APOD: Sunspot Castle (2011 Nov 12)

[TNT]

Wow! What a striking image! Who knew sunspots could be seen with the unaided eye?

[Randy Shivak]

Huge Solar Prominence Today!

[Randy Shivak]

On the other side of the sun was this group of prominences.

[zloq]

Not a handy one. But I've read several peer reviewed papers on the subject, with a rigorous analysis of the optical characteristics of lens materials and pupil response, and supported by statistical information regarding cataract rates and age of onset. Those papers would have been published in the early 1990s.

Well - if you find a pointer to any such papers - that would be great. I'm aware of epidemiological studies in the 90's - but at that point they were having enough trouble just demonstrating that cataracts are definitively linked to UV exposure at all - let alone the much more subtle issue that sunglasses might have caused more than would have appeared otherwise. This is a topic I have been interested in over the years, and I lean much farther the other way - that UV protection from typical sunglasses today is much more effective than commonly thought - just based on the materials - and I doubt the claim that early sunglasses made things worse for those who wore them.

Here is the abstract of a 2002 review of studies that concludes - yes - cataracts are linked to UV exposure and it is pretty well accepted:

http://www.ncbi.nlm.nih.gov/pubmed/12061276

That indicates how difficult, and recent, just proving the connection between cataracts and UV has been - with so many human and environmental factors.

For the issue of sunglasses, uv, and pupil dilation, there is an older paper in Appl. Optics by Hoover, 26, 4, 689, 1987. The first line of the abstract says,

"The supposition that, because of pupil dilation, there are greater influxes of solar UV and short-wavelength visible radiation when some sunglasses are worn is wrong. It is based on an incomplete and, therefore, misleading analysis."

He has a detailed analysis showing, as I suggested, that you need to look at the trade off between reduced exposure and increased pupil size - and you need to consider the overall reduction of the full UV spectrum - since even glasses that let some longer wave UV through will be very effective at reducing the shorter and most damaging wavelengths that would otherwise be roaring in. Although the paper is older, he did a study of sunglass materials up to his time - so he was looking at the right materials rather than more modern ones that have additives to block UV.

So - let's just say this is something I disagree with you about - and I see it written all the time. To me it has a common sense, "Sounds good - must be true" feel to it - but when I thought about it over the years, it never made sense to me. I don't need to belabor it since I know many people on the web say the same thing you do. I am just looking for journal papers - especially epidemiological studies - that conclude there has been an increase in cataracts lately linked to early inferior sunglass use.

zloq

[Chris Peterson]

The earliest records are from the Bible, as well as early Hindu records. Early cataract surgery was developed by the Indian surgeon, Sushruta (6th century BCE). The Indian tradition of cataract surgery was performed with a special tool called the jabamukhi salaka, a curved needle used to loosen the lens and push the cataract out of the field of vision.

The procedure is called couching, and was probably used by the ancient Egyptians, and perhaps even earlier. I own a fine Arabic bronze couching needle, probably made (and used) in 11th century Damascus. This is not the sort of needle I'm comfortable seeing plunged into an eye- especially not my own!

[Beyond]

The earliest records are from the Bible, as well as early Hindu records.

Records pertaining to what? Cataracts, surgery, or both? And where abouts is it located in the Bible?? I don't ever remember running across any eye surgery. Although Sodom could have received a mass case of severe cataracts just before it got burned up.

[neufer]

"In the land of the blind,
the one-eyed man is king."
- Erasmus's Adagia (1500)

The earliest records are from the Bible,

Records pertaining to what?

Cataracts. Here, let me lead you by the hand:

"Let their eyes be darkened, that they see not;" -- Psalm 69:23

"And immediately there fell on him a mist and a darkness;
and he went about seeking some to lead him by the hand." -- Acts 13:11

[Beyond]

"In the land of the blind,
the one-eyed man is king."
- Erasmus's Adagia (1500)

The earliest records are from the Bible,

Records pertaining to what?

