Today I Learned

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Today I learned that cleaning a white hat can be done with bleach cleaner, but it’s important to rinse it before wearing it again. I also discovered that "oyster veneering," a woodworking technique from the late 1600s, is experiencing a minor revival despite its labor-intensive nature. Additionally, I learned that the factorial of 23 (23!) equals 25,852,016,738,884,976,640,000, which interestingly has 23 digits, a unique coincidence among factorials. I found out that medical specialists often spend less than 10 minutes with patients, and that watching TV can contribute to weight gain. Other insights included the fact that a kiss can transfer around 80 million microbes, and that bureaucracy can sometimes hinder employment opportunities. The discussion also touched on various trivia, such as the emotional sensitivity of barn owls and the complexities of gravitational lensing around black holes.
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  • #6,152
This year I learned you can create fusion in a plasma stream through the "Z-Pinch" Lorentz force created as ions move through their own magnetic field. Reportedly they have hit 800,000 amps in their plasma stream and hope to hit 1 megaamp soon.
https://www.zapenergy.com//

Generally
https://pubs.aip.org/aip/jap/article/127/20/200901/157297

Also, Theta pinch
https://www.helionenergy.com/
https://www.osti.gov/biblio/6559608

In the case of Z pinch, this has been around since the 1950s but they could never control the pinch (as I understand it). But with modern controls and modeling, it may be possible to control this now.
 
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  • #6,154
TIL a 2021 University of New Hampshire survey found that 83% of Americans believe the earth revolves around the sun. 19% flat earth, 25% the earth is not billions of years old, 28% microchip implant vaccinations, and 29% no NASA moon landing. But it's not all discouraging. 94% are able to find the USA on a map of the world.
 
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  • #6,155
Hornbein said:
TIL a 2021 University of New Hampshire survey found that 83% of Americans believe the earth revolves around the sun. 19% flat earth, 25% the earth is not billions of years old, 28% microchip implant vaccinations, and 29% no NASA moon landing. But it's not all discouraging. 94% are able to find the USA on a map of the world.
I just saw that some well-known flat earther went to Antarctica to prove the earth was flat. He argued a 24-hour sun was impossible on a flat earth and disproved his own claim. He thought the claims of a 24-hour sun were fake too! LOL! But I give him credit for being honest. He did actually present his results to his followers!

So you can all relax now. The earth really is spherical. Some influencer says so!

On a related note, the human race is doomed.
 
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  • #6,156
Why Antarctica? That sounds a bit inconvenient when you could just go to northern Canada, Alaska, Greenland, or northern Scandinavia …
 
  • #6,157
Orodruin said:
Why Antarctica? That sounds a bit inconvenient when you could just go to northern Canada, Alaska, Greenland, or northern Scandinavia …
I wasn't going to try to understand his "reasoning".
 
  • #6,158
Orodruin said:
Why Antarctica? That sounds a bit inconvenient when you could just go to northern Canada, Alaska, Greenland, or northern Scandinavia …
Because his assumptions are back to front. He was expecting to go somewhere and film the Sun being below the horizon and ask hard questions of all the paid actors who live locally and lie to the world about it. If he wasn't as near to the pole as he could get, those lying liars who claim to have seen 24 hour sunlight could all claim he hadn't gone far enough south or gone at the wrong time of year or something. Also, most flat-Earthers seem to believe the Arctic is the center of the disc and the Antarctic is the rim, so he'd expect the largest deviation from spherical behaviour there.

It's not a totally stupid experimental design given his idiotic initial beliefs and the challenges he expected to the results he expected.

I've occasionally thought it would be an interesting school project to demonstrate that the world is a sphere. You need cooperation between schools as far apart as possible and phones, and with that the actual measurements are fairly trivial - altitude of the Pole Star and altitudes and compass bearings to a couple of pre-agreed others at a pre-agreed time should be enough to establish your latitude and your longitude difference.
 
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  • #6,159
Orodruin said:
Why Antarctica? That sounds a bit inconvenient when you could just go to northern Canada, Alaska, Greenland, or northern Scandinavia …
The Flat-Earth model he accepted allows for a 24 hr sun in the Arctic, but not one in Antarctica. It was based on the Gleason map projection with the North pole at the center of the disk, and Antarctica a ring forming the outer edge. The Sun in this model circled above the disk between the Tropics of Cancer and Capricorn.
 
