The Earth, the sun, and the moon all orbit in space in predictable paths. On August 21, 2017, there will be a celestial alignment of the three resulting in a solar eclipse. The moon will move between the sun and the Earth blocking the light of the sun. Thus, the moon will cast a shadow on the Earth. Some lucky areas of Georgia will experience a total solar eclipse while most of us will experience a partial eclipse. This is a wonderful educational moment for all of us no matter where we live, but it can also be dangerous if one looks directly at the sun. Student Safety: Most of us know we should not look directly at the sun, but during an eclipse, our curiosity and wonder can overtake our common sense. We just want to look up! Below is critically important information for our students and community about how to safely view an eclipse. This event will be happening around school dismissal time. Student Safety is Critical: Our schools are being proactive in sharing this information with students and reinforcing safety measures as we approach the eclipse date. After school sports practice times are also being altered on this date. The #1 rule for observing a solar eclipse, or for looking directly at the Sun at any other time, is safety first. As noted elsewhere on this site, with one exception, it is never safe to look directly at the Sun without a special-purpose safe solar filter. That exception is during totality, when the Moon completely blocks the dazzlingly bright face of the Sun. On August 21, 2017, this will happen only within the roughly 70-mile-wide path of the Moon’s dark inner shadow from Oregon to South Carolina — and only for a minute or two. Before and after totality, and at all times outside the path of totality, you must use a special-purpose safe solar filter when looking directly at the Sun. “Special-purpose” means designed exclusively for looking directly at the everyday Sun. Filters for direct viewing of the Sun are typically sold in the form of wearable “eclipse glasses” or “eclipse shades” or as solar viewing cards that you hold in your hand. What makes them special is that they reduce sunlight to safe levels so that you don’t injure your eyes. Our daytime star shines about a half million times brighter than the full Moon in visible light and emits potentially harmful ultraviolet (UV) and infrared (IR) radiation too. Looking directly at the Sun through anything that isn’t specially made to deal with all that visible light and invisible radiation is a recipe for serious eye injury, perhaps even blindness. Note that special-purpose solar filters are many thousands of times darker than ordinary sunglasses! What to Look For: How do you know if your eclipse glasses or handheld solar viewers are truly safe? You need to know that they meet the ISO 12312-2 (sometimes written as ISO 12312-2:2015) international safety standard. Filters that are ISO 12312-2 compliant not only reduce visible sunlight to safe and comfortable levels but also block solar UV and IR radiation. Unfortunately, you can’t check whether a filter meets the ISO standard yourself — doing so requires a specialized and expensive piece of laboratory equipment called a spectrophotometer that shines intense UV, visible, and IR light through the filter and measures how much gets through at each wavelength. Solar filter manufacturers send their products to specialized labs that are accredited to perform the tests necessary to verify compliance with the ISO 12312-2 safety specifications. Once they have the paperwork that documents their products as ISO-compliant, they can legitimately use the ISO logo on their products and packaging. Even more unfortunately, unscrupulous vendors can grab the ISO logo off the internet and put it on their products and packaging even if their eclipse glasses or viewers haven’t been properly tested. This means that just seeing the ISO logo or a label claiming ISO 12312-2 certification isn’t good enough. You need to know that the product comes from a reputable manufacturer or one of their authorized dealers. The AAS Solar Eclipse Task Force has been working diligently to compile a list of such vendors, now posted on our Reputable Vendors of Solar Filters & Viewers page. We’ve checked manufacturers’ ISO paperwork to make sure it’s complete and that it comes from a recognized, accredited testing facility, and we’ve personally examined manufacturers’ products. We’ve asked manufacturers to identify their authorized resellers, and we’ve asked dealers to identify the source of the products they’re selling. Only when everything checks out do we add a vendor to our listing. If we don’t list a supplier, that doesn’t mean their products are unsafe — only that we have no knowledge of them or that we haven’t convinced ourselves they are safe. How can you tell if