Today I Learned

[DrGreg]

Today I learned that the Mercator projection isn't what I thought it was.

When I was a child and teenager, I was told that the Mercator projection was what you got by putting a light source at the centre of a hollow transparent globe, and wrapped a piece of paper around the equator to form a cylinder. The pattern from the globe's surface projected onto the paper was the Mercator projection. That's what several pop-sci sources said, and (if my memory is correct) what teachers at school said, too.

Today I learned that was a lie. The projection described above is actually the central cylindrical projection. It's very similar to the Mercator projection near the equator but progressively differs as you move towards the poles. The true Mercator projection is a conformal mapping, which means that it preserves angles and, locally, the north-south and east-west scales are the same as each other. And that's why, historically, ship navigators liked it, because compass bearings at sea match angles on the map. (I say "historically" because I guess nowadays not many navigators use sextants and paper maps, but use GPS and computers instead.)

Lots of images comparing the two projections at: https://map-projections.net/compare.php?p1=central-cylindric&p2=mercator-84&w=1&sm=1&d=1

 

[Orodruin]

TIL that a lemon is a hybrid:

And even the bitter orange is one:


This means life never gave us lemons ... we made them. So making lemonade is a solution to a problem we created ourselves!

This just turned an optimistic proverb into a very pessimistic one.

TIL that the word citron, which is the Swedish word for lemon, exists in English but refers to what we in Swedish call a true lemon.

 

[berkeman]

TIL that the word citron, which is the Swedish word for lemon, exists in English but refers to what we in Swedish call a true lemon.

Wait, what?

https://www.gq-magazine.co.uk/cars/article/citroen-ds

 

[BillTre]

TIL that a lemon is a hybrid:

Since it seems that the hybridisicity of the lemon was determined by genome studies not historical breeding records, it may have been a natural hybrid (they do occur). Both the natural hybrid and one from a human breeding scheme would have similar genomes.
Maybe the citron is different.

 

[DrGreg]

TIL that the word citron ... refers to what we in Swedish call a true lemon.

https://www.gq-magazine.co.uk/cars/article/citroen-ds

I thought it was the Citroën 2CV that many said was a true lemon?

 

[Ibix]

I thought it was the Citroën 2CV that many said was a true lemon?

There was a guy who lived near where I grew up who had a 2CV with a spoiler on the back.

 

[BillTre]

 

[Hornbein]

Today I learned that the Mercator projection isn't what I thought it was.

When I was a child and teenager, I was told that the Mercator projection was what you got by putting a light source at the centre of a hollow transparent globe, and wrapped a piece of paper around the equator to form a cylinder. The pattern from the globe's surface projected onto the paper was the Mercator projection. That's what several pop-sci sources said, and (if my memory is correct) what teachers at school said, too.

Today I learned that was a lie. The projection described above is actually the central cylindrical projection. It's very similar to the Mercator projection near the equator but progressively differs as you move towards the poles. The true Mercator projection is a conformal mapping, which means that it preserves angles and, locally, the north-south and east-west scales are the same as each other. And that's why, historically, ship navigators liked it, because compass bearings at sea match angles on the map. (I say "historically" because I guess nowadays not many navigators use sextants and paper maps, but use GPS and computers instead.)

Lots of images comparing the two projections at: https://map-projections.net/compare.php?p1=central-cylindric&p2=mercator-84&w=1&sm=1&d=1

John Dee was in his days the most educated man in England. He went to Europe to catch up with the technology. Back to England he brought Euclid's Elements and the Mercator projection. This was crucial for navigation. John more or less founded the British Navy and the general concept of benevolent Empire.

It was widely believed that his mastery of witchcraft caused the sinking of the Spanish Armada. His home was sacked owing to his alleged diabolism.

I'm doing this from memory so don't entirely trust it.

 

[fresh_42]

TIL that Newton was forced into the home office due to a lockdown because of the plague.

Interesting perspective. And before you complain or oppose, this is exactly how the anthropological principle works: causality a posteriori.