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  • #6,160
Ivan Seeking said:
I just saw that some well-known flat earther went to Antarctica to prove the earth was flat. He argued a 24-hour sun was impossible on a flat earth and disproved his own claim. He thought the claims of a 24-hour sun were fake too! LOL! But I give him credit for being honest. He did actually present his results to his followers!

So you can all relax now. The earth really is spherical. Some influencer says so!

On a related note, the human race is doomed.
Of course, a lot of the Flat-Earth community are now claiming that he is a paid shill. Whether he always was as part of a long con, or just recently bought off is unclear.

This whole thing was an exercise of "The enemy of my enemy is my friend" The person who proposed and funded this trip is a pastor who is a young Earth creationist. He paid for 2 flat Earth proponents and 2 globe proponents to make the trip (others went too, but had to pay their own way). His motive was to separate FE from YEC, as many FEs are also YECs, and he felt that FE made YEC look bad. To my knowledge, none of the globe proponents were YECs, but were willing to take his offer in order to provide further evidence against the flat Earth.
 
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  • #6,161
This year I learned about Suction Specific Speed - a dimensionless number that provides a key bit of information about centrifugal pumps that you cannot derive from the pump curve (at least not in any obvious way).

1735410628510.png


Industry experience has shown that when the Net Suction Specific Speed has a value less than 6000 ( in US units), the pump is in danger of recirculation or cavitation, and loss of flow. This does require the pump curve is adjusted for viscosity.
https://www.michael-smith-engineers.co.uk/resources/useful-info/specific-speed#:~:text=Industry experience has shown that,in pump wear and maintenance
A closely related equation, the Specific Speed determines the most efficient type of impeller and is based on the net Head at the Best Efficiency Point rather than the Net Positive Suction Head. {NPSH]
 
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  • #6,162
Ivan Seeking said:
This year I learned about Suction Specific Speed ...
colbert bus.gif

I forgot the thread title, and thought we awere still talking about Flat Earth, and assumed Suction Specific Speed was going to be the Flerfers' latest rationalization about the Sun's movements.
 
  • #6,163
This year Last year I learned about salt-cooled fission reactors and other things :wink:.
https://www.terrapower.com/
(a Bill Gates company)

On Netflix
1735789567227.png
 
  • #6,164
TIL about windcatchers.
Neglected by modern architects in the latter half of the 20th century, the early 21st century saw them used again to increase ventilation and cut power demand for air-conditioning. Generally, the cost of construction for a windcatcher-ventilated building is less than that of a similar building with conventional heating, ventilation, and air conditioning (HVAC) systems. The maintenance costs are also lower. Unlike powered air-conditioning and fans, windcatchers are silent and continue to function when the electrical grid power fails (a particular concern in places where grid power is unreliable or expensive).
 
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  • #6,165
TIL
https://en.wikipedia.org/wiki/Interesting_number_paradox said:
The interesting number paradox is a humorous paradox which arises from the attempt to classify every natural number as either "interesting" or "uninteresting". The paradox states that every natural number is interesting. The "proof" is by contradiction: if there exists a non-empty set of uninteresting natural numbers, there would be a smallest uninteresting number – but the smallest uninteresting number is itself interesting because it is the smallest uninteresting number, thus producing a contradiction.

Furthermore, I also learned that it could be applied to people, thus every person is interesting because the most uninteresting person will always be interesting.
 
  • #6,166
jack action said:
TIL


Furthermore, I also learned that it could be applied to people, thus every person is interesting because the most uninteresting person will always be interesting.
I rode a train from Turpan to Kashgar. The topography was exactly the same for hundreds of miles. I found this fascinating.

Flying back on the airplane I could see that we had ridden alongside a mountain range that was completely straight and the same height the whole way.
 
  • #6,167
Hornbein said:
I rode a train from Turpan to Kashgar. The topography was exactly the same for hundreds of miles. I found this fascinating.

Flying back on the airplane I could see that we had ridden alongside a mountain range that was completely straight and the same height the whole way.
From the North end of Los Angeles to the South end of Orange County, you can drive in solid city for over 100 miles.
 
  • #6,168
Last year I learned how to make a valve for liquid salt running at over 800 C
 
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  • #6,169
Ivan Seeking said:
From the North end of Los Angeles to the South end of Orange County, you can drive in solid city for over 100 miles.
More so on the east coast.
 
