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Old 2nd January 2019, 01:01 PM   #201
theprestige
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Originally Posted by Norman Alexander View Post
Also, all US military ships and boats operate on Zulu time. So could it be whichever state has the main navy headquarters?
The US Navy is headquartered at the Pentagon, in Arlington, VA.
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Old 2nd January 2019, 01:11 PM   #202
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Originally Posted by 3point14 View Post
India is moving northwards at about the same speed your fingernails grow.
As a result the nation of Nepal gets a measurable bit narrower (measured on a North/South axis) each year. Not sure of the actual number though, somewhere around a few centimeters or so.
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Old 2nd January 2019, 01:24 PM   #203
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Originally Posted by Cheetah View Post
You have been alive for more than 4.5 billion years, sort of.

Literally every living cell in your body has been functioning continuously for all that time.
And when a cell in your body dies (which happens about 300 million times per minute) it ends a previously unbroken chain of successful cellular reproduction going back all that time. ... kinda depressing.
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Old 2nd January 2019, 01:28 PM   #204
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Originally Posted by bruto View Post
It's been many years since I read that book, but I don't remember that the "aukness" of the birds is mentioned there. It reminds me, though, that it's about time to read it again. I read it first when I was about 17, and named my first car (which had no right to run at all) "St. Mael" in honor of the stone in which the missionary set forth.
Here is one of the characters in the population descended from the birds
Quote:
... a middle-class Jew called Pyrot, desirous of associating with the aristocracy and wishing to serve his country, entered the Penguin army. The Minister of War, who at the time was Greatauk, Duke of Skull, could not endure him. He blamed him for his zeal, his hooked nose, his vanity, his fondness for study, his thick lips, and his exemplary conduct.
Thus Anatole France begins his satirical chapter on the Dreyfus Affair. The capital city of Penguinia is, moreover, called Alca.
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Old 2nd January 2019, 02:30 PM   #205
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Originally Posted by Norman Alexander View Post
I suspect it is some technicality involving the dateline. Or the definitions of "most eastern" and "most western".

Also, all US military ships and boats operate on Zulu time. So could it be whichever state has the main navy headquarters?

ETA: It's the dateline thing! The Aleutians extend across the dateline into "tomorrow".

https://www.worldatlas.com/aatlas/infopage/nsewusa.htm
This was not the case while I was in the Navy. We operated on the local time zone. With reference to Zulu.
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Old 2nd January 2019, 03:23 PM   #206
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Originally Posted by Craig B View Post
Here is one of the characters in the population descended from the birds Thus Anatole France begins his satirical chapter on the Dreyfus Affair. The capital city of Penguinia is, moreover, called Alca.
Ah yes, I had forgotten Greatauk!
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Old 2nd January 2019, 03:29 PM   #207
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Having sex with hedgehogs is dangerous.
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Old 2nd January 2019, 04:24 PM   #208
Craig B
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Originally Posted by bruto View Post
Ah yes, I had forgotten Greatauk!
In the mediaeval bit of the satire we are introduced to a scholarly monk
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At that time, whilst Penguinia was still plunged in ignorance and barbarism, Giles Bird-catcher, a Franciscan monk, known by his writings under the name Aegidius Aucupis. He devoted himself with indefatigable zeal to the study of letters and the sciences.
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Old 2nd January 2019, 06:16 PM   #209
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Originally Posted by lobosrul5 View Post
Eratosthenes calculated the size of the Earth to only a very small margin of error 1600 years before Columbus tried to sail west to get to the Far East. He should have known it would've been impossible for him to reach China without running out of fresh water, even had the Americas not existed.
Alas, while possible, the claim is impossible to substantiate. The problem is that nobody knows for certain exactly how long a stadion was. See Wikipedia for a brief discussion.

Or rather, it's possible that Eratosthenes was exactly correct, but there is no firm consensus about exactly how long his units were.
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Old 2nd January 2019, 06:21 PM   #210
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A fly lands on the ceiling by doing a half-loop, rather than a half-roll.

A bumblebee can be shown to be incapable of flight. As long as you pretend it is a fixed-wing aircraft powered by piston engines and propellers.

When a boulder erupts from the earth during a winter's worth of freeze-thaw cycles, it is pulled up rather than pushed.

The reproductive channel of the human female is remarkably hostile to human sperm.

