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The paper is available (in HTML even) and much better: https://academic.oup.com/astrogeo/article/58/5/5.39/4159289/Solar-eclipse-of-1207-BC-helps-to-date?guestA

by lukasb 9y ago

The paper is available (in HTML even) and much better: https://academic.oup.com/astrogeo/article/58/5/5.39/4159289/Solar-eclipse-of-1207-BC-helps-to-date?guestAccessKey=96454415-36e7-4640-9fde-d942f3ad00b4 https://academic.oup.com/astrogeo/article/58/5/5.39/4159289/...

elliotec 9y ago
Who says they didn’t get eye damage from it? Also, I have a feeling most people I know have looked at the sun unprotected for at least some small period of time (including myself) and our eyes seem ok for now.
- jcims 9y ago
  I used to try to stare at the sun when I was little. It would blot itself out in less than a second with this squishy shimmery black spot (presumably retinal fatigue). It was hard to keep that spot in one place (saccades) though so I would keep chasing it around the sun. Im mildly myopic with astigmatism, but no abnormal blind spots afaik.
  - wnissen 9y ago
    Your brain is really, really good at filling in blind spots. There is a big one where your optic nerve connects to the back of your eye, you can even see it yourself. http://pbskids.org/zoom/activities/sci/blindspot.html http://pbskids.org/zoom/activities/sci/blindspot.html In order to keep from overwhelming the brain with irrelevant optical data, there is a lot of processing going on, and one of the things that happens is a filling in of places where there's no stimulus coming from that part of the eye. It's possible you have blind spots and don't know it. Also, only UV-blocking sunglasses will keep you from getting cataracts.
- canttestthis 9y ago
  Because you didn't look at it during an eclipse, when its more dangerous than looking at it on a regular day.
  - QAPereo 9y ago
    It's only more dangerous because of the potential lack of discomfort/pain and subsequent reflex to look away; in terms of time you can safely spend looking there is no difference.
  - dec0dedab0de 9y ago
    I think it's more dangerous to look at the sun on a regular day, It's just more tempting to look during an eclipse.
  - kobeya 9y ago
    Looking at the Sun for exactly the same period of time is less dangerous during an eclipse because a sizable percentage of the radiation, but not all, is blocked by the Moon. Where the danger comes in is that normally the Sun is so bright that if you mistakenly look into it your natural reflexes cause you to flinch away, prevent anything more than a momentary glimpse lasting fractions of a second. During an eclipse the Sun is dim enough that you could stare at it without "visual pain" (for lack of a better term -- whatever you call something that is too bright) to such a degree as to cause instinctual look-away reflexes. As a result if you were dumb enough, ignorant enough, or presidential enough, you could stare straight at the eclipse for seconds or 10's of seconds during totality. During that time it will not seem "too bright", but nevertheless your eyes will be focusing intensely damaging UV radiation onto your cornea, causing those cells to malfunction and die, which is what causes blindness. That said, this is highly educated, rational crowd. I would not feel comfortable giving this explanation to a gathering of the general public because it can easily be misconstrued to mean "this guy says looking at the Sun during the eclipse is not as dangerous as everyone says it is" which has the exact opposite implication with respect to safety. I expect this is why the "looking at the Sun during an eclipse is more dangerous" meme got started -- it results in better safety.
    - jl6 9y ago
      Why is the light reduced by a huge amount during an eclipse but the UV is still at dangerous levels?
- brudgers 9y ago
  The human visual system has pain receptors that respond when the eye is overexposed to the visible light portion of the electro-magnetic spectrum. It does not have pain receptors for UV and IR radiation. During a solar eclipse the visible spectrum is reduced below the level at which it will cause permanent damage. Near IR and UV are not, so it is easier to damage one's eyes without experiencing pain.

by lukasb 9y ago

elliotec 9y ago

Who says they didn’t get eye damage from it? Also, I have a feeling most people I know have looked at the sun unprotected for at least some small period of time (including myself) and our eyes seem ok for now.

jcims 9y ago
I used to try to stare at the sun when I was little. It would blot itself out in less than a second with this squishy shimmery black spot (presumably retinal fatigue). It was hard to keep that spot in one place (saccades) though so I would keep chasing it around the sun. Im mildly myopic with astigmatism, but no abnormal blind spots afaik.
- wnissen 9y ago
  Your brain is really, really good at filling in blind spots. There is a big one where your optic nerve connects to the back of your eye, you can even see it yourself. http://pbskids.org/zoom/activities/sci/blindspot.html http://pbskids.org/zoom/activities/sci/blindspot.html In order to keep from overwhelming the brain with irrelevant optical data, there is a lot of processing going on, and one of the things that happens is a filling in of places where there's no stimulus coming from that part of the eye. It's possible you have blind spots and don't know it. Also, only UV-blocking sunglasses will keep you from getting cataracts.
canttestthis 9y ago
Because you didn't look at it during an eclipse, when its more dangerous than looking at it on a regular day.
- QAPereo 9y ago
  It's only more dangerous because of the potential lack of discomfort/pain and subsequent reflex to look away; in terms of time you can safely spend looking there is no difference.
- dec0dedab0de 9y ago
  I think it's more dangerous to look at the sun on a regular day, It's just more tempting to look during an eclipse.
- kobeya 9y ago
  Looking at the Sun for exactly the same period of time is less dangerous during an eclipse because a sizable percentage of the radiation, but not all, is blocked by the Moon. Where the danger comes in is that normally the Sun is so bright that if you mistakenly look into it your natural reflexes cause you to flinch away, prevent anything more than a momentary glimpse lasting fractions of a second. During an eclipse the Sun is dim enough that you could stare at it without "visual pain" (for lack of a better term -- whatever you call something that is too bright) to such a degree as to cause instinctual look-away reflexes. As a result if you were dumb enough, ignorant enough, or presidential enough, you could stare straight at the eclipse for seconds or 10's of seconds during totality. During that time it will not seem "too bright", but nevertheless your eyes will be focusing intensely damaging UV radiation onto your cornea, causing those cells to malfunction and die, which is what causes blindness. That said, this is highly educated, rational crowd. I would not feel comfortable giving this explanation to a gathering of the general public because it can easily be misconstrued to mean "this guy says looking at the Sun during the eclipse is not as dangerous as everyone says it is" which has the exact opposite implication with respect to safety. I expect this is why the "looking at the Sun during an eclipse is more dangerous" meme got started -- it results in better safety.
  - jl6 9y ago
    Why is the light reduced by a huge amount during an eclipse but the UV is still at dangerous levels?
brudgers 9y ago
The human visual system has pain receptors that respond when the eye is overexposed to the visible light portion of the electro-magnetic spectrum. It does not have pain receptors for UV and IR radiation. During a solar eclipse the visible spectrum is reduced below the level at which it will cause permanent damage. Near IR and UV are not, so it is easier to damage one's eyes without experiencing pain.