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Re:Sunlight through glass does not provide Vitamin D by Bartweiss on Monday February 25, 2019 @11:12AM (#19246610)
I've never really understood this story. Feynman wasn't wrong, but UV-A and even sufficiently-bright visible light also cause eye damage.

Did he know the main visual hazard from the bomb was UV-B? Did he just get lucky?

Re:Sunlight through glass does not provide Vitamin D by StrictDabbler on Monday February 25, 2019 @12:38PM (#19247498)
We don't even know that he got lucky.

Lasers didn't exist yet to force us to study retinal exposure to bright non-UV light and the flash from the bomb didn't last that long, nor were the first few bombs that bright, so he may have been fine... but obviously if you stare at the sun through three inches of glass you're still going to burn your retinas.

He says "I figured the only thing that could really hurt your eyes (bright light can never hurt your eyes) is ultraviolet light. I got behind a truck windshield, because the ultraviolet can’t go through glass, so that would be safe, and so I could see the damn thing."

What we know from later laser research is that unless you have a comprehensive visual field test, it's often hard to identify that part of your retina has been scorched. Your brain just filters it out as a blind-spot and you don't realize what you're failing to see.

There's every chance that Feynman totally burned a section of his retina and never realized it, and there's every chance that he was fine because the exposure at his distance wasn't that bad, but at the end of the day he was more reckless than insightful in this situation.

Re:Sunlight through glass does not provide Vitamin D by kragen on Monday February 25, 2019 @01:17PM (#19247919)
Maybe he should have closed one eye, but the first atomic bomb only explodes once. Your body won't last forever no matter how well you care for it (as Feynman well knew, having just watched his wife Arline die slowly of incurable tuberculosis); seeing the first atomic-bomb test with your own eyes seems eminently worth the risk of blindness, or even sacrificing an eye.
Re:Sunlight through glass does not provide Vitamin D by abdulhaq on Monday February 25, 2019 @01:32PM (#19248066)
I really can't agree. I would not exchange my eyesight for the whole world, literally. Therefore the qudos of having looked at a novel explosion in no way compensates for any risk to my eyes.
Re:Sunlight through glass does not provide Vitamin D by blotter_paper on Monday February 25, 2019 @02:44PM (#19248703)
>I would not exchange my eyesight for the whole world, literally.

FYI vacuum exposure can cause blindness, visual impairment, and death.

[dead]
Re:Sunlight through glass does not provide Vitamin D by muraiki on Monday February 25, 2019 @05:38PM (#19250163)
Downvoted not because I’m afraid of my own mortality, but because pointing out the obvious fact that nobody can see after they die is neither insightful nor useful. Go tell that to someone who has become blind and let me know how much consolation that provides them.
Re:Sunlight through glass does not provide Vitamin D by abdulhaq on Monday February 25, 2019 @03:17PM (#19249023)
Even if I knew was going to die tomorrow, I will not exchange my remaining eyesight for qudos. I would prefer to spend my last day looking at my family, the trees, the running water, the flowers. It seems totally uncontroversial to me, I'm really surprised to find someone who disagrees.
Re:Sunlight through glass does not provide Vitamin D by bryanrasmussen on Monday February 25, 2019 @02:47PM (#19248735)
I thought the next few decaces was a climate change reference.
Re:Sunlight through glass does not provide Vitamin D by kragen on Monday February 25, 2019 @02:55PM (#19248810)
Sorry, no, I just meant that the maximum human lifespan recorded so far is 12.2 decades, and the vast majority of people reading this will die in even less, 2–5 decades, regardless of what happens with climate change. Given that, it's silly to treat your body as if you could make it last forever.

I've edited my comment above to clarify.

Re:Sunlight through glass does not provide Vitamin D by pshc on Monday February 25, 2019 @03:35PM (#19249201)
I think people understand the nihilistic viewpoint but it makes no sense to sacrifice your health while you still have it.
Re:Sunlight through glass does not provide Vitamin D by Florin_Andrei on Monday February 25, 2019 @03:10PM (#19248951)
> bright light can never hurt your eyes

Before y'all criticize that statement, keep in mind it's coming from one of the best scientists of the 20th century.

He was talking before lasers. For a purely thermal source to hurt the eyes, it would have to be:

1. insanely hot

2. quite close to the observer

First condition is met by the nuke, but the second one, obviously, is not, unless you're a victim of the explosion.

Re:Sunlight through glass does not provide Vitamin D by ISL on Monday February 25, 2019 @06:35PM (#19250551)
Scientists, even the best ones, do dumb things all the time.

Source: Am experimental physicist; do dumb things. Sometimes my colleagues do too, even the best ones.

Re:Sunlight through glass does not provide Vitamin D by justin66 on Monday February 25, 2019 @07:34PM (#19250957)
Los Alamos was replete with brilliant people doing dangerously stupid things.

https://en.wikipedia.org/wiki/Demon_core

Re:Sunlight through glass does not provide Vitamin D by Florin_Andrei on Tuesday February 26, 2019 @03:44PM (#19258142)
I know. It was not meant as an absolute statement.
Re:Sunlight through glass does not provide Vitamin D by astrodust on Monday February 25, 2019 @08:14PM (#19251194)
As much as a window blocks UV, I wouldn't trust a laser if a high-powered UV laser was aimed through it at my eye.
Re:Sunlight through glass does not provide Vitamin D by failrate on Monday February 25, 2019 @05:46PM (#19250216)
I have a scar on my retina near the fovea, and I can only see it if I deliberately focus on it.
Re:Sunlight through glass does not provide Vitamin D by hinkley on Monday February 25, 2019 @03:41PM (#19249253)
Are we sure he wasn’t wearing sunglasses too?
Re:Sunlight through glass does not provide Vitamin D by Spellchamp on Monday February 25, 2019 @11:58AM (#19247032)
Yep, he basically says that he knew the only thing that would damage his eyes would be UV-B, so he just went for it. Long time since I read the book but that's what I remember.