  • #6,170
BillTre said:
More so on the east coast.
Really? I did not know that! In S California it would be solid city from LA to San Diego, but the San Onofre nuclear power plant required a large unpopulated radius. That is shut down now but I haven't been down there for a long time. I don't know if that area is filling in yet or not. They still have 3.5 million pounds of nuclear waste.
 
  • #6,171
Northern VA to Massachusetts at east.
They have a railroad too.
 
  • #6,172
What do we define as solid city? Pretty sure I could drive from one end of the Golden Horseshoe (Greater Toronto and burbs) to the other and it would be city the whole way. That's 100 miles.
 
  • #6,173
DaveC426913 said:
What do we define as solid city? Pretty sure I could drive from one end of the Golden Horseshoe (Greater Toronto and burbs) to the other and it would be city the whole way. That's 100 miles.
I meant non-stop buildings, asphalt, and concrete.
 
  • #6,174
Today I learned that Mormon founder Joseph Smith ran for President in 1844. During that time he was mayor of Navoo, Illinois. Navoo attempted to secede from the Union. It also had an army of 2500 men, one third the size of the US army. This Mormon army destroyed the printing press of some anti-Smithites. This inspired such outrage that Smith invoked martial law in Navoo. Illinois charged him with treason. Smith fled the state but returned when the governor guaranteed his safety. A big mob stormed the jail and killed Smith. He is said to have been the first presidential candidate assassinated.
 
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  • #6,175
jedishrfu : Today I learned that Lagrange was Italian and that he lamented the execution of Lavoisier in France during the French Revolution with the quote:

"It took them only an instant to cut off this head and a hundred years might not suffice to reproduce it's like."

Lavoisier was also the head tax collector of Paris, a very lucrative post. To facilitate the collection of duties on the import and export of goods he had all of Paris surrounded by a wall with customs inspectors at the gates. In my opinion hatred of this was a major cause of the revolution.

In those days it was not unusual for very rich people to become scientists in order to avoid gambling addictions, alcoholism, syphilis, and other common vices of idle hands. Henry Cavendish was perhaps the richest man in England.
 
  • #6,176
Hornbein said:
head tax collector
… he certainly had his head collected … 🥲
 
  • #6,177
TIL Spain needs a new flag guy

 
  • #6,178
Ivan Seeking said:
I meant non-stop buildings, asphalt, and concrete.
OK, yes. That describes the Golden Horseshoe.

I think Canada is laid out a bit differently than America. We bunch all our urban areas together.
1736125873880.png


And most of us huddle as close as humanly possible to the border where there's warmth.

1/4 of all Canadians (40m) live in the Golden Horseshoe (9.7m).
1736126165995.png
 
  • #6,179
Hornbein said:
During that time he was mayor of Navoo, Illinois.
Nauvoo
 
  • #6,180
DaveC426913 said:
OK, yes. That describes the Golden Horseshoe.

I think Canada is laid out a bit differently than America. We bunch all our urban areas together.
View attachment 355389

And most of us huddle as close as humanly possible to the border where there's warmth.

1/4 of all Canadians (40m) live in the Golden Horseshoe (9.7m).
View attachment 355390
To really leave an impression, this map does the trick:

sjbijiqb0u211.png
 
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  • #6,181


Gives new meaning to the name pufferfish
 
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  • #6,182
Tanigawa-dake is sometimes called "mountain of death". As of December 2014, since its initial exploration and route-finding in the early 1930s, a total of 805 people have died on Tanigawa-dake.[1][2][3] (Compare with the approximately 200 people who have died on Mt. Everest over a comparable period.) In 1943, a climbing party disappeared on the mountain. They were not found until another climbing party stumbled upon their remains in 1973. In the 1960s, there was a famous rescue attempt of Japanese climbers on the main face who had died of exposure. Their bodies were eventually brought down when the Japanese Self-Defense Forces cut the rope with gunfire in order to retrieve the bodies.[4]
 
  • #6,183
Learned about this alleged airburst that destroyed an ancient Mesopotamian city in the otherwise good The Earth Transformed by Frank Pankopan. The story came out in Nature and the Smithsonian Article referenced below, the wiki article indicates considerable skepticism has arisen over the last few years though



The destruction of Tall el-Hammam, a Bronze Age city in the Jordan Valley, by an exploding comet or meteor may have inspired the biblical story of Sodom and Gomorrah, a new study suggests. (“[N]otoriously sinful cities,” Sodom and Gomorrah’s devastation by sulfur and fire is recorded in the Book of Genesis, according to Encyclopedia Britannica.)

https://www.smithsonianmag.com/smar...e-inspired-biblical-story-of-sodom-180978734/
 
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  • #6,184
TIL that Florida's state bird is not the flamingo. It’s the mockingbird. This year will see the eighth attempt to fix that, in the state legislature.

