Has there ever been any evidence that would suggest long-term damage from looking directly into the sun?

Question

If so what? If not why do the always tell you that you shouldn't?

Answer 1

UM........BLINDNESS?

Answer 2

Blindness is often reported in sailors who used sextants and similar instruments that had to take frequent readings of the sun's angle:

http://www.pbs.org/wgbh/nova/longitude/secrets.html

If you haven't noticed.. looking into the sun for even a few seconds will bleach out parts of your retina severely. You can see the effect by "looking at the afterimage": turn away from the sun and look at a white paper. Can you see the dark/colored dots and lines? Those are caused by the light from the sun desensitizing your retina cells. Now, what do you think will happen if you keep looking at the sun for a few minutes instead of a few seconds, thus increasing the bleaching effect a hundredfold and probably the temperature rise in the retina severalfold?

Most people do not realize how much more flux there is in direct than in reflected sunlight. The sun has an angular diameter of half a degree. Thus the image on the retina will also have such an angular size. Here is an explanation:

http://fer3.com/arc/m2.aspx?i=015856&y=200405

If you compare that to diffused reflected light, which will fill all of the retina (which has a 120 degree field of view), the effective amount of light hitting that one spot will be intensified by many hundredfold. The human eye, of course, is evolved to
look at diffusely reflected light, there is no survival advantage in looking at the sun directly. Therefor nature has adjusted the sensitivity thresholds to seeing in the dark and during normal daylight conditions. The dynamic range of that is already enormous, but the last three to four orders of magnitude or so of looking at the sun directly have not been designed in by evolution.

But since I sense a defiant soul in you which wants to break the rules for breaking the rules sake, just go ahead. The eye doctor will diagnose and treat your burned retina as well as he can and once you are half blind, you will probably take a more cautious attitude towards well meant warnings.

Answer 3

This condition is known as solar retinopathy. It has been known for 1000's of years. Modern medical studies date back to 1860's. The first link below is a nice summary of the previous studies.

It's one thing to look at the sun for a few seconds. You only destroy the light-sensitive chemicals in your eye. After a few hours or maybe a day, your body will make some more.

But if you look at the sun for more than 10 seconds or so, the damage will be long-term. If you are lucky, you will be blind for only a few months or a year or so. There have been many report of permanent blindness.

Answer 4

Yes - looking directly at the sun for even a few seconds can cause serious eye damage. Blindness can result in less than 20 seconds of unprotected viewing of the sun.

Dozens of astronomers over the decades and centuries have been blinded (either right away of after some time of deteriorating vision) from solar observations.

Answer 5

Yes, there has been evidence. Do not try this. There have been many different ways to experiment this...first, they use animals to test. They lock their head into a position that stares directly into the sun. Within 10 minutes later, the animal is blind. The second proven evidence. Have you ever tried using a mygnifying glass to burn ants? You know it works, right? Well, your eyes are like magnifying lenses, they stare directly into the sun and burn your pupils and your eyes are damaged. DO NOT TRY THIS

Answer 6

I don't know about you, but I find looking directly at the Sun even for a fraction of a second to be extremely painful, so I couldn't look at if directly even if I tried. Anything that painful HAS to be damaging.

Answer 7

You can test this without looking into the sun - take a small magifying glass and focus the light from the sun (use one about 2 cm in diameter) - focus on a piece of paper (black print works quicker) - it will at least char the paper if not start it on fire. now your retina is the piece of paper - it can be permanently damaged by the sun focused on it for any appreciable time. (i.e. seconds)...

Answer 8

well if you just glance at it the image is burned into your retina for a little while. if you look at the sun for a long time it WILL cause severe damage to your eyes. staring at it for too long will permanently burn your retina and could cause you to go blind.

Answer 9

I even have regarded at solar many situations. yet i could not see sunspots. After observing solar everywhere i seem I in basic terms see yellow patches/ In night or at sunrise, the solar is alluring and relaxing to observe.

Answer 10

I haven't seen any scientific evidence but I believe it for sure!