Aug 18, 2017


Interviewer: On August 21st, the so-called "great American total solar eclipse" will darken the skies. How to keep your eyes safe during this cosmic event, next on The Scope.

Announcer: Health tips, medical news, research, and more for a happier, healthier life. From University of Utah Health Sciences, this is The Scope.

Interviewer: We're here with Dr. Jeff Pettey, he's an ophthalmologist with University of Utah Health. Now, Dr. Pettey, what are some of the things that can happen to a person if they look at an eclipse unsafely?

Dr. Pettey: An eclipse is essentially the moon blocking the sun, a solar eclipse. And if you are watching an eclipse during the time period that the moon is entirely blocking the sun, it's safe to look at that point. At that point, it will begin to darken, some of the stars will come out and at that point, it will just be like dusk and you can look directly at the moon covering the sun. At any other point during an eclipse, you will have eye damage if you look at the eclipse for too long. It's basically like you're looking at the sun during an eclipse.

Interviewer: And we all know not to stare at the sun. But do you happen to know how long that moment of, "It's okay to stare directly at the eclipse," is?

Dr. Pettey: Yeah, we don't know, we don't know exactly how long. There are estimates of perhaps a minute, and some people say a few seconds. The bottom line is there's really no amount of time which we would recommend that you look directly at the sun or directly at an eclipse.

Interviewer: Officially, right?

Dr. Pettey: Yes.

Interviewer: All right, so how are some of the ways that all of these people running and flocking to different places to take a look at this, you know, this eclipse, what are some of the ways they can do it safely?

Dr. Pettey: The only way to look at the sun or at the eclipse safely is with something that's going to dim out the rays, and that's with something called eclipse glasses or eclipse shields. They're going to block out all but about a millionth of the sun's rays. And when you have a pair of eclipse glasses on and you look at the sun, all that you should be able to see is the sun or, during an eclipse, the partial portion of the sun that's not blocked by the moon.

Interviewer: When purchasing these types of glasses, maybe it's the first time someone's even experienced an eclipse like this, what are some of the things that people should be looking for to make sure that they are safe in their purchase when they're looking?

Dr. Pettey: Yeah, here's really the crux of it. What's happened recently is sellers such as Amazon, they've been selling eclipse glasses. These eclipse glasses reportedly had the International Organization for Standardization, ISO, certification certifying that they're safe to look the sun or an eclipse. And what they've found is some of these vendors have not been able to actually verify that they've received this standardization. So people, like myself, have received emails from Amazon saying while they might be safe, they do not recommend using these glasses to look at the eclipse because they can't verify that they would be safe.

So on to the important question. How can you actually know? Well, the American Astronomical Association has published a group of reputable vendors that they have utilized, that can be found on their website. Short of that, at this point, if you do happen to have a pair of eclipse glasses and you're not certain whether they're safe to use, you likely will be okay. However, that's something that we can't promise.

Interviewer: So kind of, final word, if you're going to be looking at the eclipse, don't look at it directly without some sort of protection.

Dr. Pettey: That's correct. And the safest thing to do if you don't have any access is to make a pinhole camera. You can find pinhole cameras how-tos all over YouTube, all over the internet. Essentially, take something, poke a hole in it, and then allow the sun's rays to go through that hole and look at the projection behind it and you'll be able to see the eclipse.

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