There exists a species of slime mold with 20,000 sexes.

There exists an insect which produces sperm which are longer than the producer's body.
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Old 2nd January 2019, 07:07 PM   #211
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Originally Posted by WhatRoughBeast View Post
Alas, while possible, the claim is impossible to substantiate. The problem is that nobody knows for certain exactly how long a stadion was. See Wikipedia for a brief discussion.

Or rather, it's possible that Eratosthenes was exactly correct, but there is no firm consensus about exactly how long his units were.
Seems like a worst case, note worst, that he was wrong by 10%. Seems substantiated enough to me.
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Old 2nd January 2019, 07:22 PM   #212
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Originally Posted by WhatRoughBeast View Post
Alas, while possible, the claim is impossible to substantiate. The problem is that nobody knows for certain exactly how long a stadion was. See Wikipedia for a brief discussion.

Or rather, it's possible that Eratosthenes was exactly correct, but there is no firm consensus about exactly how long his units were.
Also, Columbus would have known what the current consensus was wrt to the Earth's circumference because "the savants of Spain" had told him.


Actually, everyone he talked to told him that.

Quote:
On 1 May 1486, permission having been granted, Columbus presented his plans to Queen Isabella, who, in turn, referred it to a committee. After the passing of much time, the savants of Spain, like their counterparts in Portugal, replied that Columbus had grossly underestimated the distance to Asia. They pronounced the idea impractical and advised their Royal Highnesses to pass on the proposed venture.
https://en.wikipedia.org/wiki/Christ...t_for_a_voyage


To keep his shipmates in good spirits he also "cooked" the books on the way over.
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Old 2nd January 2019, 11:07 PM   #213
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Originally Posted by jonesdave116 View Post
Having sex with hedgehogs is dangerous.
I've heard the oft-repeated truism that hedgehogs are good at one big thing. I guess, since there are plenty of hedgehogs, that's the one.
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Old 3rd January 2019, 02:03 AM   #214
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Originally Posted by Delvo View Post
And one American state contains both the USA's easternmost points and its westernmost points.

I know you didn't start that, so no offense to you, but that is one of the dumbest (and most incorrect) pieces of "trivia" making the rounds.


If you are talking about the easternmost (or westernmost, southernmost, or northernmost) point of something you are talking about from the perspective of that something. Period. Full stop. In no logical sense would you ever be talking about its most easternmost point from the perspective of something else.


So from the perspective of the "USA", the "USA's easternmost point" would be in Maine.

It is entirely illogical to talk about it from the perspective of the Earth and its hemispheres unless you specifically said that is what you are discussing.

It would be as dumb as saying "the easternmost point in the USA changes twice a day" and leaving out "from the perspective of the sun".

Again, unless you qualify it, the perspective of the "something" can only be the "something" and nothing else.

So unless you implicitly add "from the perspective of the Earth and its hemispheres and not from the perspective of itself" that piece of trivia is hogwash.
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Old 3rd January 2019, 02:05 AM   #215
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Originally Posted by Squeegee Beckenheim View Post
God, imagine if there were "anti-periodists".


Certain branches of Mormons, as well as many fundamental branches of other religions (like the Baptist "Duggars") actually do believe that.

Or to put it more plainly: At any time that a woman is fertile, she must immediately become pregnant.
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Old 3rd January 2019, 02:09 AM   #216
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In more ways than one
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Old 3rd January 2019, 02:15 AM   #217
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Originally Posted by ahhell View Post
This was not the case while I was in the Navy. We operated on the local time zone. With reference to Zulu.
Agree.
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Old 3rd January 2019, 05:58 AM   #218
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Originally Posted by jonesdave116 View Post
Having sex with hedgehogs is dangerous.
"With a giraffe if you stand on a stool"...
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Old 3rd January 2019, 06:59 AM   #219
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Originally Posted by 3point14 View Post
"With a giraffe if you stand on a stool"...
My friend Charley referred to his mule as "stump broke"....
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Old 3rd January 2019, 07:24 AM   #220
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The "dark side of the Moon" is not the same as the "far side of the Moon". Except sometimes.
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Old 3rd January 2019, 10:26 AM   #221
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There's no blue pigment in blue jay or bluebird feathers. The blue color comes from a light scattering effect.
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Old 3rd January 2019, 10:34 AM   #222
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You can make a lead balloon that does float in air.

