Post #173,907
9/13/04 11:03:43 AM
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APOD asks "What caused this ring of colors?"
[link|http://antwrp.gsfc.nasa.gov/apod/astropix.html|link]
The picture seems to be of the photographers shadow with the sun directly behind his head showing a circular rainbow with the focus on a construction site floor of concrete(?) with dirt/oil/floor cleaner(?) all over it. Perhaps a dust haze in air.
My guess is that it was caused by the steel-toed boot fairies of circular rainbows.
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It is much harder to be a liberal than a conservative. Why?
Because it is easier to give someone the finger than it is to give them a helping hand.
Mike Royko
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Post #173,918
9/13/04 11:30:12 AM
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Photoshop.
;-j
He doesn't say whether it's real or something seen in the photograph. I assume it's real.
Rainbows like that are usually caused by light refracting through droplets of water or ice crystals. Hints can probably be found by looking at earlier [link|http://antwrp.gsfc.nasa.gov/apod/|APODs] and [link|http://epod.usra.edu/|ESPODs]. We can say that something above him has a different refractive index than air. From the relative sizes of his shadow and the diameter of the circle, the refractive index can probably be determined.
Maybe he's got a crystal ball sitting on his head. >:-)
I'm not sure what's causing it in this case and don't have time to try to figure it out. ;-)
Cheers,
Scott.
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Post #173,985
9/13/04 4:57:13 PM
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extremely cool
-drl
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Post #174,153
9/14/04 9:37:50 AM
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Re: APOD asks "What caused this ring of colors?"
The light and source of the rainbow are obviously behind him - hence the shadow. The shadow is sharp, so I would imagine the light source is small or going through a small hole. My guess is the pinhole is causing the refraction, and of course red light being lower frequency would be bent more and be on the outer ring.
~~~)-Steven----
"I want you to remember that no bastard ever won a war by dying for his country.
He won it by making the other poor dumb bastard die for his country..."
General George S. Patton
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Post #174,159
9/14/04 10:00:12 AM
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Shadow is from the Sun
Hint: you can estimate the angular size of the ring and match it up with known atmospheric phenomena.
-drl
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Post #174,160
9/14/04 10:04:44 AM
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Re: Shadow is from the Sun
Yes, that is what I believe myself, but the shadow is too sharp for it to be from the full sun. If the sun were shining directly behind him in open air, there would be some feathering on the edge of his shadow. That's part of why I believe it's shining through a pinhole.
~~~)-Steven----
"I want you to remember that no bastard ever won a war by dying for his country.
He won it by making the other poor dumb bastard die for his country..."
General George S. Patton
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Post #174,184
9/14/04 11:36:10 AM
9/14/04 11:41:32 AM
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You should really change the link to:
[link|http://antwrp.gsfc.nasa.gov/apod/ap040913.html|Link] The fact that the shooter is in the picture is immaterial. Notice the greater intensity inside the ring as compared to outside. This mean *SOME* type of light gathering device. What kind? A Lense? Nah, to obvious, but still a refracting lense might work. A Prism? Nah. A Mirror? Maybe. A Highly polished something? Maybe. Some kind of Communications Dish? Maybe. Lead Crystal? Hmmm. That would also give that order of color at the edges. The Shadows lineup in the circle and outside the circle. Mean something like Noon or the time they are lined up. This is my guess: How about a mirror that reflects the Noon Sun through a Lead Glass Decorative Window (acting as a refracting lense of sorts), High atop a Building? -- [link|mailto:greg@gregfolkert.net|greg], [link|http://www.iwethey.org/ed_curry|REMEMBER ED CURRY!] @ iwetheyNo matter how much Microsoft supporters whine about how Linux and other operating systems have just as many bugs as their operating systems do, the bottom line is that the serious, gut-wrenching problems happen on Windows, not on Linux, not on Mac OS. -- [link|http://www.eweek.com/article2/0,1759,1622086,00.asp|source]Here is an example: [link|http://www.greymagic.com/security/advisories/gm001-ie/|Executing arbitrary commands without Active Scripting or ActiveX when using Windows]
Edited by folkert
Sept. 14, 2004, 11:41:32 AM EDT
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Post #174,193
9/14/04 11:58:29 AM
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It's "of the Day". You snooze, you lose.
-----------------------------------------
It is much harder to be a liberal than a conservative. Why?
Because it is easier to give someone the finger than it is to give them a helping hand.
Mike Royko
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Post #187,120
12/15/04 3:05:32 PM
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If anyone was interested in the explanation
it's [link|http://space.mit.edu/~lewin/apod/|here]
~~~)-Steven----
"I want you to remember that no bastard ever won a war by dying for his country.
He won it by making the other poor dumb bastard die for his country..."
General George S. Patton
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Post #187,121
12/15/04 3:06:09 PM
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Thanks!
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Post #187,125
12/15/04 3:32:15 PM
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Neat!
Imric's Tips for Living
- Paranoia Is a Survival Trait
- Pessimists are never disappointed - but sometimes, if they are very lucky, they can be pleasantly surprised...
- Even though everyone is out to get you, it doesn't matter unless you let them win.
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Nothing is as simple as it seems in the beginning,
As hopeless as it seems in the middle,
Or as finished as it seems in the end.
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Post #187,152
12/15/04 9:43:49 PM
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Fascinating --
And he answered 3K e-mails! Punctiliously driven or just a Gentleman!?
What are the odds of someone spilling a bunch of \ufffdmm glass beads in a propitious spot + a guy with a polarizer in his pocket! Love. It.
(Alas, my then sole Geiger wasn't calculator-sized, during days after Chernobyl -- or I'd have carried it about, too. Different strokes.)
Sounds like a no-nonsense ..but Fun lecturer; maybe there will be pics of his indoor demo.
Ah... the sheer Terror of learning a whole lot of stuff at breakneck speed Or Else... No room for BS on That test.
{sniff}
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Post #187,205
12/16/04 3:10:14 PM
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Dam.
I should e-mailed him... I was closer than the LOT of you... :-P
-- [link|mailto:greg@gregfolkert.net|greg], [link|http://www.iwethey.org/ed_curry|REMEMBER ED CURRY!] @ iwetheyNo matter how much Microsoft supporters whine about how Linux and other operating systems have just as many bugs as their operating systems do, the bottom line is that the serious, gut-wrenching problems happen on Windows, not on Linux, not on Mac OS. -- [link|http://www.eweek.com/article2/0,1759,1622086,00.asp|source]Here is an example: [link|http://www.greymagic.com/security/advisories/gm001-ie/|Executing arbitrary commands without Active Scripting or ActiveX when using Windows]
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Post #188,519
12/29/04 6:57:54 PM
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Double rainbow!____ici!!
Deluge all around except.. a shaft of light and complete clearing, just over ma maison et tout pr\ufffds - (I think I saw a fleeting LRPD streak across the sky; but as it was sl. magenta-shifted; approaching? - I ducked)
Reversed color/freq. sequence of the two, as prescribed.. the large outer arc did not persist beyond ~ 90\ufffd, but the inner displayed about the most saturated hues I've seen, across a full diameter.. ends/pot-o-gold not quite visible from my vantage. Many minutes; pity no 10 MB digicam - shoulda hauled out the Canon AL-1
Once again, Alchemy transcends the banal homo-caused deep-shit..
Thanks! GRR et Alia
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