and from aircraft, and even the International Space Station.

In New Hampshire, which is about 800 miles from the path of the moon’s shadow, we’ll see about 65 percent totality. That won’t affect daylight too much – don’t expect it to become like night time all of a sudden – but will still be cool to watch.

Unless it’s cloudy, of course. But let’s not think about that.

(David Brooks can be reached at 369-3313 or dbrooks@cmonitor.com or on Twitter @GraniteGeek.)