Mythbusters did it!
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Old 3rd January 2019, 03:23 PM   #223
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Originally Posted by attempt5001 View Post
And when a cell in your body dies (which happens about 300 million times per minute) it ends a previously unbroken chain of successful cellular reproduction going back all that time. ... kinda depressing.
Now you've gone and made me feel sad...

I tell people in my classes that the evolutionary "invention" of sexual reproduction was also the invention of death. Two of my gametes, ~half my DNA sequence, and a part of the cell guts that made up my sperm went to my sons and will continue in this billions of years saga, but all the other 10 trillion cells of which I am comprised will die.

Well, that's the way it is I guess...
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Old 3rd January 2019, 04:35 PM   #224
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Originally Posted by theprestige View Post
Not if you took out all the space between the subatomic particles of the sugar cube.

I admit to being amused by the (true) notion that most of what we think of as "solid" objects is really just interacting force fields.

My favorite scientific fact:

A pound of feathers weighs as much as a pound of lead.
I'm not sure what the meaning of pound is exactly.

If it means weight as measured with a scale then of course this is trivially true.

If instead it is a measure of mass, and we're doing the experiment in an atmoshpere, then the feathers will weigh a tiny bit less because of the different buoyancies. I'm not going to estimate by how much.

What weighs more, a ... was a common joke question around here. I saw a small treatise once that said that that smartass kid who first mentioned this was actually the first one to answer the question the proper way.
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Old 3rd January 2019, 05:44 PM   #225
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Originally Posted by alfaniner View Post
The "dark side of the Moon" is not the same as the "far side of the Moon". Except sometimes.
Specifically during full moon.

Okay, an obvious fact, but thinking about the relationship between the way things look from down here and what's actually going on up there is pretty fun, in my opinion.
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Old 3rd January 2019, 06:44 PM   #226
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A pound of gold, of course, weighs masses less than a pound of lead!
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Old 3rd January 2019, 08:26 PM   #227
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Originally Posted by Giordano View Post
Now you've gone and made me feel sad...

I tell people in my classes that the evolutionary "invention" of sexual reproduction was also the invention of death. Two of my gametes, ~half my DNA sequence, and a part of the cell guts that made up my sperm went to my sons and will continue in this billions of years saga, but all the other 10 trillion cells of which I am comprised will die.

Well, that's the way it is I guess...
Indeed. An amazing and slightly sobering perspective. Cheers!
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Old 3rd January 2019, 10:11 PM   #228
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Originally Posted by jonesdave116 View Post
Having sex with hedgehogs is dangerous.
Certainly is for the hedgehog
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Old 4th January 2019, 12:34 AM   #229
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The inventor of the cat flap was Isaac Newton

Jupiter was originally the nearest planet to the Sun

Tardigrades can survive temperatures one degree above absolute zero

Men have nipples because during pregnancy the uterus is flooded with oestrogen
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Old 4th January 2019, 03:30 AM   #230
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The units of the Hubble Constant are an inverse time, whose value is approximately equal to one over the age of the universe.
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Old 4th January 2019, 06:07 AM   #231
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Originally Posted by surreptitious57 View Post
Men have nipples because during pregnancy the uterus is flooded with oestrogen

I thought we all have nipples because we share the same DNA.
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Old 4th January 2019, 08:30 AM   #232
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Originally Posted by Myriad View Post
There's no blue pigment in blue jay or bluebird feathers. The blue color comes from a light scattering effect.
It's called "Irridescense". Easiest to see on pigeon necks. It's also related to "metallic" paints, which are actually small mica flakes in the paint. Mica flakes will also suspend in many liquids, like those shimmery shampoos. That effect is used in movie special effects, like "Worm Holes" and Star Gates. You can buy the powder on eBay as "mica powder dry lube". But it's cheapest at a pottery clay supplier. It's cheap enough to use it as a filler in plastics, like my wiper blade parts on my pick up truck. I guess the plastic has weathered away, now they are glittery.