Cataracts. Here, let me lead you by the hand:

"Let their eyes be darkened, that they see not;" -- Psalm 69:23

"And immediately there fell on him a mist and a darkness;
and he went about seeking some to lead him by the hand." -- Acts 13:11

Aw, c'mon neuf, the context of Psalm 69:23 is about people not understanding Jesus because He's been 'hidden' from their view. It's not a physical eyesight thingy.
Acts 13:11 has a bit more possibility, However, there is a mist and a darkness involved. It's not said whether or not others around when the sorcerer was 'blinded' saw the mist and darkness or not. It was said that he would be blind and not see the sun for a while. I take that to be more like the plague in Egypt, when the land where the Hebrews were had sunlight, but the Egyptians were all in darkness for a while.
Even Paul himself was blind for a time when he was still called saul. But his blindness was because of something like scales over his eyes.
So you're going to have to do a bit better neuf, if you want to link cataracts to Bible blindness. Maybe you'd better do a lot more reading.

[Chris Peterson]

Aw, c'mon neuf, the context of Psalm 69:23 is about people not understanding Jesus because He's been 'hidden' from their view. It's not a physical eyesight thingy.

Yeah, I'm not buying it either. Certainly there are references in the bible to blindness that could plausibly describe cataracts, such as in Genesis, where Isaac is described as having "dim" vision with his advanced age.

The most interesting example, though, is found in the Book of Tobit, where the onset of his (Tobit's) blindness seems reasonably explained by cataracts, and his cure is reasonably explained by couching.

[Beyond]

Aw, c'mon neuf, the context of Psalm 69:23 is about people not understanding Jesus because He's been 'hidden' from their view. It's not a physical eyesight thingy.

Yeah, I'm not buying it either. Certainly there are references in the bible to blindness that could plausibly describe cataracts, such as in Genesis, where Isaac is described as having "dim" vision with his advanced age.

The most interesting example, though, is found in the Book of Tobit, where the onset of his (Tobit's) blindness seems reasonably explained by cataracts, and his cure is reasonably explained by couching.

I've never read Tobit. But then I've never read Tobe or not Tobe either.

[neufer]

Certainly there are references in the bible to blindness that could plausibly describe cataracts, such as in Genesis, where Isaac is described as having "dim" vision with his advanced age. The most interesting example, though, is found in the Book of Tobit, where the onset of his (Tobit's) blindness seems reasonably explained by cataracts, and his cure is reasonably explained by couching.

I've never read Tobit. But then I've never read Tobe or not Tobe either.

• A FAR MORE BELIEVABLE story than that of Shaksper of Stratford:

[b][color=#0000FF][size=150]Asmodeus as depicted in[/size] Collin de Plancy's Dictionnaire Infernal.[/color][/b]

---

<<The Book of Tobit tells the story of a righteous Israelite of the Tribe of Naphtali named Tobit living in Nineveh after the deportation of the northern tribes of Israel to Assyria in 721 BC under Sargon II. He is particularly noted for his diligence in attempting to provide proper burials for fallen Israelites who have been slain by Sennacherib, for which the king seizes all his property and exiles him. After Sennacherib's death, he is allowed to return to Nineveh, but buries a man who had been murdered on the street. That night, he sleeps in the open and is blinded by bird droppings that fall in his eyes. This puts a strain on his marriage, and he prays for death.

Meanwhile, in faraway Media, a young woman named Sarah prays for death in despair. She has lost seven husbands to the demon of lust, Asmodeus, who abducts and kills every man she marries on their wedding night before the marriage can be consummated. God sends the archangel Raphael, disguised as a human, to heal Tobit and to free Sarah from the demon.

The main narrative is dedicated to Tobit's son, Tobias, who is sent by his father to collect a sum of money that the latter had deposited some time previously in the far off land of Media. Under the guidance of Raphael, Tobias makes the journey to Media, accompanied by his dog. Along the way, he is attacked by a giant (or little) fish, whose heart, liver and gall bladder are removed to make medicines.

Upon arriving in Media, Raphael tells Tobias of the beautiful Sarah, whom Tobias has the right to marry, because he is her cousin and closest relative. He instructs the young man to burn the fish's liver and heart to drive away the demon when he attacks on the wedding night. The two are married, and the fumes of the burning organs drive the demon away to Upper Egypt, while Raphael follows him and binds him. Tobias and Sarah return to Nineveh. There, Raphael tells the youth to use the fish's gall to cure his father's blindness.>>

[orin stepanek]

I've never read Tobit. But then I've never read Tobe or not Tobe either.

I haven't either but here it is! http://en.wikipedia.org/wiki/Book_of_Tobit