Today I Learned

  • Thread starter Greg Bernhardt
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In summary: 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...brains."
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Today I learned that the JunoCam, the camera aboard the Juno spacecraft orbiting Jupiter, uses the exact same camera sensor that my own astrophotography camera uses: the Kodak KAI-2020 sensor.
 
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  • #3,327
Today I learned that no one knows if ##\pi + e ## is rational or irrational.

youtu.be/1LoSV1sjZFI?t=364
 
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  • #3,328
Drakkith said:
what it's like to have a tooth fall apart in your mouth
The first time that happens is most upsetting. After a few you get used to it.
 
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  • #3,329
Today I learned that an exonym is a word applied to a "a geographical place, group of people, individual person, or a language/dialect" by an outsider.

I also learned that "calque" (a great Scrabble word) is a word or phrase that is taken as a literal translation from another language. Wikipedia gives a list. (It is not always clear to me, though, why some of those examples are "borrowed" and not simple translations.
 
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  • #3,330
Fewmet said:
(It is not always clear to me, though, why some of those examples are "borrowed" and not simple translations.
These lists tend to grow by everyone adding their favorite words, fitting or not. Obvious nonsense is filtered out by Wikipedia's control mechanisms, but "it's not clear how fitting this is" has a good chance to stay in the article.
 
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TIL that a cross between a sturgeon and paddlefish was inadvertently created by scientists in a lab.

Hybrid:
Screen Shot 2020-07-20 at 11.39.47 AM.png


Sturgeon:
Screen Shot 2020-07-20 at 11.47.33 AM.png


Paddlefish:
Screen Shot 2020-07-20 at 11.45.40 AM.png


These fish (sturgeon and paddlefish) are both part of ancient evolutionary lineage that diverged more maybe 140 MYA.
They both have lots of chromosomes (from previous rounds of genome doubling) which may make them more amenable to having a hybrid function genome.
 
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  • #3,332
BillTre said:
inadvertently created by scientists in a lab
Inadvertently? Did they just leave a gentleman sturgeon and a lady paddlefish in a tank and discover they could breed when they were woken by the patter of tiny fins?
 
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  • #3,333
No they were doing in vitro fertilizations (combine sperm and unfertilized eggs in a dish, this is done a lot on some fish farms and in zebrafish labs), but mixed up the species.
 
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  • #3,334
BillTre said:
No they were doing in vitro fertilizations (combine sperm and unfertilized eggs in a dish, this is done a lot on some fish farms and in zebrafish labs), but mixed up the species.
Sounds a lot like unsafe sex to me!
 
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  • #3,335
You can get tapeworm ( Taenia saginata ) from eating beef that isn't well done. They can live in your intestines for many years without symptoms.
 
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TIL that there is such a thing like a sunflower set.
 
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Took a minute to filter out all the plant hits: https://www.math.ias.edu/csdm/files/Archives/11-12/nalon_on_sunflowers_and_matrix_multiplication.pdf (PDF)
 
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Terry Tao just blogged about sunflowers.
 
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  • #3,339
Keith_McClary said:
Terry Tao just blogged about sunflowers.
That's where I read it.
 
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  • #3,340
If a launch takes place just before sunset or just after sunrise, you might see the 'Twilight Phenomenon' which occurs when the exhaust of a rocket, which condenses and expands in the upper atmosphere, is illuminated by high altitude sunlight.

The SpaceX Falcon 9 launch back in 2018:
 
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  • #3,341
SAOCOM 1A from the west coast.
Note the first stage which separates and then flies back to land. It was the second flight (out of 5) for this booster.
 
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TIL:

()() is not a palindrome, but )(() is.
 
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  • #3,343
TIL that in Japan, you give gifts with both hands and you receive gifts with both hands
 
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  • #3,344
TIL about Benford's Law. My wife was listening to Connected on Netflix with host Latif Nasser of WNYC RadioLab. One has to subscribe to Netflix. https://www.netflix.com/title/81031737 See the trailer for Season 1.

Nasser interviews scientists and technologists about topics in science and technology.
https://www.wnyc.org/people/latif-nasser/

One program was on Benford's law and how it is manifest in many different areas.
RadioLab (Jad Abumrad and Robert Krulwich) did a program on Benford's Law in November 2009.
https://www.wnycstudios.org/podcasts/radiolab/segments/91699-from-benford-to-erdos

Others have studied, or reported on, Benford's Law
https://granitegeek.concordmonitor....id-data-with-a-weird-frequency-of-digits-law/
https://www.isaca.org/resources/isa...eets-and-benfords-law-to-test-accounting-data

Anyway, back to Connected on Netflix.
One program discussed dust from the Sahara Desert that flows across the Atlantic Ocean to the Amazon in Brazil. Turns out, the Amazon gets a lot of phosphate from the Sahara, almost as much as gets washed away by the rain and rivers.

Another story was on Robert Fitzroy and weather prediction
https://en.wikipedia.org/wiki/Robert_FitzRoy

Yet another story is about correlating separate events, e.g., rainfall in Africa with outbreaks of mosquito-borne diseases.
 
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TIL a bald eagle took down a government drone over Lake Michigan.
NY Times article.
Hunter King, a drone pilot at the Michigan Department of Environment, Great Lakes, and Energy, was surveying an area of the lake near the state’s Upper Peninsula last month when the drone started “twirling furiously” after it indicated that a propeller had been torn off.
“When he looked up, the drone was gone, and an eagle was flying away,” said the department, whose name is abbreviated E.G.L.E.
A couple who regularly spends time watching eagles go after sea gulls in the area witnessed the battle but were surprised when they learned that it was a drone that had been downed in the fight, the department said.