And I saw a rainbow inside my new shotgun choke tube yesterday. I guess it was a combination of the conical taper and the texture of the ground surface. It made me think of a kaleidoscope. I suspect it will go away when the carbon of the first shot fills the surface texture.
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Old 4th January 2019, 08:32 AM   #233
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Originally Posted by Cheetah View Post
I thought we all have nipples because we share the same DNA.
Yeah dat. But the prolactin in the mother can make the baby's nipples give milk. It's called Witches Milk.
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Old 4th January 2019, 08:45 AM   #234
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Originally Posted by TheGnome View Post
I'm not sure what the meaning of pound is exactly.

If it means weight as measured with a scale then of course this is trivially true.

If instead it is a measure of mass, and we're doing the experiment in an atmoshpere, then the feathers will weigh a tiny bit less because of the different buoyancies. I'm not going to estimate by how much.

...
You would want to use the density of the collagen that the feathers are made form. I don't think it would be any where near as big as the feathers.

But hmmm, feathers being hollow tubes, I wonder if birds can be filling the tubes with hydrogen?* That would make a big difference between weigh and mass, since the hydrogen would subtract from the weight but add to the mass.

* If not, I wonder if we can GMO some kind of enzyme that separates the hydrogen from water? Make birds into blimps? No, I think they would be dirigibles. oooh, I just got rich- limitless free hydrogen without the electricity costs of electrolysis! Enzymes would be a really cheap catalyst.
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Old 4th January 2019, 08:46 AM   #235
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Originally Posted by Myriad View Post
There's no blue pigment in blue jay or bluebird feathers. The blue color comes from a light scattering effect.
I'm reminded of this:

https://xkcd.com/1818/

Yes, I know it's not entirely the same.
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Old 4th January 2019, 08:46 AM   #236
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Originally Posted by casebro View Post
It's called "Irridescense". Easiest to see on pigeon necks. It's also related to "metallic" paints, which are actually small mica flakes in the paint. Mica flakes will also suspend in many liquids, like those shimmery shampoos. That effect is used in movie special effects, like "Worm Holes" and Star Gates. You can buy the powder on eBay as "mica powder dry lube". But it's cheapest at a pottery clay supplier. It's cheap enough to use it as a filler in plastics, like my wiper blade parts on my pick up truck. I guess the plastic has weathered away, now they are glittery.

And I saw a rainbow inside my new shotgun choke tube yesterday. I guess it was a combination of the conical taper and the texture of the ground surface. It made me think of a kaleidoscope. I suspect it will go away when the carbon of the first shot fills the surface texture.

Not all blue feathers are iridescent. Some are (and some feathers of other colors are as well), such as those of grackles, hummingbirds, birds of paradise, and peacocks. But bluebird and blue jay feathers appear as a plain matte blue. In those cases it's internal scattering between the fibers, not surface iridescence.
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Old 4th January 2019, 08:55 AM   #237
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Originally Posted by 3point14 View Post
I'm reminded of this:

https://xkcd.com/1818/

Yes, I know it's not entirely the same.

It does make a good point though. It's why I phrased it as "...don't have blue pigment," rather than going overboard and claiming e.g. "bluebirds (or bluebird feathers) aren't really blue" as some gee-whiz popular science writers sometimes do. Which is silly, of course they're blue; they preferentially reflect blue light. It's just that the reason they do so is different from what we might expect. If you were looking for natural dyes and tried to develop a blue dye by mashing up a bunch of blue jay feathers, you'd be disappointed in the results.
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Old 4th January 2019, 09:19 AM   #238
Dave Rogers
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If all the hydrogen in my body were replaced by deuterium, I'd be about 20 pounds heavier.

Dave
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Old 4th January 2019, 09:31 AM   #239
Ziggurat
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Originally Posted by Dave Rogers View Post
If all the hydrogen in my body were replaced by deuterium, I'd be about 20 pounds heavier.

Dave
You would also die.

Deuterium can form all the same chemicals as hydrogen, but it's not chemically identical. In particular, chemical reactions happen a bit slower with deuterium than with hydrogen, and since complex organisms are very sensitive to reaction rates, the difference is enough to kill you. You can tolerate some fraction of H to D substitution, but not 100%.
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Old 4th January 2019, 09:41 AM   #240
Dave Rogers
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Originally Posted by Ziggurat View Post
You would also die.
Yes, but I'd die heavier!

Dave
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Me: So what you're saying is that, if the load carrying ability of the lower structure is reduced to the point where it can no longer support the load above it, it will collapse without a jolt, right?

Tony Szamboti: That is right
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