 
  • #6,185
jtbell said:
TIL that Florida's state bird is not the flamingo. It’s the mockingbird. This year will see the eighth attempt to fix that, in the state legislature.


I assume all "Bill to kill the Mockingbird" jokes have already been done?
 
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  • #6,186
Maybe they should make a movie about it.

KillBill3.jpg
 
  • #6,187
Last year I learned how handy an Observium unit can be for network diagnostics.
 
  • #6,188
For almost 29 years after the end of World War Two, Hiroo Onoda carried out guerrilla warfare on Lubang Island in the Philippines, on several occasions engaging in shootouts with locals and the police. Onoda initially held out with three other soldiers: one surrendered in 1950, and two who were killed, one in 1954 and one in 1972. They did not believe flyers saying that the war was over. Onoda was contacted in 1974 by a Japanese explorer, but still refused to surrender until he was relieved of duty by his former commanding officer, Major Yoshimi Taniguchi, who flew from Japan to Lubang to issue the order.

Onoda surrendered on 10 March 1974 and received a hero's welcome when he returned to Japan. That year he wrote and published his autobiography. He later followed his brother to Brazil, where he joined an established Japanese immigrant community in Mato Grosso do Sul. He set up a cattle ranch. After 1984, he spent three months of the year in Brazil and the rest of his time in Japan
 
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  • #6,189
The best speech to promote A4 (at least, to nerds with OCD):

 
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  • #6,190
TIL Darwin's grave vandalised by just stop oil.
 
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  • #6,191
jack action said:
To really leave an impression, this map does the trick:

Related: 70% of Canadians live south of the main readily identifiable border with the US (the 49th parallel).
 
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  • #6,192
Pacific bluefin tuna are large, migratory fish found throughout the biggest ocean on Earth. A typical Pacific bluefin weighs about 130 pounds, but occasionally, these iridescent swimmers can balloon in size, topping the scales at nearly 1,000 pounds. They feast on squid and various types of fish, including herring, anchovies, saury, sardines and mackerel.

Unlike most other fish, bluefin tuna are warm-blooded. They have a unique blood vessel structure, known as a countercurrent exchanger, that allows them to retain body heat, even when they’re submerged in frigid waters. This adaptation allows them to inhabit cold areas and dive up to 1,800 feet deep. It also makes them fast and powerful swimmers: The fish are known to cross the Pacific Ocean in just 55 days.
https://www.smithsonianmag.com/smar...-million-at-a-japanese-fish-market-180985799/
 
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  • #6,193
TIL that a whetstone is used while wet.
 
  • #6,194
TIL that the "finger gun" gesture is now verboten in schools.
1736952713607.png

I was informed - and chastised - by my 5yo gd.
 
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  • #6,195
DaveC426913 said:
TIL that the "finger gun" gesture is now verboten in schools.
View attachment 355892
I was informed - and chastised - by my 5yo gd.
Are you some kind of terrorist? Jeez!

Actually, it is a gesture that can mean, I'm going to kill you. So it is understandable.
 
  • #6,196
TIL not to do this

 
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  • #6,197
DaveC426913 said:
TIL that the "finger gun" gesture is now verboten in schools.
View attachment 355892
I was informed - and chastised - by my 5yo gd.
In some areas of Japan the finger gun is such a tradition that victims will pretend to have been hit. Even strangers will do this.
 
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  • #6,198
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  • #6,199
TIL that
Jayden Daniel's fourth down conversion rate is better than
Michael Jordan's free throw percentage.
 
  • #6,200
BillTre said:
TIL that
Jayden Daniel's fourth down conversion rate is better than
Michael Jordan's free throw percentage.
He's still going to lose against the Lions on Saturday. :oldwink:
 

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