The only time it's really safe to look at the sun directly is during a solar eclipse, when the corona appears.
Solar eclipse of November 13, 2012
As soon as you get even the diamond ring effect you should look away.
It's not guaranteed that you'd lose your sight or anything like that. But you don't feel anything at the time. A quick glance at the sun doesn't make you go blind.
What happens if you stare at the sun is that it damages the center of your retina. If you look at it through a telescope, your eye can quite literally burn from the heat, and you won't feel anything because there are no pain receptors.
But if you look without any optical instrument the main danger is from ultra violet rather than infra red. You feel nothing at the time, and later on you'll notice a dark patch in your vision. Sir Isaac Newton did this deliberately - stared at the sun to create after image effects to observe them. He had problems with his sight for some months afterwards. His eyes did recover eventually. Often people will share stories of staring at the sun as a child and say their eyes are still okay. But you might not be so lucky.
You'd get a dark spot in the center of your eye - a permanent one if you get permanent damage. And we need that part of our eye for all the detailed work we do e.g. reading, also for most of our colour recognition. Not a nice thing to happen to you. You might not be able to read any more for instance.
It might seem safe to look at the sun through clouds when it is much less bright visually. But you don't know how much UV light is transmitted through the clouds so it might be just as dangerous.
It's less dangerous at the moment of sunrise and sunset - which is why many people do spend a lot of time looking at a setting sun or rising sun without damage. But that's also because they aren't staring at the sun only but moving their eyes around looking here and there. I wouldn't stare directly at the sun for any length of time with it just in one spot in my field of view, even at sunrise or sunset.
Some of those who do sun gazing say they do it only at sunrise and sunset - less dangerous but if you care about your vision, still I wouldn't do that either or with a great deal of caution, like look for a few seconds, then longer periods and carefully monitor the effects on your eyes getting medical advice about how to do that.
But the safest thing is just to get eclipse glasses. You won't see anything except the sun itself, as a yellow or orange disk but you can look directly at the sun for a while without any risk of damaging your eyes - so long as they aren't damaged in any way, e.g. no scratches. If you want to take up this ancient practice of sun gazing (well supposedly anyway) I think you could do it safely with eclipse glasses, and so long as you don't do it for long periods - even those I'm not sure about steadily staring at the sun for like hours or some such. But if it was like a minute or two every day or some such. After all you are still looking directly at the sun, if filtered admittedly. So if you think that direct light from the sun into your eyes has health benefits, well that's exactly what you have there.
I'm not sure why sun gazers didn't go blind, or maybe they did. The claim that some some yogis safely stare at the midday sun for hours on end is a bit like the claim that some yogis can levitate - if it is possible at all it would seem to be in some way not be subject to the laws of physics and biology as we know them. I keep an open mind about whether that is possible, it might be that our mind can do more than we think it can - but whether or not - I wouldn't count on being able to do that any more than you'd jump off a cliff and hope you would levitate :). Because for sure, some people have lost their vision in this way, either temporarily like Newton for a few months, or permanent damage sometimes.
I'm answering this as a question about the practice of sun gazing, supposed medical benefits from staring at the sun. Not about sun observation - if you want to observe the sun, e.g. to look for sun spots or flares etc, you can use projection methods, or use a filter at the OBJECTIVE END of the telescope or get a dedicated solar scope, or for that matter just visit the SOHO website for live images of the sun. And you'll get much better views that way also.
Except of course during solar eclipse when you can look directly at the corona indeed you absolutely should, it's the best part (so I'm told, never seen one myself) and you won't see a thing through filters - and you can observe it with binoculars and telescopes also so long as you go back to indirect or filtered viewing at the moment of the diamond ring effect.
The Very Latest SOHO Images
As soon as you get even the diamond ring effect you should look away.
It's not guaranteed that you'd lose your sight or anything like that. But you don't feel anything at the time. A quick glance at the sun doesn't make you go blind.
What happens if you stare at the sun is that it damages the center of your retina. If you look at it through a telescope, your eye can quite literally burn from the heat, and you won't feel anything because there are no pain receptors.
But if you look without any optical instrument the main danger is from ultra violet rather than infra red. You feel nothing at the time, and later on you'll notice a dark patch in your vision. Sir Isaac Newton did this deliberately - stared at the sun to create after image effects to observe them. He had problems with his sight for some months afterwards. His eyes did recover eventually. Often people will share stories of staring at the sun as a child and say their eyes are still okay. But you might not be so lucky.
You'd get a dark spot in the center of your eye - a permanent one if you get permanent damage. And we need that part of our eye for all the detailed work we do e.g. reading, also for most of our colour recognition. Not a nice thing to happen to you. You might not be able to read any more for instance.
It might seem safe to look at the sun through clouds when it is much less bright visually. But you don't know how much UV light is transmitted through the clouds so it might be just as dangerous.
It's less dangerous at the moment of sunrise and sunset - which is why many people do spend a lot of time looking at a setting sun or rising sun without damage. But that's also because they aren't staring at the sun only but moving their eyes around looking here and there. I wouldn't stare directly at the sun for any length of time with it just in one spot in my field of view, even at sunrise or sunset.
Some of those who do sun gazing say they do it only at sunrise and sunset - less dangerous but if you care about your vision, still I wouldn't do that either or with a great deal of caution, like look for a few seconds, then longer periods and carefully monitor the effects on your eyes getting medical advice about how to do that.
But the safest thing is just to get eclipse glasses. You won't see anything except the sun itself, as a yellow or orange disk but you can look directly at the sun for a while without any risk of damaging your eyes - so long as they aren't damaged in any way, e.g. no scratches. If you want to take up this ancient practice of sun gazing (well supposedly anyway) I think you could do it safely with eclipse glasses, and so long as you don't do it for long periods - even those I'm not sure about steadily staring at the sun for like hours or some such. But if it was like a minute or two every day or some such. After all you are still looking directly at the sun, if filtered admittedly. So if you think that direct light from the sun into your eyes has health benefits, well that's exactly what you have there.
I'm not sure why sun gazers didn't go blind, or maybe they did. The claim that some some yogis safely stare at the midday sun for hours on end is a bit like the claim that some yogis can levitate - if it is possible at all it would seem to be in some way not be subject to the laws of physics and biology as we know them. I keep an open mind about whether that is possible, it might be that our mind can do more than we think it can - but whether or not - I wouldn't count on being able to do that any more than you'd jump off a cliff and hope you would levitate :). Because for sure, some people have lost their vision in this way, either temporarily like Newton for a few months, or permanent damage sometimes.
I'm answering this as a question about the practice of sun gazing, supposed medical benefits from staring at the sun. Not about sun observation - if you want to observe the sun, e.g. to look for sun spots or flares etc, you can use projection methods, or use a filter at the OBJECTIVE END of the telescope or get a dedicated solar scope, or for that matter just visit the SOHO website for live images of the sun. And you'll get much better views that way also.
Except of course during solar eclipse when you can look directly at the corona indeed you absolutely should, it's the best part (so I'm told, never seen one myself) and you won't see a thing through filters - and you can observe it with binoculars and telescopes also so long as you go back to indirect or filtered viewing at the moment of the diamond ring effect.
The Very Latest SOHO Images
About the Author
Robert Walker
Writer of articles on Mars and Space issues - Software Developer of Tune Smithy, Bounce Metronome etc.Studied at Wolfson College, Oxford
Lives in Isle of Mull
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