Why the attack?
The department speculated that the eagle could have attacked because of a territorial dispute, because it was hungry “or maybe it did not like its name being misspelled.”
Julia Ponder, executive director of the Raptor Center at the University of Minnesota, said on Saturday that it was likely because the drone had encroached on the eagle’s territory.
 
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  • #3,346
TIL: The border between Austria and Italy changes over time. It depends on how much ice some glaciers have. In many places it's defined as the watershed, and after some discussion they agreed to consider glaciers as "ground", so now it's the watershed on top of the glacier - but glaciers change. Short-term changes are not automatically changing the border but they lead to people re-evaluating the precise place.

German source (PDF), article 3

I found this looking up stuff about Ötzi, who was found near the watershed - and might have contributed to the re-definition of the border.
 
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  • #3,347
Today I learned that Jennifer Aniston has the birthday the same day as I do. :oldbiggrin:
 
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  • #3,348
The Samsung Galaxy A20 compass application shows a clearly higher magnetic field in teslas when a refrigerator magnet is taken near it, but it doesn't return to the correct value of about 50 ##\mu##T before the phone is shaked a bit. For some reason, having the magnet nearby didn't mess up the direction the compass pointed at, it only affected the field strength measurement.
 
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TIL learned that there are several ongoing efforts to shame the Astros (baseball team) for their cheating, even during the pandemic when they can't boo them in stadiums (NY Times article here):
Wilson took action. He hired a plane to fly above Oakland Coliseum during batting practice before an Athletics-Astros game, towing a sign that read, “Houston Asterisks.”
Wilson and others are carrying out an ongoing, underground opposition campaign against the Astros. With an assist from a widely followed Twitter account called 2020 Astros Shame Tour, Wilson raised the $1,200 for the flight in less than 24 hours. So
The anti-Astros movement has adopted a few heroes along the way. Among them is Trevor Bauer, the outspoken Cincinnati Reds pitcher who has written about the “bad blood” many M.L.B. players still have for the Astros.
Another is Ramon Laureano, the Athletics outfielder who was hit by an Astros pitch on Aug. 8, then engaged in a shouting match with Alex Cintron, Houston’s hitting coach, charged the Astros dugout and incited a bench-clearing fracas that flouted any sense of physical distancing.
Kelly, a Dodgers reliever, earned his special status on July 28 — not so much for throwing a fastball behind Bregman’s head during a game in Houston but because he later taunted Correa with a pouty-face expression that incited another benches-clearing encounter and has since been canonized on social media and emblazoned on T-shirts.
 
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mfb said:
Took a minute to filter out all the plant hits: https://www.math.ias.edu/csdm/files/Archives/11-12/nalon_on_sunflowers_and_matrix_multiplication.pdf (PDF)

Doesn't that take the cake for blasé? Where does that come from? Oh, just some universe.
 
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Today I learned that the nym of our outstanding molecular biology contributor, Yggdrasill, does not stand as I thought for an amino acid sequence of occurrence and function unknown to the rest of us, but is the name of the Great Tree from which the Norse believed themselves descended.

Tree of life theme of course appropriate for a molecular biologist.
 
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  • #3,353
Today I learned that there is a National Procrastination Week. It should take place the first week in March, but it can be up to a week late.

(Actually I learned this yesterday, but ...)
 
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  • #3,354
Today is National (US) Dog Day!

Every dog has its day.

Enjoy your dog!
 
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Oh, thank goodness! I thought this day would never come!
1598460899515.jpeg
 
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  • #3,356
TIL that the Mayday call came from m'aider.
 
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  • #3,357
fresh_42 said:
TIL that the Mayday call came from m'aider.
"M'aidez" - You(plural/respectful) help me
 
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hmmm27 said:
"m'aidez" - you (plural, respectful) help me
Nope, m'aider as short for (venez) m'aider.
 
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fresh_42 said:
Nope, m'aider as short for (venez) m'aider.

Owing to the difficulty of distinguishing the letter "S" by telephone, the international distress signal "S.O.S." will give place to the words "May-day", the phonetic equivalent of "M'aidez", the French for "Help me."
—"New Air Distress Signal," The Times [London], 2 Feb. 1923​
 
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https://science.howstuffworks.com/transport/flight/modern/mayday.htm said:
Frederick Stanley Mockford, a senior radio officer in London, was put in charge of finding an appropriate code word. He reasoned that because so much of the air traffic flew between Croydon and Le Bourget Airport in Paris, it might make sense to use a derivative of a French word.

He came up with "mayday," the French pronunciation of "m'aider" ("help me"), which itself is a distilled version of "venez m'aider," or "come help me." The U.S. formally adopted "mayday" as a distress signal in 1927.

https://www.merriam-webster.com/words-at-play/mayday-meaning-origin said:
The call spread well beyond the Channel; the new distress signal's use was reported as far away as Singapore. In 1927, the United States formally adopted it as an official radiotelegraph distress signal, helpfully explaining in Article 19 of their resolution that mayday corresponds "to the French pronunciation of the expression m'aider." (https://www.merriam-webster.com/ since 1828)
 
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