One of the most-discussed points of viewing a solar eclipse is that it should never be done without proper protection. The reason for this isn’t because the sun’s rays are particularly dangerous or powerful during a solar eclipse – it’s just that most people wouldn’t think of staring at the sun unless it’s a solar eclipse, precisely for the reason that it’s such a rare event.

The Science of Light
Think about this. Have you ever tried burning grass or a piece of paper with a lens on a cloudless day? It’s entirely possible – in fact, it’s quite easy. Now, consider this – your eyes have a lens. Staring at the sun concentrates its light through your eyes to the back of your eyes, near the nerves – there, the eye has light-sensitive cells that are so complex and powerful that they can perceive the tiniest fraction of light in pitch darkness and use it to see the reflections on all objects around us – in total darkness, the stars in the sky are all we need to safely move about at night without stumbling over every rock and branch.

When you’re staring at the strongest, most powerful source of light known to man in the solar system, you’re effectively charring these cells.

Real-Life Cases
Your body knows how to repair them, but the damage lasts for a long time. As an example, a UK study once looked into patients suffering what’s called solar retinopathy – that’s a condition characterized by signs of retinal damage caused directly by sunlight – following the famous 1999 total solar eclipse. One subject was a seventeen year old girl who was high on “speed” – presumably an amphetamine – and as a result, she stared at the solar eclipse for roughly half an hour.

Her vision was worsened considerably, and she had symptoms of blind spots and holes in her vision for several months. Eventually, she did recover enough to retain 6/6 vision (that is, normal vision) – but the other members of the study proved that even just a glimpse of the sun during a solar eclipse could impair your vision for days, or weeks.

It’s different when your exposure to such levels of light are constant, and frequent; your eyes eventually develop cataracts, and you would go blind with time.

To avoid permanent – or even partial damage to your eyes, remember to wear sunglasses on a sunny day – and more importantly, don’t view a solar eclipse without the proper eclipse eye protection, such as glasses by Eclipse Glasses.