3 ms·

Thanks for elaborating! I remembered hearing something to that extent back in 2017, but after I couldn't find any primary sources on it online, I'd dismissed it

Thanks for elaborating! I remembered hearing something to that extent back in 2017, but after I couldn't find any primary sources on it online, I'd dismissed it as a rumor. Absolute duration would still be the primary factor, in any case. Luckily I've never had any eye problems myself, but not for lack of trying. Back in elementary school, I would occasionally stare at the outdoor sun for 30 seconds or longer, just to see what could possibly be so bad about it. Yet my eyes remain undamaged, at least as far as any optometrist has told me. Hence why I was skeptical about the supposed danger of eclipses. But perhaps the interval before damage can be much shorter, depending on age and other factors.

schoen 2y ago
I think there are probably factors like * latitude * time of day¹ * individual genetics (maybe including something about the anatomy of your iris? or the focal abilities of your eye?) * how fixedly you manage to stare at the sun, as opposed to letting your eye wander around a bit * how frequently you unconsciously blink that would cause the degree of injury to vary a lot. But it's understandable that experts would like to emphasize the really, just don't stare at the sun principle as the most reliable advice, so people don't do a lot of second-guessing (like "oh well I'm at a high latitude so it's not that bad"). I had also stared at the sun a little bit on occasion in elementary school (but for like 4-5 seconds, not like 30 seconds!) and that was one thing that gave me some counterproductive confidence that it wouldn't be super-harmful super-quickly. ¹ Notably, a lot of people will "watch the sunset" for like 1-5 minutes at a time, which is a form of starting at the sun, and I've never heard of that causing anyone any trouble. It really is true that time of day and latitude both have a big effect on the intensity of sunlight. Among other things, this interactive diagram makes pretty clear why watching the moment of sunset isn't that dangerous: https://engaging-data.com/solar-intensity/ https://engaging-data.com/solar-intensity/ It's easy to confirm there that the incident power in direct sunlight can vary by a factor of 100× as you get further from the tropics and closer to the moment of sunrise or sunset. But it's not a great risk to have lots of people apply these heuristics to justify staring at the sun. If you just get a little bit confused about the details, the potential for damage is very, very high!
- LegionMammal978 2y ago
  As I like to say, it's funny that humans are the one and only member of the animal kingom who must be told not to stare at the sun.

schoen 2y ago

I think there are probably factors like * latitude * time of day¹ * individual genetics (maybe including something about the anatomy of your iris? or the focal abilities of your eye?) * how fixedly you manage to stare at the sun, as opposed to letting your eye wander around a bit * how frequently you unconsciously blink that would cause the degree of injury to vary a lot. But it's understandable that experts would like to emphasize the really, just don't stare at the sun principle as the most reliable advice, so people don't do a lot of second-guessing (like "oh well I'm at a high latitude so it's not that bad"). I had also stared at the sun a little bit on occasion in elementary school (but for like 4-5 seconds, not like 30 seconds!) and that was one thing that gave me some counterproductive confidence that it wouldn't be super-harmful super-quickly. ¹ Notably, a lot of people will "watch the sunset" for like 1-5 minutes at a time, which is a form of starting at the sun, and I've never heard of that causing anyone any trouble. It really is true that time of day and latitude both have a big effect on the intensity of sunlight. Among other things, this interactive diagram makes pretty clear why watching the moment of sunset isn't that dangerous: https://engaging-data.com/solar-intensity/ https://engaging-data.com/solar-intensity/ It's easy to confirm there that the incident power in direct sunlight can vary by a factor of 100× as you get further from the tropics and closer to the moment of sunrise or sunset. But it's not a great risk to have lots of people apply these heuristics to justify staring at the sun. If you just get a little bit confused about the details, the potential for damage is very, very high!

LegionMammal978 2y ago
As I like to say, it's funny that humans are the one and only member of the animal kingom who must be told not to stare at the sun.