 

[Hornbein]

Today I learned of the existence of the Westinghouse Five Million Volt Atom Smasher, a van der Graff generator in Pittsburg, PA. https://en.wikipedia.org/wiki/Westinghouse_Atom_Smasher#https://en.wikipedia.org/wiki/Westinghouse_Atom_Smasher#

 

[Astronuc]

TIL, Anglo American owns 85% of De Beers Group, the world's leading diamond company. The remaining 15% is owned by the Government of the Republic of Botswana (GRB). De Beers Group and its partners produce around one third of the world's rough diamonds, by value.
https://www.angloamerican.com/products/diamonds?product=diamonds

I did not know that.

BHP Group (the world's largest mining company by market capitlaization) has been attempting a merger/acquisition of Anglo American. Anglo American, which produces diamonds (De Beers), platinum, nickel, iron ore and manganese, metallurgical and thermal coal, and copper, would have to spin off their South African iron ore and platinum businesses.
https://www.angloamerican.com/about-us/where-we-operate
https://finance.yahoo.com/news/bhp-investors-see-anglo-american-060409225.html

Glencore (a Swiss-based commodities trading and mining company) may be the largest based on revenue.

 

[BillTre]

 

[DrGreg]

Today I learned that if you ask Google Maps to measure a long distance, it correctly displays the geodesic as appearing to be curved on the chart.

 

[fresh_42]

Today I learned that if you ask Google Maps to measure a long distance, it correctly displays the geodesic as appearing to be curved on the chart.

View attachment 346462

And I thought my preferred tool would have had the driving distance in addition to the geodesic, but no, no driving routes across oceans.

Now I know something that no American knows! The distance (SD - NYC, air and land) in kilometers!

 

[pinball1970]

TIL Hubble is reducing its observations due to gyroscope failures.
https://phys.org/news/2024-06-hubble-veteran-space-telescope-easy.html

 

[Hornbein]

The word ‘orange’ is relatively new to the English language and first appeared in 1502 in reference to clothing belonging to Margaret Tudor, the Scottish Queen. The orange, native to China, arrived in Europe with the Arabs at the beginning of the eighth century and was called the sinaasappel (Chinese apple) in Dutch.

https://www.counterpunch.org/2024/06/05/the-humble-carrots-colorful-history/

 

[Orodruin]

The word ‘orange’ is relatively new to the English language and first appeared in 1502 in reference to clothing belonging to Margaret Tudor, the Scottish Queen. The orange, native to China, arrived in Europe with the Arabs at the beginning of the eighth century and was called the sinaasappel (Chinese apple) in Dutch.

https://www.counterpunch.org/2024/06/05/the-humble-carrots-colorful-history/

Still called similarly in different languages. Apelsin in Swedish for example.

 

[collinsmark]

The word ‘orange’ is relatively new to the English language [...]

It is an unusual word. I mean, just try to think of a word that rhymes with "orange."

I don't think there are any words (spoken in English; proper nouns not allowed) that rhyme with orange. Okay, maybe "sporange," which is a technical jargon word (I had to google for that).

 

[Hornbein]

I've long been amazed by this. Isn't orange one of the seven bands in the rainbow? Did they actually count six? Maybe they had more important things to do, like staying alive.

The Pleiades hold a similar mystery. In the legends there are usually seven Pleiades but we see only six. ?

 

[BillTre]

TIL its national zoo and aquarium month.

When I was four years old, lived across the road from the National Zoo in DC for a year.
It became my main playground.

 

[docnet]

TIL its national zoo and aquarium month.

When I was four years old, lived across the road from the National Zoo in DC for a year.
It became my main playground.

so lucky! Did that experience made you want to get your neurodevelopmental biology degree?

 

[BillTre]

so lucky! Did that experience made you want to get your neurodevelopmental biology degree?

I am guessing it had something to do with that.
Its a good story anyway.

Its also why I like gibbons so much.

 

[BillTre]

 

[Hornbein]

Today I learned that Wikipedia says Justin Bieber has Albrecht Durer's Praying Hands tattooed on his left leg.

 

[jack action]

TIL about the Allis-Chalmers fuel-cell tractor, developed in the 1950's:

​

 

[BillTre]

Don't underestimate the smarts of normal people:

 

[BillTre]

 

[BillTre]

 

[pinball1970]

USA beat Pakistan in the Cricket 20 20, amazing result.

Some highlights here, the catch at 15 seconds in, wow.



Looks like a lot of money being thrown at it too. Americans and cricket.....never saw that one coming!