your solar viewer is not safe? You shouldn’t be able to see anything through a safe solar filter except the Sun itself or something comparably bright, such as the Sun reflected in a mirror, a sunglint off shiny metal, the hot filament of an unfrosted incandescent light bulb, a bright halogen light bulb, a bright-white LED flashlight (including the one on your smartphone), or an arc-welder’s torch. All such sources should appear quite dim through a solar viewer. If you can see lights of more ordinary brightness through your eclipse glasses or handheld viewer, and you’re not sure the product came from a reputable vendor, it’s no good. Safe solar filters produce a view of the Sun that is comfortably bright (like the full Moon), in focus, and surrounded by dark sky. If you glance at the Sun through your solar filter and find it uncomfortably bright, out of focus, and/or surrounded by a bright haze, it’s no good. You should contact the seller and demand a refund or credit for return of the product, then obtain a replacement from one of the sources listed on our reputable-vendors page. What if you received eclipse glasses or a handheld solar viewer from a relative, friend, neighbor, or acquaintance? If that person is an amateur or professional astronomer — and astronomers have been handing out eclipse viewers like Halloween candy lately — they’re almost certainly ISO-compliant, because astronomers get their solar filters from sources they know and trust (in other words, from the ones listed on our reputable-vendors page). Ditto for professional astronomical organizations (including college and university physics and astronomy departments) and amateur-astronomy clubs. If you bought or were given eclipse viewers at a science museum or planetarium, or at an astronomy trade show, again you’re almost certainly in possession of ISO-compliant filters. As long as you can trace your filters to a reputable vendor or other reliable source, and as long as they have the ISO logo and a statement attesting to their ISO 12312-2 compliance, you should have nothing to worry about. What you absolutely should not do is search for eclipse glasses on the internet and buy whatever pops up in the ads or search results. Check our list of reputable vendors and buy from one of them. In addition to making sure your eclipse shades or handheld viewers come from a reputable source, make sure they’re in good condition: If the filters are torn, scratched, or punctured, discard them. If the filters are coming loose from their cardboard or plastic frames, discard them. Note: If your eclipse glasses or viewers are compliant with the ISO 12312-2 safety standard adopted in 2015, you may look at the uneclipsed or partially eclipsed Sun through them for as long as you wish. Furthermore, if the filters aren’t scratched, punctured, or torn, you may reuse them indefinitely. Some glasses/viewers — even new ones — are printed with warnings stating that you shouldn’t look through them for more than 3 minutes at a time and that you should discard them if they are more than 3 years old. Such warnings do not apply to eclipse viewers certified to meet the ISO 12312-2:2015 standard and may be ignored. What to Avoid: Ordinary sunglasses (or multiple pairs of sunglasses), neutral density or polarizing filters (such as those made for camera lenses), smoked glass, photographic or X-ray film (unexposed, exposed, or developed), “space blankets,” potato-chip bags, DVDs, and any other materials you may have heard about for solar viewing are not safe. In some cases these homemade filters may seem like they dim the Sun to a comfortable level, but that doesn’t mean they do so across the whole electromagnetic spectrum. While you’re enjoying a “comfortable” view of the “dim” Sun, solar infrared radiation could be cooking your retinas. And you wouldn’t know till later, because your retinas don’t have pain receptors. Only after the eclipse, when you notice blind spots or other vision problems, would you realize you’d made a catastrophic mistake. What about welding filters? The only ones that are safe for direct viewing of the Sun with your eyes are those of Shade 12 or higher. These are much darker than the filters used for most kinds of welding. If you have an old welder’s helmet around the house and are thinking of using it to view the Sun, make sure you know the filter’s shade number. If it’s less than 12 (and it probably is), don’t even think about using it to look at the Sun. Many people find the Sun too bright even in a Shade 12 filter, and some find the Sun too dim in a Shade 14 filter — but Shade 13 filters are uncommon and can be hard to find. Our Reputable Vendors of Solar Filters & Viewers page doesn’t list any suppliers of welder’s filters, only suppliers of special-purpose filters made for viewing the Sun.