BALTIMORE (WJZ) — As millions of people wait to watch history on August 21, the solar eclipse has created big business opportunities, especially for protective eye wear.

But beware, there are plenty of people looking to make a quick buck by selling fake glasses.

The problem with these scams, is that they can cause serious eye problems for those viewing the eclipse.

NASA and the American Astronomical Society are aware of the fakes populating the glasses market and are doing their best to thwart scams.

“Everything was going along fine until the public started to wake up to the eclipse and started buying things that may or may not be safe,” said Rick Fienberg, an astronomer and press officer at the American Astronomical Society, via Quartz. “Now they are peppering us and NASA with questions.”

“Now they are peppering us and NASA with questions.”

Meanwhile, there are legitimate sellers on the market, who have been approved and are selling safe, helpful products.

“It’s all nonsense,” said Mark Margolis, of NASA-approved Rainbow Symphony.

“There are a zillion companies putting out the same product and they all have different names. And this isn’t because I don’t want competition in the marketplace. We’re oversold and on back-order. It’s not my motive to keep competitors out of the market.”

If you still need to buy yours, here are the five companies NASA recommends:

The eclipse will be visible from most places in America, but only a limited portion of the country will experience the total eclipse.

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