 

[Hornbein]

USA beat Pakistan in the Cricket 20 20, amazing result.

Some highlights here, the catch at 15 seconds in, wow.



Looks like a lot of money being thrown at it too. Americans and cricket.....never saw that one coming!

I live in Indonesia. It's the fourth most populous country in the world but they never beat anyone in football/soccer. They just don't see the point. However when they got second in the world in badminton that was front page news. Badminton is a big deal in Indonesia because it doesn't take up much space. Java is very densely populated, they have little space, so badminton is IT. China was first but beating China is hopeless so that didn't dampen anyone's joy.

Today I learned that the world singles badminton champion is Danish. Hail individualism! Denmark has long been the European numba one in badminton.

 

[pinball1970]

T.I.L. William Anders killed in a plane crash.

https://en.wikipedia.org/wiki/William_Anders

“In December 1968, Anders flew on the Apollo 8 mission, the first mission where humans traveled beyond low Earth orbit,[9] and the first crewed flight to reach and orbit the Moon.[21] When the spacecraft came out from behind the Moon for its fourth pass across the front, the crew witnessed an "Earthrise" for the first time in human history.[22]”

 

[DaveC426913]

It is an unusual word. I mean, just try to think of a word that rhymes with "orange."

door hinge
syringe
lozenge
scavenge

Technically, one syllable words are rhymes too, so fringe, grundge, lunge.

Now if you want a word that's hard to rhyme with, try month. (I was only able to manage it by affecting a lithp and putting it in a dirty limerick).

I've long been amazed by this. Isn't orange one of the seven bands in the rainbow? Did they actually count six?

Don't know how much truth there is to it, but I heard that Newton had a thing for 7, so he inserted Indigo as one of the colours of the rainbow.

 

[fresh_42]

Don't know how much truth there is to it, but I heard that Newton had a thing for 7, so he inserted Indigo as one of the colours of the rainbow.

He had a rather dark side:

Isaac Newton's belief in spirits and alchemy may have been essential to achieving his towering scientific achievement: gravity. A new science and arts festival begins this weekend to explore this complex man

https://www.theguardian.com/science/across-the-universe/2012/sep/21/isaac-newton-scientist-sorcerer

 

[Orodruin]

door hinge

 

[Hornbein]

Today I learned that

[Hobson's choice] is often used to describe an illusion that multiple choices are available. The best known Hobson's choice is "I'll give you a choice: take it or leave it", wherein "leaving it" is strongly undesirable.

The phrase is said to have originated with Thomas Hobson (1544–1631), a livery stable owner in Cambridge, England, who offered customers the choice of either taking the horse in his stall nearest to the door or taking none at all.

Previously I had thought it was a choice between two equally undesirable alternatives. Some say that's dilemma, but others (such as I) say the requirement is less, that the alternatives be equal. A dilemma could be a choice between two equally craveable mates.

OK, if you believe in the "undesirable" option, then what do you call a choice between two highly desirable yet mutually exclusive alternatives?

 

[BillTre]

Got an ad from a local toy store saying that tomorrow is international Day of Play.
Enjoy!

 

[Klystron]

OK, if you believe in the "undesirable" option, then what do you call a choice between two highly desirable yet mutually exclusive alternatives?

Need to work on an expression for two desirable outcomes but can offer updates to the old-timey Hobson's Choice argument. Around mid 20th C., technical engineering descisions and standard practices largely replace the idea of "choice", as in choosing a reliable horse.

Various expressions of Murphy's Law, Finagle's Constant and logical pessimism offer little hope for competing optimismistic outcomes:

"If it can go wrong, it will go wrong".
"The perversity of the universe tends toward a maximum.

Murphy's law[a] is an adage or epigram that is typically stated as: "Anything that can go wrong will go wrong." In some formulations:

AKA Finagle's Corollary to Murphy's Law

it is extended to "Anything that can go wrong will go wrong, and at the worst possible time."

Philosphers point out contradictions in these adages but test pilots who worked with Murphy found wisdom. Yet another form: "Assume the worst. You will seldom be disappointed."

 

[Hornbein]

Need to work on an expression for two desirable outcomes but can offer updates to the old-timey Hobson's Choice argument. Around mid 20th C., technical engineering descisions and standard practices largely replace the idea of "choice", as in choosing a reliable horse.

