We've been hearing a lot of reports lately of fake solar eclipse glasses. In Greenville, many vendors are completely sold out. Kidding Around Greenville has the most up-to-date list, which is updated daily. But, those who have ordered online or from a third-party retailer, should check the validity of their glasses.

According to the American Astronomical Society, safe glasses will block everything from your vision other than the sun, and need to comply with ISO 12312-2. They've worked to put together a list of safe vendors + national companies that have been selling from safe vendors. (Roper Mountain Science Center, GHS Eye Institute glasses are reputable, as are most ones from 7-11, Walmart, and other stores according to the list from AAS.)

Even Amazon went on a customer service rampage, letting their customers know that the glasses they purchased from third party sellers may not be certified. Turns out, the ISO number may not be the glasses saving grace.

So how do you tell the real from the fake?

Round, ball-like ends: The fake glasses will have more rounded, ball-like ends that wrap around your ears as shown in the image below.

2. Boxy, less- rounded lenses: The fake glasses will have lenses that look more square around the edges, rather than rounded.

Make sure you check the glasses you have for these two subtle differences to ensure you're being as safe as possible during the upcoming eclipse.

Why? You can majorly damage your corneas by looking at the sun. As a note: When the sun is in full totality (it's dark), you can take off the glasses. But in partial totality, keep them on.

If you can't find glasses, you can still enjoy the eclipse! Science Friday explains how to create a sun projector, so you can watch how light disappears during the total eclipse, without looking directly at the sun.