The spectacular phenomenon of a solar eclipse presents a severe risk to eye health, demanding specialized protection for safe viewing. Looking directly at the sun, even when it is partially obscured, can cause permanent retinal damage in seconds, a condition known as solar retinopathy. Certified solar viewing glasses are the only means to protect your eyes and safely observe the event, as the sun’s surface remains incredibly bright. Finding these glasses requires knowing where to look and how to verify their authenticity to ensure they provide the necessary defense against intense solar radiation.
Identifying Safe Viewing Protection
Genuine solar viewing glasses must meet the international safety standard ISO 12312-2:2015 to ensure they block the required amount of light. This standard mandates that the lenses filter out 100% of harmful ultraviolet (UV) and infrared (IR) light, as well as 99.999% of intense visible light.
You should only purchase glasses that have the manufacturer’s name and contact information printed on the product, which is an ISO requirement. Inspect the lenses before use; any scratches, punctures, or tears compromise the filter’s integrity and render the glasses unsafe. Counterfeit glasses are common, often flooding online marketplaces with fake “ISO certified” claims, so verifying the vendor’s reputation is important.
Retail and Commercial Sources
The most reliable commercial sources for purchasing safe solar viewers are vendors endorsed by the American Astronomical Society (AAS). The AAS maintains a list of manufacturers and authorized dealers who comply with the ISO 12312-2 standard. Buying directly from a company on this list significantly reduces the risk of acquiring counterfeit products.
Certified glasses are often sold through specialized camera shops, telescope retailers, and the online stores of reputable astronomy organizations. Because demand is extremely high leading up to an eclipse, securing certified glasses well in advance is recommended, and it is advised to only buy from a seller specifically named on the AAS list to ensure authenticity.
Community and Institutional Distribution
Many public organizations and local institutions organize distribution programs to provide free solar eclipse glasses. Public libraries nationwide are a common resource, frequently participating in programs that distribute millions of ISO-compliant glasses, often supported by science-focused initiatives.
Science museums, planetariums, and local astronomy clubs are also excellent sources for obtaining viewers. These locations frequently host viewing events and educational programming, including the distribution of certified glasses. Since supplies are typically limited, it is advisable to check the specific website or call ahead to confirm availability and distribution schedules.
Safe Viewing Alternatives
If you are unable to find certified glasses, indirect viewing methods offer a safe way to experience the eclipse. The most accessible method is creating a pinhole projector, which involves allowing sunlight to pass through a small hole onto a surface behind it. This projects a small, inverted image of the sun that you can safely watch.
A simple pinhole can be made using card stock or a cereal box with a small opening punched into aluminum foil. You must stand with your back to the sun and view the projected image on the ground or screen, never looking through the hole itself. Another option is using a welder’s filter, but only one with a Shade 14 rating provides adequate protection; lower shade number filters are not safe for solar viewing.