Various expressions of Murphy's Law, Finagle's Constant and logical pessimism offer little hope for competing optimismistic outcomes:

"If it can go wrong, it will go wrong".
"The perversity of the universe tends toward a maximum.


AKA Finagle's Corollary to Murphy's Law


Philosphers point out contradictions in these adages but test pilots who worked with Murphy found wisdom. Yet another form: "Assume the worst. You will seldom be disappointed."

I was an engineer and can attest to the correctness of such pessimism. Thank God the outside world isn't like that.

 

[bhobba]

USA beat Pakistan in the Cricket 20 20, amazing result.

At the turn of the last century, believe it or not, cricket was quite popular in the USA; so much so it was reported equally with baseball in the press.

In Australia, before cricketers got paid a fortune for playing IPL etc, in the off-season they played a lot of baseball. Ian Chappell played for his local baseball club near his home.

Both baseball and cricket are played in the USA and Australia, it just for various reasons in each country, one has become more popular than the other.

 

[Hornbein]

@oliviervancantfort5327​

1 year ago
Never underestimate the power of herd behaviour. I had an amazing example some years ago (before we all got Waze in our pocket). I was like many other people driving home from holidays. The traffic on the highway was very dense but still fluid. Then there was a police car next to the largest mobile electronic sign that I ever saw outside concerts. It read "Warning ! Work ahead - 1 lane only. Currently : 20 km jam, 4 hours delay!Alternative: take next exit and follow signs. 15 min delay". So I left the overcrowded highway and followed the signs. To my utter amazement,I was totally alone. I saw no car in front of me or in my mirror for about 15 minutes. Talk about ignoring your personal information to follow the herd .

Herd behaviour is exacerbated in stress and disaster situations. I had emergency training with firemen for my work and one of the first thing they taught was that, if you are ever caught in a disaster, ignore the crowd, stop 30 seconds to observe and think by yourself. They had numerous examples of crowds passing right in front of emergency exits and ignoring them, or worse, running towards the danger...

 

[fresh_42]

I just see on TV a documentary about LNG from the US. They said that people don't want to see burning flames, so they release the methane directly into the air.

 

[phinds]

I just see on TV a documentary about LNG from the US. They said that people don't want to see burning flames, so they release the methane directly into the air.

Hey, don't be making fun of my farts !

 

[fresh_42]

Hey, don't be making fun of my farts !

Well, I am not allowed to comment on what I really think here. It is allowed to call German politics poor, but it is not allowed to say the same thing about American politics, sorry.

 

[Hornbein]

I just see on TV a documentary about LNG from the US. They said that people don't want to see burning flames, so they release the methane directly into the air.

I don't understand. There's a fire so they release methane?

 

[Hornbein]

Well, I am not allowed to comment on what I really think here. It is allowed to call German politics poor, but it is not allowed to say the same thing about American politics, sorry.

But aren't you also forbidden to say that you're not allowed to say what you believe? I suppose we shall see, eh?

 

[fresh_42]

I don't understand. There's a fire so they release methane?

They release the byproduct of methane of LNG pumps into the air. A flame would provoke questions, but methane is invisible so there is no need to draw any attention.

Proof here:
https://www.physicsforums.com/threads/today-i-learned.783257/page-171#post-7096917

 

[Hornbein]

They release the byproduct of methane of LNG pumps into the air. A flame would provoke questions, but methane is invisible so there is no need to draw any attention.

Aha. Well then today I too have learned something.

 

[fresh_42]

But aren't you also forbidden to say that you're not allowed to say what you believe? I suppose we shall see, eh?

<self censored>
Quod licet iovi (Americans) non licet bovi (non Americans).

 

[Hornbein]

They release the byproduct of methane of LNG pumps into the air. A flame would provoke questions, but methane is invisible so there is no need to draw any attention.

As Billy Crystal was wont to say, "it is better to look good than to feel good, don't you agree?"

 

[fresh_42]

As Billy Crystal was wont to say, "it is better to look good than to feel good, don't you agree?"

I like a quotation from an American novelist. I have forgotten his name, but he said: "We are the first generation that won't save itself because it's not profitable."