ENES

Eclipse Glasses: How to Watch Safely

Looking at the Sun without proper protection can injure your eyes, and an eclipse tempts people to stare for a long time. This page follows NASA and American Astronomical Society (AAS) guidance. It is not a shop.

Safe viewing in 3 steps

  1. Use certified eclipse glasses for every partial phase.
  2. Check them for scratches or tears first; supervise children.
  3. Take them off only during totality, and put them back on at once.
Safety checklist

What the 12312-2 standard means, in plain words

12312-2 is an international standard for filters you look at the Sun through with your own eyes. Glasses that meet it block almost all of the Sun's light, including the invisible kinds that can hurt your eyes without you feeling it. NASA describes safe solar viewers as thousands of times darker than sunglasses. In short: if a pair of eclipse glasses truly meets the 12312-2 standard, it is dark enough to look at the bright Sun.

The catch is that anyone can print the standard’s number on a box. The AAS therefore advises buying from known manufacturers or the dealers those manufacturers publicly name, and not from random online ads. The AAS keeps a list of manufacturers whose products it is satisfied meet the standard. In Spain, the OVAE volunteer group runs a similar list called Eclipse Seguro.

Where to check a brand

We do not sell glasses, name brands or link to shops.

Before you use them

  • Regular sunglasses, however dark, are not safe.
  • Inspect your glasses. If they are torn, scratched or damaged, throw them away (NASA).
  • Always supervise children.
  • Never look through a camera, binoculars or telescope while wearing eclipse glasses. The focused light burns through the filter. Those devices need their own solar filter, fixed to the front.

When you can take them off

During a total eclipse, NASA says you may look without protection only during totality, when the Moon fully covers the Sun's bright face. You will know it is safe when you can no longer see any part of the Sun through your glasses. As soon as any bright Sun reappears, put them straight back on.

In Seville or Aswan, which see only a partial eclipse, there is no safe moment without glasses.

No glasses? Use a pinhole

Punch a small hole in a card, stand with the Sun behind you and let the light fall on paper. You will see a small crescent Sun. A kitchen colander does the same. Never look at the Sun through the hole.

FAQ

Are my glasses from a past eclipse still OK?

If they meet the 12312-2 standard and are undamaged, NASA's inspection rule applies: check for scratches or tears.

Can I photograph the eclipse with my phone?

Only with a proper solar filter over the lens during the partial phases. Remove it during totality.

Do I need sunscreen?

Yes. You may be in direct sun for hours, so NASA recommends sunscreen, a hat and protective clothing.